Additive Technologies

Holders: Prof. Govekar Edvard, Assoc. Prof. Klobčar Damjan

SUBJECT DESCRIPTION

Short description:

The subject covers the field of additive manufacturing (AM) with emphasis on AM of metals. By lectures, tutorials and hands-on work in the lab students acquire the knowledge and skills required to perform the whole AM production chain including product design process selection, , manufacturing process and its control, as well as post processing. In-depth knowledge of metal AM manufacturing is enriched by practical lab work on different AM processes including wire-arc, selective laser melting and direct laser metal deposition AM systems.

Prerequisites:

•  Physics (radiation, wave, electron beam, laser, heat conduction, advection and convection, plasma, ultrasound, x-ray),
•  Materials (properties of metals)
•  Laser systems (laser sources, laser light absorption, laser beam parameters, optical elements such as fiber leads, collimator, focusing optics)
• Manufacturing technologies 1 and 2 (characteristics of joining processes and material removal processes )

Content (Syllabus outline):

• Introduction and basic concepts of additive manufacturing technologies (AM):
• Basic physical principles of AM of metals
• Product design specifics for AM
• Use of multiple materials in AM
• Overview of AM systems and processes for metals
• Direct arc deposition of metals (WAAM)
• Laser AM of metals – systems and processes
• Selective laser melting processes
• Direct laser deposition of metal powder and wire
• Post processing and providing functional characteristics
• AM process selection guidelines
• Software in the field of AM
• Functional products manufacturing examples

Objectives and competences:

Objectives:

• Learning the possibilities and potentials of additive manufacturing technologies
• Learning the elements of the entire production chain from product model, AM simulations to the final functional product
• Learning the systems and processes of AM of metals
• Identifying cost-effective technology and business opportunities for successful implementation to achieve added value.

Competences:

• Ability to identify and select appropriate AM technology for the product according to the product functional requirements.
• Ability to master the entire process chain, including AM, to produce the final functional product.
• Ability to analyse and determine the impact of basic process parameters of AM on product properties.

Intended learning outcomes:

In-depth theoretical, methodological and analytical knowledge with elements of research in the field of additive manufacturing technologies, covering product modeling, material knowledge, AM and subsequent processing technologies with the aim of producing complex functional products.

Mastering highly demanding, complex workflows and methodological tools in a specialized broader field of additive manufacturing technologies. Preparation and implementation of elementary experiments to analyse the effects of process parameters on the properties of products manufactured with AM.

Forms of assessment:

Written examination (obligatory), Oral examination (optional), Seminar work (obligatory)

Micromanufacturing Technologies

Holders: Assoc. Prof. Valentinčič Joško

SUBJECT DESCRIPTION

Short description:

Lectures and tutorials cover micromanufacturing technologies for manufacturing single product as well as bath and mass production. Lab work is an important part of the course, where students get hands-on experience on some of the technologies.

Prerequisites:

Finished batcher study

Content (Syllabus outline):

1. Microfabrication and micromanufacturing
2. Lithography and lithography-based processes
3. Micro electrochemical machining
4. Micro electrical discharge machining
5. Laser ablation
6. Mechanical micromachining
7. Stereolithography
8. Micro injection moulding
9. Process chains
10. Microreactor systems

Objectives and competences:

In scope of the Micromanufacturing technologies courses, the students will:

1. get familiar with micromanufacturing technologies in terms of physical processes and their technological capabilities,
2. understand the use/role of microtechnologies in modern production processes,
3. apply the knowledge from the literature to practice,
4. identify appropriate technologies and/or process chains for micro product manufacturing,
5. build numerical models and perform simulations of some micromanufacturing processes.

The students will earn the following subject-specific competences:

1. master micro-manufacturing technologies and applications,
2. ability to find technological solutions for micro-product manufacturing,
3. ability to search for sources of information, critical judgment and practical application,
4. ability to design products that can be effectively fabricated with micromanufacturing technologies,
5. ability to perform simulations of some micromanufacturing processes and use of microcomponents.

Intended learning outcomes:

1. Thorough theoretical, methodological and analytical knowledge with elements of a research work that form a basis for very demanding professional work.
2. Master very demanding and complex work processes and methodological tools in specialised professional fields.

Gain ability of unique innovations and critical reflections.

Assembly and Handling Systems

Holders: Prof. Herakovič Niko, Assist. Prof. Šimic Marko

SUBJECT DESCRIPTION

Prerequisites:

The condition for admission to exam is a passing grade for exercises and other individual assignments.

Content (Syllabus outline):

• The overview and role of assembly and handling systems (AaHS) in the production process.
• The argumentation and conditions for the automation of AaHS, basic concepts and the strategy for AaHS automation.
• Economical aspects of AaHS automation.
• The concepts of rigidly and flexibly automated AaHS.
• Analysing the cases of assembly and handling process automation.
• Robotic assembly and handling systems.
• The structure of industrial robots (IR): degrees of freedom, typical IR, components, workspace (dextrous and reachable), drives, sensors,
• IR geometry: coordinate systems, geometry of the tip, links, joints and grippers.
• The basics of kinematic modeling: kinematics of IR, relations between velocities and accelerations, generating working motion, defining tasks, profiles, interpolations.
• IR control and safety. Human-robot collaboration. Programming IR: online and offline programming.
• External sensors in robotic AaHS, tactile sensors and robot vision.
• Grippers, manipulation grippers and technological tools, gripper sensors.
• Standards and safety in robotic AaHS.

Objectives and competences:

Goals:

• To teach the students the fundamentals of methodology used in the selection, design, analysis and evaluation of automated assembly and handling systems (AaHS), and about the integration thereof into the production process.
• Acquisition of basic knowledge for planning and integration of robotic AaHS into the production process.

Competences:

• The ability to select, design, analyse and evaluate automated and robotic AaHS, as well as the integration thereof into the production process.
• Understanding the economic aspects of automation and robotization of AaHS.
• Knowing the significance of standards and safety in robotic AaHS

Intended learning outcomes:

Knowledge and understanding

The student learns and understands:

• The fundamentals of automated assembly and handling systems, rules and models.
• The fundamentals of robotics, the structures, relations, robotic applications in automated AaHS.
• The fundamentals of gripper technology in automated AaHS and the fundamentals of robotic grippers.
• The significance of standards and safety in robotic AaHS.

Usage

The students use the knowledge attained for planning and analysing AaHS, as well as for the integration thereof into the production process.

Reflection

Using the presented methodologies and technologies in solving real problems.
Transferrable skills – related to more than one course
Using domestic and foreign literature.
Problem identification and methods of problem solving.
The ability to plan and manage projects focused on designing assembly and handling systems.

Advanced Machining Processes

Holders: Prof. Pušavec Franci

SUBJECT DESCRIPTION

The scope of the course »Advanced machining processes« is to provide a broad knowledge on machining processes (conventional and novel processes), with covering thematic from machining kinematics, loads, cutting tool geometries and principles for optimization of machining process. The subject will consist of lectures addressing following topics (theoretical and practical): Basic tool kinematics and chip formation, Defined cutting geometry, Chip formation models, Determination of machining efficiency, Cutting forces, Nondefined cutting geometry, Thermal loads in machining, Tool-wear and tool-life, Cutting tools, Cooling and lubrication of machining processes, Productivity and economy, Optimization of machining processes, Special/modern machining processes, and Guest lecture by an expert from industry on machining technologies in industrial applications.

Heat Treatment

Holders: Assist. Prof. Kek Tomaž, Prof. Šturm Roman

SUBJECT DESCRIPTION

Course objectives:
The objective of the Heat treatment course is to provide the students with the necessary fundamentals for understanding the material properties given by the available heat treatment processes. A special presentation is delivered of phenomena occurring in the materials and influencing the achieved properties of core and surface of treated material.

Course enrolment requirements:
Completed first level studies in mechanical engineering or natural sciences or other fields with knowledge of fundamentals in the field of material science.

Objectives and competences:
Students gain knowledge about the materials used in mechanical engineering, the physical properties and the microstructural phenomena characteristic to the individual material groups, with respect to the different heat treatment processes.

Intended course learning outcomes:
The ability to assess the behaviour of materials from the viewpoint of the selected heat treatment. A good knowing of surface integrity yielded by different heat treatment processes. The ability to evaluate the microstructural transformations in the material after different thermal and thermochemical treatments. The ability to evaluate and select an optimal heat treatment or surface hardening.

Laser Measurement Systems

Holders: Assoc. Prof. Jezeršek Matija

SUBJECT DESCRIPTION

Short description:

Lectures and tutorials cover laser systems for measuring distances, speeds, 3d surface shapes at micro and macro levels and 3d deformations. Lab work is an important part of the course, where the content of the lectures is tested and upgraded so that students create measurement systems, perform test measurements with them, and process and interpret the data appropriately.

Prerequisites:

The following pre-knowledge is recommended for successful study:

• Physics (geometry optics, wave optics)
• Basic principles of lasers
• Mechatronics
• Computer programming

Content (Syllabus outline):

1. Building blocks of laser measurement systems
2. Interferometry
3. Laser triangulation technique for 3d scanning
4. Calibration techniques
5. 3d measurement using Time-of-flight principle
6. Post-processing of measured data

Objectives and competences:

In scope of the Laser measurement systems course, the students will:

• become aware of the significance of measurement technology,
• earn the ability to select suitable measurement systems in the working process,
• develop a perception about the continuous improvement of manufacturing and diagnostic processes.

The students will earn the following subject-specific competences:

• knowing the fundamental principles of laser measurement technology,
• knowing the characteristics, advantages and limitations of individual laser measurement methods,
• knowing the applications of laser measurement systems,
• practical knowledge in the field of development of laser measurement systems.

Intended learning outcomes:

Knowledge and understanding

The students will:

• understand the basic physical laws in the field of laser measurement technology;
• understand the operation of different laser measurement methods, their characteristics, structure and applications;
• know the basic operations in digital image processing;
• know the state-of-the-art in the field of laser measurement systems;
• know the procedures used for planning and developing the individual laser measurement methods.

Manufacturing Automation

Holders: Assist. Prof. Bračun Drago

SUBJECT DESCRIPTION

Prerequisites: English language, basic understanding of physics, mechanics and electrictricity.

Content (Syllabus outline):

• Introduction: motivation: efficiency, variability; types of automation (fixed, flexible, programmable), automation migration strategy. Basic building blocks: sensors, actuators, controllers, industrial data communications, user interfaces.
• Robotic systems: robot specification, integration, end effectors, external sensors, typical applications.
• Numerically controlled systems, structure, characteristics, and calculation of NC drive.
• Automation of material flow, basics, rails, belts, AGV systems.
• Localization, review of contact and contactless methods, localization for CNC systems, localization of objects with random poses.
• Systems for monitoring and control of production systems, SCADA, MES, monitoring systems, industrial internet of things. Automatic identification and data capture: overview, bar and QR code, RFID.
• Process and product control: variability, 100% vs. sampling control, process management and control. Automated inspection devices: contact inspection methods, contactless inspection methods. -Imaging systems in automation: illumination and light effects, camera and lens selection, image sampling and aliasing. Specifics of image processing at dimensional part inspection, detection of surface defects, part localization, seam tracking. Imaging systems calibration: camera model, calibration and image correction, calculation of 3D space coordinates. Example applications of imaging systems in automation: dimension inspection, surface defect detection, seam tracking.
• Performance of automation systems.

Goals:

• Understand the use of automation to improve productivity and reduce variability in production.
• Understand the integration of basic mechatronic components in automated systems.
• Understand the basic methods of localization and product identification.
• Understand the synthesis of measuring and mechatronic systems in automated control devices.
• Understand the use of machine vision in product automation and inspection.
• Understand the definition of performance and security of automated systems.

Competences:
The use of avtomation to improve productivity and reduce variability in production.
Integration of mechatronic components in automated systems.
Understanding the basic methods of localization and product identification.
Development of inspection devices.
Use of machine vision.
Ability to analyse performance and security in automated systems.

Learning and teaching methods:
Lectures: Auditorium lectures using modern and well-established audio-visual techniques.
Participation of experts from the industry and internationally established researchers.
Exercises: laboratory exercises. Practical work in scope of the seminar.

Advanced Sensory Systems and Networks

Holders: Prof. Podržaj Primož

SUBJECT DESCRIPTION

1. Lecture: The basics of digital image processing
   • Image as a matrix
   • Image representation in a computer
   • Color, black and white image
   • Color spaces and transformations between them
2. Lecture: Point processing
   • Linear and nonlinear operations
   • Histogram
3.  Lecture: Neighbourhood processing
   • Correlation
   • Edge detection
   • Image sharpening
4. Lecture: Advanced algorithms
   • Dilation, erosion
   • BLOB analysis
5. Lecture: Machine vision
   • Segmentation
   • Features
   • Tracking
6. Lecture: Application of Python for machine vision
   • Overview of the most important libraries
   • Applications
7. Lecture: Nonconventional sensors
   • MEMS
   • Microsensors
   • Smart sensors and smart sensory systems
8. Lecture: Fuzzy logic
   • The basics of fuzzy sets
   • Soft inference
   • Fuzzy logic-based control
9. Lecture: Neural networks
   • The basic types of neural networks
   • Neural network learning
   • Application of neural networks
10. Lecture: Sensor fusion
    • Types of fusion
    • Applications
    • Practical approaches
11. Lecture: Internet
    • Functioning
    • DNS
    • Distance vector routing
    • Link-state routing
12. Lecture: Internet programming
    • Node.js environment, JavaScript programming language
13. Lecture: Servers
    • Server setup
    • Reading from and writing on a server
14. Lecture: Security
    • Encryption
    • Attacks on the server side
    • Attacks on the client side
    • SQL injection
    • Cross-site scripting
15. Lecture: Programming of IoT applications
    • Sensor part (remote acquisition)
    • Actuator part (remote control)
    • Development of IoT control application on the selected platform

Readings

• 1. Thomas B. Moeslund: Introduction to Video and Image Processing, Springer, 2012
• 2. Ali Zilouchian: Intelligent Control Systems Using Soft Computing Methodologies, CRC Press, 2001
• 3. Deep Medhi: Network Routing: Algorithms, Protocols, and Architectures, Morgan Kaufmann, 2018

Laser Processing Technology

Holders: Assoc. Prof. Gregorčič Peter, Assoc. Prof. Jezeršek Matija

SUBJECT DESCRIPTION

Short description:

The mechanisms of interaction between laser light and material are introduced in the first part. Particular emphasis is given to the effects on the absorption of light in material and the conversion of light energy into heating and subsequent melting, evaporation and ionization. The second part introduces the technologies of laser drilling, cutting, welding, marking, 3D printing and microstructuring of surfaces. Furthermore, laser control systems based on optical and optodynamic principles are presented. Tutorials consist of calculus cases and laboratory research topics, where small groups work on specific research topics in the field of laser processing through a semester, thus consolidating knowledge from lectures and gaining practical skills.

Prerequisites:

The following pre-knowledge is recommended for successful study:

• Physics
• Laser systems
• Mechatronics
• Materials

Content (Syllabus outline):

1. Optodynamics and interaction of laser light with matter
2. Laser cutting and drilling
3. Laser welding
4. Modeling of laser processes
5. Laser etching and marking
6. Laser surface engineering
7. 3D print
8. Monitoring and control of laser processes

Objectives and competences:

In scope of the course, the students will:

• become aware of the significance of laser processing technology,
• earn the ability to select suitable laser processing systems in the working process,
• develop a perception about the continuous improvement of manufacturing and diagnostic processes.

The students will earn the following subject-specific competences:

• knowing the fundamental principles of laser processing technology,
• knowing the characteristics, advantages and limitations of individual laser processing technology,
• knowing the applications of laser processing,
• practical knowledge in the field of development of laser processing systems.

Intended learning outcomes:

Knowledge and understanding

The students will:

• understand the basic physical laws in the field of laser processing technology;
• understand the operation of different laser processing systems, their characteristics, structure and applications;
• know the state-of-the-art in the field of laser processing systems;
• know the procedures used for planning and developing the laser processing systems.

Robotic Systems

Holders: Assist. Prof. Vrabič Rok

SUBJECT DESCRIPTION

Robotic systems is an introductory course that covers the fundamentals of robotics, industrial and mobile robots, and design of robotic systems. Both articulate robots (robot arms) as well as mobile robots (autonomous guided vehicles) are considered. The acquired competences include the abilities to develop custom robotic applications, to integrate robots with other industrial systems, and to develop robotic software and hardware components. The course addresses robotic sensors, actuators, and controllers, as well as robotic system planning and implementation.

The main prerequisites are basic knowledge of linear algebra, kinematics and dynamics, basics of probability and statistics, programming, and numerical methods. The prerequisites are reviewed and detailed at the beginning of the course with the emphasis on their use in the domain of robotics. The course syllabus covers coordinate systems in robotics, direct and inverse kinematics, velocity kinematics, dynamics, path planning, control, and applications of industrial robots. Navigation, localisation, and industrial uses of mobile robots are reviewed.

Theoretical discussions are supported by practical tutorials with real and simulated robots, using open-source tools as well as proprietary tools from robot manufacturers for the development of robotic applications. The tutorials cover robot programming using teach pendants, robot modelling and simulation, mobile robot navigation, integration of robots with external systems, and development, validation, and testing of robotic systems for practical industrial applications.

Solar Utility Technologies

Holders: Prof. Medved Sašo

SUBJECT DESCRIPTION

Sun is the most important energy source for our planet and humanity. In the nature, solar energy is transformed into the heat, kinetic energy of the air mass, organic mater by plants and runs the water cycle. Due to the goals of global energy policy driven by global climate change, it is widely excepted that Sun will have major role in sustainable development and zero carbon societies. Technological development in last decades have led to the energy efficient, environmental friendly and cost efficient technologies for production of heat, cold and electricity, the most used energy carriers, by utilization of solar energy. These technologies will be presented in the course.

The course starts with introduction lecture in which overview of origin of the renewable energy sources (RES) is given, together with description of current status of RES technologies on the global and EU scale. EU policy in field of renewable energy sources, including relevant Directives is presented. Course continues with theoretical chapters, which are intended to describe theoretical models for determining solar energy potential, including models of extraterrestrial potential and impact of air mass. Theoretical background and models for determination of solar radiation and irradiation on fixed and tracking surfaces are presented.

Course continue with technology chapters. Each technology of the solar energy utilization is explained with physical principles of operation. Methods for modeling of conversion of solar energy into the particular energy carrier, design guidelines and assessment tools for energy efficiency and environment impacts are presented, supported by the number of best practice examples. Following technologies for production of the heat, cold and electricity are discussed;

• low temperature passive heating of the buildings, including the presentation of selective optical properties of sun radiation absorption surfaces and adaptive controlling of the transmission of sun rays through of the building envelope and methods for passive heating evaluation;
• active solar hearing systems including modeling and experimental evaluation of solar thermal collector’s efficiency, modeling of transient operation of short and long term heat storages, design and assessment of solar heating systems, including solar district supported systems;
• technologies for utilization of solar energy in agriculture including drying, desalination and solar chemistry;
• solar cooling with desiccant-evaporative and sorption cooling;
• solar thermal system for electricity production including solar towers, solar pounds and solar thermal power plants;
• photovoltaics, including stand alone and building integrated solutions and hybrid PV techniques.

Students will get theoretical and engineering knowledge to make a project seminar in which the design of solar utilization technologies and evaluation of the energy, environmental and cost performance based on life cycle and life cost principles will be shown.

Experimental Modelling in Energy and Process Engineering

Holders: Prof. Hočevar Marko

SUBJECT DESCRIPTION

Curriculum:

The subject deals with the experimental and modeling methods in energy and process engineering. We position the subject topics as a small subsection of the digital twin. In the introduction, students will learn the basics of turbine machinery and dimensional analysis.

In the part related to experimental work, measuring stations design is introduced for measurement of fans, pumps, and turbines characteristics. Major measuring station types are discussed. Measurement equipment and its installation are explained. This includes pressure, volume flow rate, torque, rotational frequency, electric current, voltage, power, etc. The operation of electric motors and generators operation is explained. Students learn how to design an experiment and pre-process the data before the modeling.

A section on modeling methods focuses on linear statistical models as grey or black boxes. Parametric and non-parametric models are compared. Properties of linear models are explained. Methods on how to determine model parameters and evaluate their quality will be discussed. The subject will finish with a few examples.

Study material is available in English.

Prerequisites:

Finished 1st cycle academic study program.

Turbomachinery

Holders: Prof. Hočevar Marko

SUBJECT DESCRIPTION

Prerequsites:

Finished 1st cycle academic study program.

Curriculum:

The subject deals with the operation of turbine machines, ie fans, compressors, pumps and turbines. The study material is divided into twelve chapters. The division of turbine machines is given in the first introductory chapter. The second chapter deals with the efficiency of turbine machines. In the third and fourth section, based on the control volume approach, we derive the energy equation for turbine machines. Euler equation and velocity triangles (fifth chapter) are given for radial and axial pumps and turbines. In this case, stagnation pressure and enthalpy are considered. Based on the Euler equation, the influence of the blade angles on characteristics is explained. The sixth chapter contains the application of the theory of similarity in the case of turbine machines, we consider the pressure, flow and power numbers and specific speed. Since the development and production of water turbines in Slovenia are important areas of mechanical engineering, chapter seven deals with Pelton, Francis, Kaplan and bulb water turbines. The eight chapter describes the elements of the flow tracts of water turbines such as dams, penstocks, trash racks, surge tanks, guide vanes, turbine blades, draft tube, lubrication systems, bearings, gates, flow fields, etc. The ninth chapter describes the process of manufacture of water turbines. Chapter ten deals with the operation of water turbines, characteristics, hill diagrams and operation in four quadrants. In the eleventh chapter we discuss cavitation in pumps and turbines. In last chapter we perform simple design procedure for blade angles of a water turbine in relation to net positive suction head requirements and reactivity.

Study material is available in English.

Air-conditioning, Heating, Refrigeration, Ventilation

Holders: Assoc. Prof. Stritih Uroš

SUBJECT DESCRIPTION

Short description:

The course on Air-conditioning, Heating, Refrigeration and Ventilation will introduce the student to the field of building service engineering and technology and provide them with knowledge and experience for solving problems in the relevant subfields.

Prerequisites:

Thermodynamics

Heat and Mass transfer

Content:

1. Physiological, thermodynamic and meteorological bases
2. Heat and mass transfer in buildings
3. Calculation of heat losses (winter transmission)
4. Sources and devices for heating buildings
5. Distribution and other heating equipment in buildings
6. Heat transfer devices in buildings
7. Ventilation of the premises
8. Calculation of heat gains (annual transmission)
9. Cooling installations in buildings
10. Air conditioning and elements of air conditioners
11. Preparation and distribution of air for air conditioning
12. Blowing air into the room
13. Regulation of internal heating, cooling and air conditioning systems
14. Energy use and reduction in systems
15. Demonstration of system operation in practice

Process Engineering

Holders: Prof. Golobič Iztok

SUBJECT DESCRIPTION

Short description:

The course on Process Engineering will introduce the student to the field of process engineering and technology and provide them with knowledge and experience for solving problems in the relevant subfields. Throughout the lectures, the students will get to know thermal separation processes, drying, freezing, crystallization and both gas and liquid separation using membrane technologies. The second part of the course will focus on highly relevant and novel technologies of carbon capture and storage, bioprocess technologies and micro- and nanoscale process systems with the goal of educating the students on sustainable development and technological implications of the transition towards a carbon-neutral economy.

Prerequisites:

Proficiency in the following fields is recommended for successful study:

• Thermodynamics of mixtures
• Transport phenomena

Content (Syllabus outline):

• Introduction to process engineering
• Introduction to thermal process engineering
• Evaporation and distillation
• Rectification
• Planning of rectification devices
• Absorption, adsorption, extraction, crystallization
• Drying
• Membrane technologies for separation of liquids
• Membrane technologies for water and wastewater treatment
• Membrane technologies for separation of gases
• Environmental process technologies for carbon capture and storage
• Bioprocess technologies and lyophilization
• Engineering and management of processes
• Micro- and nanoscale process systems
• Student presentation of process engineering seminar work

Objectives and competences:

In scope of the course, the students will:

• learn about the basics of process engineering,
• develop an understanding of the role of process engineering in environmental engineering and sustainable development,
• become familiar with the use of engineering tools for problem solving in the field of process engineering and consolidation of engineering research approach to problem solving.

Knowledge and understanding

The students will:

• obtain thorough theoretical, methodological and analytical knowledge with elements of a research work in the field of process engineering,
• master demanding and complex work processes and methodological tools in process engineering,
• learn to plan and manage work process based on creative problem solving in process engineering together with the ability for ability for unique innovations and critical reflection.

Advanced Dynamics

Holders: Prof. Boltežar Miha, Assoc. Prof. Čepon Gregor

SUBJECT DESCRIPTION

Subject description:

Lagrangian mechanics: statics and dynamics. Principle of Virtual Work, generalized coordinates, d’Alembert principle, Lagrangian equations of the 2nd order, Hamiltonian approach for conservative systems.

Vibrations of the SDOF systems: periodic excitation (Fourier series) and impulse excitation (convolution).

Vibrations of the MDOF systems: Free vibrations-eigen value problem, eigen-frequencies and eigen-vectors, modal transformation; the response in modal coordinates. Forced vibrations: undamped and damped response, response in modal coordinates.

Vibrations of continuous systems: lateral vibrations of string, torsional vibrations of shaft and flexural vibrations of beam – Euler Bernoulli theory. Natural frequencies and modal shapes. Boundary conditions.

Real industrial cases.

Design of Advanced Systems

Holders: Prof. Klemenc Jernej, Prof. Nagode Marko

SUBJECT DESCRIPTION

1. Lecture: Prerequisites for design of complex systems: Product hierarchy and value chain; Effectiveness as a cross-section of product, operating conditions and environment; Failure as a random event.
2. Lecture: Effectiveness and value of product: Reliability, maintainability and supportability as basis for product availability; Influential factors for the product’s value; Product’s attributes and life-cycle costs; R&D information and influence to costs; RMS development process as an upgrade of the conventional R&D process.
3. Lecture: Statistical analysis of complex systems (basics): Probability distribution of a time to failure; Hazard rate; Basics of the Weibull’s analysis.
4. Lecture: Assuring the functional performance of a complex system: Basic product structures and their influence to probability of service; Advanced product structures and their influence to probability of service; Complex systems and a function of the product’s structure.
5. Lecture: Failure modes and failure models for complex systems and their components: Single-mode failure model; Multi-mode failure models (competing-failures model, mixed-failures model).
6. Lecture: Design of advanced and complex systems: V-model for design of the complex-product; Definition of requirements for a technical system; Allocation of requirements to the lower hierarchical level of the product.
7. Lecture: Design of advanced and complex systems: Measurement, prediction and analysis of load states in exploitation; Load distribution among the building blocks of the complex system.
8. Lecture: Design of advanced and complex systems: Modularity of technical systems; Redundancy as a cost in-effective approach for assuring the functional performance of the complex system.
9. Lecture: Design of advanced and complex systems: Decision for in-house development and manufacturing of components; Decision for procurement of components and their outsourcing.
10. Lecture: Design of advanced and complex systems: Integration of basic elements into the components and sub-systems; Linkage between the product decomposition and integration phases; Validation of partial technical solutions; FMEA analysis.
11. Lecture: Design of advanced and complex systems: Validation of the complex product; FTA analysis; Digital twin as a tool for analysis of interactions between the system’s building blocks.
12. Lecture: Product maintainability as a prerequisite for its availability: Maintenance types and a time structure of a maintenance intervention; Influence of preventive maintenance to failure distribution of technical systems; Overhaul.
13. Lecture: Product maintainability as a prerequisite for its availability: Planning of maintenance intensity as a function of an expected hazard rate of the product’s components; Proactive preventive maintenance; Reactive maintenance; Spare-parts supply and logistic support.
14. Lecture: Case study of a R&D process for a complex high-series product – selected topics from a passenger-car development process.
15. Lecture: Case study of a R&D process for a complex low-series product – selected topics from a development of an injection-moulding tool.

Rheology of Polymers

Holders: Assist. Prof. Slemenik Perše Lidija

SUBJECT DESCRIPTION

Prerequisites:

Non-metallic materials (basics of polymers – thermal properties, mechanical properties, time-dependent properties of polymers and polymer composites); Strength of Materials and Fluid dynamics.

Content (Syllabus outline):

INTRODUCTION: Basic rheological parameters, Material functions in time and frequency domain, Basic flow regimes, Effect of molecular weight on mechanical and rheological properties

RHEOMETRY: Instruments for determination of rheological properties, Geometries of sensor systems, Methods for determination of rheological properties of melts and solids, Calculation of rheological parameters

YIELD STRESS: Engineering examples of polymers with yield stress, Equations for rheological behaviour of materials with yield stress, Determination and prediction of the behaviour of polymers with yields stress

VISCOELASTICITY: Creep and relaxation – relation between stress and strain, Energy absorption, Mechanical models for prediction of viscoelastic behaviour during creep and relaxation, Explanation of the general stress-strain state of viscoelastic materials using material functions; Linear and non-linear behaviour of materials, Practical meaning of linear theory of viscoelasticity, Determination of stress limit

TIME DEPEDENCY of MECHANICAL PROPERTIES: Relaxation time, Thixotropy, Physical aging, Mechanical spectra

EFFECT of TEMPERATURE on RHEOLOGICAL and MECHANICAL PROPERTIES of POLYMERS: Temperature tests, Determination of phase transitions with dynamic moduli, Degradation

RHEOLOGICAL MEASUREMENTS of POLYMER MATERIALS: Selection of the proper rheological method, Interpretation of the results of rheological measurements, Relation of rheological properties with the structure of polymer; Relation of the rheological properties of melt with process parameters of polymer processing, Influence of viscoelastic properties on the polymer product during processing (Dye swell effect, Weisenberg effect, melt fracture, yield stress, …), Influence of time dependent properties on the performance (mechanical properties) and life-time of polymer products (gears, seals, valves, …)

SPECIAL APPLICATIONS of RHEOLOGICAL PROPERTIES of POLYMERS in MECHANICAL ENGINEERING – examples

Discussion and summary

Objectives and competences:

Goals: The course objective is to acquaint the students with the rheological and time-dependent behaviour of polymer materials and their composites, and with the material functions describing their behaviour in the time and frequency domains.

Competences:

• understanding the rheological behaviour of liquid- and solid-like polymers and composites,
• understanding the time-dependent behaviour of polymers and composites,
• mastering the research methods, procedures and processes, development of ability to do critical and self-critical evaluations,
• the ability to use the knowledge in the practice,
• the development of communication skills, especially for communication in the international environment,
• cooperativeness, teamwork (in the international environment).

Intended learning outcomes:

Knowledge and understanding

The students attain the knowledge on the rheological behaviour of synthetic and bio-polymeric materials. They understand the specialties of rheological and time-dependent behaviour of polymer melts and solid polymeric structural materials and the advantages offered by these materials in science and engineering. They master the mathematical approaches used to describe the behaviour of time-dependent materials in the time and frequency domain, as well as the prediction of life of products made from these materials.

Usage

The knowledge assimilated in the course will benefit the students in all disciplines of engineering using polymeric materials and corresponding composites. This knowledge is of special importance to technologists and design engineers.

Reflection

The theoretical knowledge acquired in the course and the experience gained in experimental practicum executed in the laboratory environment and partially on real objects in the industrial environment can be transferred directly and used for various research, development and practical purposes in the field of design and processing technologies.

Transferrable skills – related to more than one course

Using the modern professional literature and practical work with modern laboratory, measuring and software equipment.

Lightweight Structures

Holders: Assoc. Prof. Jerman Boris

SUBJECT DESCRIPTION

The Lightweight Structures course deals with the principles of designing modern lightweight structures. Steel, aluminum alloy, and composite structures are covered. The theoretical background relevant to the design of lightweight metal structures, including essential material properties, is presented. Practical procedures for the design, dimensioning, and intuitive optimization of lightweight metal structures with thin-walled rectangular and circular cross sections are discussed in detail. Welded joints are also considered. A semi-probabilistic design procedure is presented, as well as the fundamentals of probabilistic design criteria and limit states. The fundamental aspects of selecting an appropriate type of lightweight composite structure and the use of the finite element method in the design and dimensioning of lightweight structures are also discussed.

FEM Structural Analysis

Holders: Assoc. Prof. Halilovič Miroslav, Assoc. Prof. Mole Nikolaj

SUBJECT DESCRIPTION

Prerequisites:

For the on-going work and understanding of the subject basic knowledge of the following courses is needed:

• Mechanics of solids
• Numerical Methods

Coursework, on-going work and passing the course: The course consists of lectures and tutorials. Lectures: a new topic is presented and discussed weekly. Tutorials: on-going work is expected. A short test (approximately 15 minutes) is taken weekly. All the practical/numerical basis that are required for the tests are given in advance in the form of video lectures. Passing the course: the final mark consists of the assessment of the theory and assessment of the practical part (tutorials). The assessment of the theory is performed by written examination. A set of possible questions for the theory is given by the professor at the end of each lecture. The assessment of tutorials is obtained from short tests that are taken weekly on tutorials.

Acquired knowledge:

The course is intended for all students who want to acquire theoretical and practical knowledge on using numerical methods in solving mechanical problems, with emphasis on the Finite Element Method (FEM). The mathematical formulations of volume, surface and linear finite elements (FE) are presented. An analysis of the fulfillment of physical boundary conditions is carried out. The isoparametric FEs are specifically addressed. Depending on the geometric, material and load characteristics of the structures, approaches to the numerical modeling of them with volume, surface, and line FEs are presented, as well as the results of computer simulation, taking into account the particularities of individual FEs.

Practical work (tutorials) is performed in the programming language Wolfram Mathematica and ABAQUS computer code. Pre-knowledge of programming or working with Wolfram Mathematica and ABAQUS is not expected.

Content (Syllabus outline):

The aim of the course is to obtain knowledge on using FEM for solving mechanical problems, taking into account the particularities of individual FEs. The course covers the following topics: basics of geometry modeling (solid, surface, line geometric model), physical and mathematical modeling ( heat transfer, mechanical problems) and mastering the basics of numerical modeling of physical problems. We will present the theoretical background of FEM and the particularities of using solid, surface and line FEs. The main topics of the course are a simplification of the geometric model, the selection of the FE type and FE meshing, determination of the physical properties of the material and geometric properties of the FE and determination of initial, boundary and loading conditions. We will also learn how to present and analyze the computed results. All computations will be performed by computer codes Wolfram Mathematica and ABAQUS.

Response of students to the course:

The course has been very well accepted by the students.

Below we present some comments given by students in the students’ survey:

• This would be an appropriate course for all designers, because we obtained a good knowledge for mechanical analysis of structures by Finite Element Method using the ABAQUS and Wolfram Mathematica computer codes.
• Very good assistants and professor. I like the video lectures system and on-going tests. It is the advantage of video lectures that you can calmly study the topics by yourself and that you can look at explanations later.
• Excellent consistency of classroom tutorials (practical part) and lectures – the course is practically (real-life) oriented.
• Both the professor and assistants always take additional time for questions or further explanations.
• Very interesting course, understandable lectures. The performance of the course is excellent, it prepares you for the on-going work.

Comparison of rheological properties of different materials

Within the scope of the task, the rheological properties of various polymeric materials (also food, such as tomato concentrate, mustard, honey, mayonnaise, etc.) will be determined and compared. Based on rheological tests and taste, the classification of the materials and proposition of a quality control procedure, i.e. design a simple test to determine the properties of the material, will be assessed.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/sl/domov/

Crystallization kinetics of polymer materials

The properties of polymer products are defined also by the properties of feedstock materials. Moreover, the properties of polymeric materials (especially partially crystalline thermoplastics) can be changed by changing the manufacturing parameters. One of the important parameters is the rate of cooling of the material in the mold, which affects the degree of crystallinity of the polymer.

The aim of the study is to determine the influence of cooling rate on the formation of crystalline structure of polymeric materials. The task involves using the DSC method to determine the degree of crystallization and the optical microscope for observing the crystallization process.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/sl/domov/

Design of transportation data logger

During transportation a product can experience unexpected dynamic loads in form of impacts, drops and external vibration. Although this sudden load can appear during transportation only on rare occasions it can lead to significant damage of the product if the certain threshold is exceeded. Within this diploma thesis it is expected to study possibilities for construction of transportation load logger with affordable components (accelerometer, AD converter, digital signal writer) and with low energy consumption such that it would be able to operate during complete transportation process without a need for external power supply.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

High-temperature tribology – Evaluation of friction and wear

More and more applications nowadays operates at high temperatures and this arises also the important challenges in terms of tribological properties at these severe conditions. Within the scope of this work, the student will use Load-Scanner tribometer device, designed for testing the tribological properties of materials up to 800 °C. The work will include performing the tests, where load (contact pressure) and number of cycles will be changed at different temperatures in order to obtain general picture of the system, especially in terms at which conditions the significant wear of materials is obtained and how it can be evaluated (by measuring the wear volume or with gravimetric technique).

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

Influence of 3D printed thermochromic polymers on mechanical properties

Thermochromism is subclass of chromogenic phenomena, where visible optical properties change dependence on temperature. This phenomenon could appear in thermoplastics, duroplastics, gels, inks or paints. Colour change of thermochromic materials could be reversible or irreversible. Thermochromic systems are widely used as a carrier in various applications such as smart packaging, security printing, toys and marketing. Thermochromic pigments and their incorporation into mass market polymers have become increasingly important in the art and textile application. With use of 3D printer, a variety of different products could be made. We will focus on use of PLA filaments with incorporated thermochromic pigment. The mechanical properties of both commercial and extruded thermochromic polymer will be investigated.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/sl/domov/

Influence of Manufacturing Parameters on Piezoresistive Properties of 3D Printed Structures

An interest for additive manufacturing or 3D printing is increasing in recent years, since geometries unattainable with classical manufacturing processes, may be produced. On the other hand, parts created by additive manufacturing exhibit anisotropic properties and are highly dependent on many process parameters. The behaviour of additively manufactured parts is difficult to predict as a result. The goal of the presented thesis is to study the influence of manufacturing process on the piezoresistive properties of product, produced by fused deposition modelling. To achieve this goal, the student has to gain the basic knowledge of fused deposition modelling, design of experiments and piezoresistivitiy at first. Afterwards, the obtained knowledge has to be used, to design a systematic approach, to extract the influential manufacturing parameters by an already existing experiment.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

Measurement of the ZDDP tribofilm thickness using optical interferometer and atomic force microscope

Diamond-like carbon (DLC) coatings are very promising material for the use in many applications, in particular those operating under the most demanding boundary lubrication conditions, including automotive, where low friction and durability are of extreme importance. In order to introduce DLCs to automotive application, it is necessary that DLC coatings “synchronized” with conventional automotive lubricants where zinc dithiophosphates (ZDDPs) are key additives.

Numerous studies have focused on interactions between various DLCs and lubricants containing ZDDPs, however, the understanding of ZDDP-based lubrication of DLC is still far from understood.

Within this work the emphasis will be on the measurements of ZDDP tribofilm thickness, formed on the contacting surfaces of various DLC coatings (a-C:H and a-C:H:Si), after tribological tests performed under boundary lubrication conditions. The thickness measurement will be performed using two nano-technological tools, optical interferometer and atomic force microscope.

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

Measurements of thermal properties of polymeric materials using a simple device

The aim of the study is to measure the melting temperature and crystallization of various thermoplastic materials using a simple device. Within the scope, the device will be designed and manufactured. The task includes: design and manufacture of the device, testing of different thermoplastic materials and comparison of results with results, obtained with DSC method.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/sl/domov/

Planar kinematics identification using image-based methods and open-source tools

Image-based displacement measurement methods have in recent years been established as a valid alternative to many conventional techniques in experimental mechanics. The author of this thesis will have an opportunity to perform measurements using one of the most capable commercially available high-speed cameras and get familiar with some of the available open-source tools for image-based displacement measurements in the Python ecosystem. The goal is to perform an analysis of the planar kinematics of a select mechanical system, focusing on a software implementation using existing open-source tools.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

Rheological properties of multiply recycled HDPE material

The reuse of polymeric materials is important for sustainable development, where recycling plays an important role in reducing waste materials. Unfortunately, some of the properties of polymeric materials change during recycling process. The aim of the study is to determine how the rheological properties of high-density polyethylene (HDPE), which are associated with processing properties, change with repeated recycling.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/sl/domov/

Surface energy – Effect of surface preparation

Surface energy is relevant property of surfaces, since it defines the interaction of surface with surroundings, other surfaces, liquids, etc. In general the surface energy defines the chemistry of surface, and common approach to determine it is in-direct. Namely, contact angles measurements by employing different models is used. Since contact angle measurements are effected not only by surface chemistry itself, but also by other effects, such as environment, surface preparation/cleaning, surface roughness, this can significantly effect on measured values and thus on calculated surface energies. In this work student will prepare surfaces with different roughness and vary environment conditions and surface preparation (cleaning). The goal is to determine which of previously mentioned effects are relevant and should be paid more attention when determining the surface energy.

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

Thermal properties of multiply recycled HDPE material

The reuse of polymeric materials is important for sustainable development, where recycling plays an important role in reducing waste materials. Unfortunately, some of the properties of polymeric materials change during recycling process. The aim of the study is to determine (i) how the thermal properties of high-density polyethylene (HDPE) are changed by repeated recycling and (ii) when using recycled materials in the production process is it necessary to adjust the manufacturing parameters.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/sl/domov/

Topological optimization of the dynamic properties of the selected product

The aim is to acquire the knowledge of structure analysis using the topological optimization. For this purpose, it is first necessary to examine the existing state of the field, after which the topology optimization within the ANSYS software environment is performed on the selected product.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

A comparison of the limit of linear viscoelastic behavior LTVE boundary, determined by a static or dynamic test

The aim of the study is to compare the limit of linear viscoelastic behavior of polymeric material if it is determined by a static test or by a dynamic test. The task includes: a review of the relevant literature, the preparation of samples for static and dynamic testing, the measurement of LTVE at different temperatures on the modular rheometer, and an analysis of the results for determining the two limits of linear behavior.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Analysis of energy savings in the heating and cooling system using a heat pump and solar collectors

In the diploma thesis, a model and analysis of the current energy needs for cooling and heating for a real project (hotel) must be established using the TRNSYS simulation tool. Currently, the hot water is prepared with an oil boiler, and the cold is produced with water chiller (connection with the sea). In the second phase, the model needs to be upgraded and a heat pump should be included in it, which would simultaneously take advantage of heating and cooling. By parametric analysis, it is necessary to determine the best configuration of the system so that the energy savings achieved are the greatest.

Contact person: Assoc. Prof. PhD. Uroš Stritih

Webpage of the laboratory: http://lab.fs.uni-lj.si/los1/

Analysis of wear of contacting surfaces after graphene nanoparticles-based tribofilm removal

The use of several solid-lubricant nanomaterials as additives in lubricants present a promising new lubrication technology that combines the benefits of liquid lubrication with the physically based effect of nanoparticles. This would lead to a decrease in the toxic emissions and would eliminate the need for a tribochemical activation. In order to make such lubricants suitable for lubrication of various surfaces, e.g. DLC coatings, their tribological properties, such a friction and wear, need to be studied in detail.

Within this topic the emphasis will be on the wear analysis of contacting surfaces after tribological test performed under different conditions and upon tribofilm removal. The wear analysis will be performed using optical interferometer and scanning electron microscope.

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

Characterization and modelling of expanded polystyrene structures

Expanded polystyrene is one of most commonly used materials for packaging of sensitive products that must arrive undamaged from the production line to the costumer. Although its wide use the expanded polystyrene is a complex material showing nonlinear characteristics in relation to strain and strain rate. The purpose of thesis is to study the characteristics of expanded polystyrene of given density and implement them into numerical model. Further the modelling of expanded polystyrene structure’s response under static and impact loading is expected with nonlinear static and explicit transient analysis, respectively. The actual experiments of static and impact loading of expanded polystyrene should also be performed and compared to the numerical results.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

Characterization of the newly developed stirrer

By gas dispersing into liquids, the basic characteristics such as for example, the mixing power and mixing time and the rate of mixing are of crucial importance for the optimum execution of the technological process.

The work is an experimental – analytical nature in which include:

• Measurements of the basic characteristics of a newly developed mixer in
• standard and non – standard geometrical ratio of mixing vessel/stirrer for
• different hydrodynamic regimes.

The measurements will take place at the pilot experimental facility at the Laboratory for Fluid Dynamics and Thermodynamics.

Contact person: Assist. Prof. PhD. Andrej Bombač

Webpage of the laboratory: http://lab.fs.uni-lj.si/lfdt

Characterization of the two–phase flow regimes at the gas jet breakup in a liquid cross flow

The subject deals with one of the most geometrically simple solutions for the continuous mixing of gas and liquid phase. Gas is injected through the channel wall into the liquid cross flow. Different combinations of phase flows lead to the formation of different two-phase flow regimes, affecting the heat, mass and momentum transfer. Consequently, the knowledge of mechanisms for the transition between flow regimes is of key importance.

In the framework of this thesis, the development of a laser system is expected. The test section should be simultaneously through-lightened with several lasers to collect the data on flow regimes. By means of visualization, a flow pattern will be assigned to the particular shape of the laser system signal. In this way, a long time period observation will be possible, giving statistically relevant flow indicators. Special emphasis will be on the development of flow pattern maps and on the study of regime stability. The indicators of the flow regime transition would be used to evaluate the optimal heat and mass transfer in the device.

Contact person: Assist. Prof. PhD. Matjaž Perpar

Webpage of the laboratory: https://www.fs.uni-lj.si/en/faculty_of_mechanical_engineering/about_faculty/departments_and_laboratories/laboratories/2005012810071882/

Determination of the limit of linear viscoelastic behavior of partially crystalline polymer

The aim of the study is to determine the limit of linear viscoelastic behavior (LTVE) of partially crystalline polymer at different temperatures. The task includes: a review of the relevant literature, the preparation of cylindrical samples, the measurements of LTVE at different temperatures on the modular rheometer, and the analysis of the results for determining the limit of linear viscoelastic behavior.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Development and experimental validation of a heat exchanger in a dishwasher

One of the main targets of the Kyoto protocol is reduction of energy consumption. A lot of effort is focused on reducing the energy consumption in buildings, and household appliances are major users of energy. The goal of this thesis is to design a new heat exchanger and to predict heat exchanger geometry according to the dishwasher washing cycle in order to reduce the energy consumption. Heat exchanger configuration design will be made based on numerical results and number of experiments will need to be done as a validation of a numerical model.

Prerequisite knowledge: basic programming knowledge

Contact person: Sr. Dev. Nada Petelin

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/

Development of the data base system for »quasi« smart prediction of two-phase flow patterns in any selected system

The ability to predict two-phase flow patterns and transitions between them is one of the key research directions in the world scale. The approach to date was predominantly based on empirical flow pattern maps derived from the experimental research. Consequently, such maps are limited by the application and require the extrapolation of experimental results, which in most cases is not reliable. The solution is to develop new tools based on the flow pattern prediction utilizing the first principles of fluid dynamics and the description of two-phase flow, taking into account the nature of several scales. The long-term goal is to deepen the knowledge about the flow pattern development and to identify the key emergent parameters that would be helpful to build a general tool for the flow pattern estimation.

The task of the thesis is to establish a database system that would allow the systematic collection of experimental and numerical data from various research groups that are working within the ViR2AL Institute. The system should be scalable and adaptive, so it could combine data for different configurations of flow systems at a wide array of process parameters. Finally, the system should allow the storage of key two-phase flow parameters at the appropriated scales.

http://2phaseflow.org

Contact person: Assist. Prof. PhD. Matjaž Perpar

Webpage of the laboratory: https://www.fs.uni-lj.si/en/faculty_of_mechanical_engineering/about_faculty/departments_and_laboratories/laboratories/2005012810071882/

Digital-signal processing on the rotor-balancing device

The goal is to develop a user interface, which enables the digital-signal processing of data, on an existing rotor-balancing device. The PLC controller (Beckhoff) will be used to acquire the measured data, which will run simultaneously with the user interface. The user interface will be developed in the Python programming language and will enable the analysis of the measured data and the display of results.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

EHD friction of different lubricants – Experimental & models approach

Elasto-hydrodynamic lubrication is present in non-conformal contacts, such as rolling bearings, gear, cam followers, etc. These contact commonly operates in full-film lubrication regime, where viscous friction within the lubricating film defines overall friction performance of these contacts. Regarding the contact conditions (load, speed, strain rate) it is of the great importance the proper selection of lubricant. Especially relevant in this term are its rheological properties. In this work student will perform tribological tests on MTM tribometer device with different lubricants and at different conditions to obtain coefficient of friction values. In the second part he will study different theoretical models for modelling EHD friction (Eyring, Carreau-Yasuda) and try to establish (existing and modified) models for measured friction results

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

Experimental analysis of different enhanced evaporators on heat pump performance

Heat pumps, or more precisely, cooling cycles have been subjected to numerous optimizations and improvements. One of means to enhance the cooling cycle of a heat pump is to lower the temperature difference between the refrigerant temperature and the heat source. This is possible by enhanced evaporators which use different techniques in order to achieve this goal.

Tasks: Besides literature survey, an extensive set of experimental work should be done by using several different types of heat pump’s evaporators. Furthermore, the student would determine the influence of different enhanced evaporators on the operation of the entire cooling cycle with respect to the normal -unmodified evaporator.

Contact person: Assist. PhD. Primož Poredoš

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/

Experimental and numerical study on condensation of water vapor in the presence of air on various surfaces

Condensation of water vapor in the presence of air is completely altered in terms of wall heat flux and condensate mass flux. The fact is that the air molecules near the liquid – vapor interface act as an additional resistance towards condensation of water molecules in the air – water vapor mixture. The research in this domain has been accelerated in the 80’s and 90’s due to several dangerous events in the nuclear reactors cooling systems.

Tasks: Besides literature survey an extensive set of experimental work should be done. Those measurements would provide a means for validation numerical models. The student would determine the influence of air mass fraction, temperature of moist air as well as temperature difference (moist air, cold surface) on the intensity of condensation heat fluxes and rates of condensed water.

Contact person: Assist. PhD. Primož Poredoš

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/

Experimental and theoretical analysis of the influence of fiber content on the mechanical properties of composite materials

The objective of the study is to improve (theoretically and experimentally) the predicted mechanical properties of composite material, considering the actual proportion of fibers in the composite. The task includes: a review of relevant literature, the production of composite samples, the use of micromechanical models for forecasting mechanical properties, the testing of composite samples, and the improvement of micromechanical models.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Experimental determination and modelling of yield stress of composite materials with a high proportion of solid particles

Within the assignment, the yield stress of composite materials with a high proportion of solid particles will be determined at different temperatures and different concentrations of solid particles. The second part of the task is designed to model yield stress using existing models.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Experimental determination of dynamic material properties of polymeric materials

The aim of the study is to determine the dynamic material properties of various polymer materials in a wide frequency range by performing tests at different temperatures. Within the assignment, it is necessary to: prepare samples for testing, perform DMA tests on a rotary rheometer at different temperatures, compose a master curve under the reference conditions using a frequency-temperature superposition, and compare the results between different polymer materials.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Experimental modal analysis with high-speed camera

Experimental modal analysis is the procedure for identification of modal parameters (natural frequency, damping coefficient) based on measurement of the vibration response of the structure. Response measurement with high-speed camera is among the new approaches that produces spatially dense information, however some problems must be overcome. The goal of the thesis is to explore different options for displacement identification based on high-speed camera video and research appropriate modal identification approaches. During the thesis, an experiment with high-speed camera will be conducted. The identification of displacements and modal parameters will be implemented in Python programming environment.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

Influence of 3D printed thermochromic additives on rheological properties of melt and mechanical properties of solid polymer

Thermochromism is subclass of chromogenic phenomena, where visible optical properties change dependence on temperature. This phenomenon could appear in thermoplastics, duroplastics, gels, inks or paints. Colour change of thermochromic materials could be reversible or irreversible. Thermochromic systems are widely used as a carrier in various applications such as smart packaging, security printing, toys and marketing. Thermochromic pigments and their incorporation into mass market polymers have become increasingly important in the art and textile application. With use of 3D printer, a variety of different products could be made. We will focus on use of PLA filaments with incorporated thermochromic pigment. The rheological, thermal, and mechanical properties of both commercial and extruded thermochromic polymer will be investigated.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Material failure of dynamically loaded polymeric products

In many applications, products made of polymeric materials are subject to dynamic (cyclic) loads (typical example: polymer gears). In such cases, material failure often occurs as deformation in the product accumulates over time. The aim of this study is to compare the experimentally measured and predicted material failure due to the accumulation of deformations of dynamically loaded polymeric materials. For this purpose, the candidate will use the existing model for predicting the accumulation of deformations and compare it with the experimentally measured deformation of the material.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Measurement of adhesion and friction force between a graphene platelet and various engineering surfaces

The use of several solid-lubricant nanomaterials as additives in lubricants present a promising new lubrication technology that combines the benefits of liquid lubrication with the physically based effect of nanoparticles. This technology would lead to a decrease in the toxic emissions and would eliminate the need for a tribochemical activation. In order to understand lubrication properties as well as effect of various nanoparticles on macro-tribological performance (friction and wear) of the investigated contacts, tribological properties on nano-scale, such as adhesion, friction force, mechanical properties, need to be understand in detail as well.

Within this work the main emphasis will be on the measurements of adhesion and friction force between a graphene platelet and various surfaces, such as various steel, DLC-coatings, ceramics, etc., on sub-nano scale. The measurements will be performed by atomic force microscope.

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

Modelling and experimental determination of dynamic material properties of polymeric materials

The aim of the task is to determine the dynamic material properties of various polymer materials in a wide frequency range by testing materials at different temperatures. Within the assignment, it is necessary to: prepare samples for testing, perform DMA tests on a rotary rheometer at different temperatures, compose a master curve under the reference conditions using a frequency-temperature superposition, and compare the results between different polymer materials.

Additionally, it is necessary to use well-known mathematical models for modelling frequency-dependent material properties and to make a comparison between models in order to determine which of the models better predicts the properties.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Modelling and optimization of drying process in a dishwasher

Two of the most important selling points for products like dishwasher are their power consumption and final dryness of the kitchenware. The current dishwasher drying system heats water to a high temperature in the last washing step in order to increase temperature of the kitchenware and therefore increase drying process. However, this is not the most effective way, due to small mass of plastic kitchenware and as a resulting final dryness is not satisfying. Few options are available to improve current drying system, which will be evaluated in the thesis. The aim of this thesis is to define a completely new drying system for a dishwasher and experimentally characterize it with aim to satisfy the final dryness of kitchenware.

Prerequisite knowledge: basic programming knowledge

Contact person: Assist. PhD. Katja Klinar

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/

Modelling the Mechanical Behaviour of 3D Printed Structures

In recent years, a large amount of scientific papers focuses on additive manufacturing or 3D printing, due to reduced material costs and possibility to produce unusual complex geometries, as opposed to conventional technologies. However, the prediction of mechanical behaviour of such structures is difficult, since they possess on manufacturing parameters dependent, anisotropic properties. The goal of the thesis is to create and experimentally validate a mechanical model of the structure produced by fused deposition modelling. In order to achieve this goal, the student has to study the literature which tackled this problem and afterwards create appropriate analyitical/numerical model of the structure. In order to validate the model, an experiment has to be designed and created at the end.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: http://www.ladisk.si/

Numerical modelling of digital microfluidics

Microfluidics deal with the flow of liquids inside micrometer-sized channels. In order to consider it microfluidics, at least one dimension of the channel must be in the range of a micrometer or tens of micrometers.

Although most microfluidic devices are based on continuous flow of liquids in microchanells,  there has  been an increasing interest for the past couple of years in devices that rely on manipulation of discrete droplets using surface tension effects. One such technique is ElectroWetting On Dielectric (EWOD), which is based on wettability of liquids on a dielectric solid surface by varying the electrical potential.

The focus of this research will be to develop electrohydrodynamic numerical model of EWOD mechanism. First objective is to model the change in the contact angle with surface of the droplet when the electric potential is applied or turned off. The electrowetting effect in the fluid flow dynamics will then be directly introduced through the equations from electrostatics and coupled with the Navier-Stokes equations, respectively. Namely, this transition to the fluid-electro-dynamics will be the second task of the electrohydrodynamic modelling. The main and final goal is to numerically analyze different geometries and electrical properties of electrodes and droplets, which will allow for a fast actuation of the droplets.

Contact person: Assist. PhD. Urban Tomc

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/

Optimal abrasive flow rate in abrasive water jet machining

Experimental work to determine the optimal abrasive flow rate for two types of materials of several thicknesses at the given pressure and combination of water nozzle and focusing tube. The criteria is minimum machining costs. Higher abrasive flow rate enables higher machining speed, but also causes higher machining costs per working hour. The former relation is not linear whereas the latter is linear.

Contact person: Assoc. Prof. PhD. Joško Valentinčič

Webpage of the laboratory: http://www.fs.uni-lj.si/lat

OVERHEATING REDUCTION OF BUILDINGS BY INTRODUCING THE ACTIVE-PASSIVE BUILDING SYSTEJM (ANSYS FLUENT)

One of the consequences of global warming is also an overheating of buildings which reflects in increase of ambient temperatures. In order reduce the energy needed for cooling, passive technologies accumulating the excess heat from the space by changing their phase are introduced. Phase change materials (PCM) can be applied on the external wall. However, due to material properties, there is a risk that the material without nighttime ventilation would not successfully discharge and released it latent heat. To enhance the performance/discharge the material completely, a strategy for air based active PCM is proposed called ‘ventilated layer’. The parametrical analysis of the ventilated layer (air velocity, flowrate, inlet diffusor, geometry of the system) will be studied with ANSYS Fluent.

Contact person: Assoc. Prof. PhD. Uroš Stritih

Webpage of the laboratory: http://lab.fs.uni-lj.si/los1/

OVERHEATING REDUCTION OF BUILDINGS BY INTRODUCING THE ACTIVE-PASSIVE BUILDING SYSTEJM (TRNSYS)

One of the consequences of global warming is also an overheating of buildings which reflects in increase of ambient temperatures. In order reduce the energy needed for cooling, passive technologies accumulating the excess heat from the space by changing their phase are introduced. Phase change materials (PCM) can be applied on the external wall. However, due to material properties, there is a risk that the material without nighttime ventilation would not successfully discharge and released it latent heat. To enhance the performance/discharge the material completely, a strategy for air based active PCM is proposed called ‘ventilated layer’. The performance of such system will be tested with TRNSYS software where also a parametrical analysis of the mechanical components will be investigated.

Contact person: Assoc. Prof. PhD. Uroš Stritih

Webpage of the laboratory: http://lab.fs.uni-lj.si/los1/

Phase-based displacement identification in digital images for vibration measurement

In recent years, phase-based methods for displacement identification in digital images have substantially gained in popularity. State of the art approaches to phase-based motion identification are already considered a valid alternative to gradient-based methods (e. g. optical flow) also in vibration measurement applications. Combined gradient and phase-based approaches aim to extract as much motion information from high-speed digital video as possible, improving the signal-to-noise-ratio of image-based measurements. The goal of this thesis is to survey the available tools for spatiotemporal phase calculation in digital images within the Python framework and implement a phase-based displacement identification algorithm, as well as assess the possibility of extending this algorithm into a phase-based motion magnification application.

Contact person: Prof. PhD. Janko Slavič

Webpage of the laboratory: www.ladisk.si

Set-up of optical system for determination of forming limit diagram by Marciniak test

Determination of formability limits is a crucial task in evaluation of sheet metal materials. For this purpose two main procedures are used: Nakazima test and Marciniak test. The Marciniak test should be evaluated in the presented master thesis.

In order to evaluate the strains on the sheet metal the optical system combined with Marciniak test exists in the Forming Laboratory. The test is currently used on pre-printed shapes. With upgraded picture detection and evaluation the strain distribution on random-distributed pattern should be evaluated. In the master thesis the tool for data acquisition and evaluation has to be build based on available image recognition tools.

Preliminary knowledge: programming skills, data acquisition, Labview

Contact person: Assoc. Prof. PhD. Tomaž Pepelnjak

Webpage of the laboratory: https://www.fs.uni-lj.si/lap

Solid-state thermal rectifier

Thermal rectification is a phenomenon in which thermal transport along a specific axis is dependent upon the sign of the temperature gradient or heat current. Currently several mechanisms for thermal rectification have been proposed including surface roughness/flatness at material contacts, thermal potential barrier between material contacts, difference in temperature dependence of thermal conductivity between dissimilar materials at a contact, nanostructured asymmetry, anharmonic lattices and quantum thermal systems. The research is based on development of numerical model for characterization of thermal rectification in different materials and geometries.

Prerequisite knowledge: basic programming knowledge

Contact person: Assist. PhD. Katja Klinar

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/

Surface energy at high temperature

Surface energy is relevant property of surfaces, since it defines the interaction of surface with surroundings, other surfaces, liquids, etc. Common approach to determine it is by contact angles measurements by employing different models is used. However this works well at ambient temperature, but he problems are at elevated temperatures. Namely, if we have temperature difference between model liquid (for wetting test) and surface as well as environment, in addition we have thermo-dynamic process which can significantly effect on wetting and thus on calculated surface energy. In this work, student will in first part study relevant literature for surface energies measured by contact angles at elevated temperatures in terms to get overall impression of current state of development, main issues and problems. In second part student will perform tests on contact angle goniometer, with heated samples and liquid and try to find correlation compared to measured values of contact angles as well as calculated surface energies at ambient conditions.

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

The impact of recycling on the mechanical, thermal and rheological properties of HDPE polymer

Re-use of polymeric materials is important for sustainable development, where recycling plays an important role in reducing waste materials. However, some of the properties of polymer materials change with recycling. The aim of the task is to determine how multiple recycling affects the mechanical, thermal and rheological properties of HDPE material.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

The influence of graphene nanoparticles as oil additives on tribological properties of mixed contacts with steel and various DLC coatings

The use of several solid-lubricant nanomaterials as additives in lubricants present a promising new lubrication technology that combines the benefits of liquid lubrication with the physically based effect of nanoparticles. This would lead to a decrease in the toxic emissions and would eliminate the need for a tribochemical activation. In order to make such lubricants suitable for lubrication of various surfaces, e.g. DLC coatings, their tribological properties, such a friction and wear, need to be studied in detail.

Within the scope of this work the emphasis will be on the investigation of macro-lubrication behavior of graphene-based additives in oil as well as their tribological effects (friction and wear) on various contact configurations with steel and DLC coatings (steel/a-C:H and steel/a-C:H:Si).

Contact person: Prof. PhD. Mitjan Kalin

Webpage of the laboratory: https://www.tint.fs.uni-lj.si/

The influence of moisture on time dependent behavior of composite materials with short glass fibers

Short glass fibers in a thermoplastic polymer matrix improve the mechanical properties of the material (tensile strength, impact strength, …). The question is, however, how glass fibers affect the time dependent behavior of the composite material, especially if the composite material is exposed to moisture.

The aim of the task is to determine the long-term time-dependent mechanical properties of the composite material and to determine the influence of moisture on the time-dependent behavior of this composite.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

The prediction of the effect of short fiberglass fraction on time-dependent behavior of composite material

Short glass fibers in a thermoplastic polymer matrix improve mechanical properties of the material (tensile strength, impact strength, …). The questions are, however, (i) how glass fibers affect the time-dependent behaviour of the composite material, (ii) what is the effect of increasing the fraction of the fibers on these properties, and (iii) how the fiber orientation affects time-dependent properties.

It is necessary to compare the time-dependent properties of a pure thermoplastic polymer with a composite material with different fiber orientations and fiber concentrations. Based on experimentally determined properties, it is necessary to propose a model, which would effectively predict such behaviour.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Use of neural networks to determine the impact of the process conditions of 3D printed materials on their mechanical properties

3D printed products are increasingly found in more demanding industries, such as: medicine, space technology, aerospace industry, etc. It is known that the manufacturing bowls can significantly influence the structure of the polymeric material and, consequently, its mechanical properties. The goal of the task is to determine the link between the production parameters (print speed, print temperature, cooling rate and substrate temperature) depending on the production parameters using neural networks. The required knowledge of neural networks is given to the candidate during the course of the task.

Contact person: Assist. Prof. PhD. Lidija Slemenik Perše

Webpage of the laboratory: http://web.fs.uni-lj.si/cem/

Use of PCM (phase change materials) as a heat storage for one or more household appliances

A phase change material (PCM) is a substance, which is capable of storing and releasing large amounts of energy and can serve as a latent heat storage system. Heat is absorbed or released when the material changes from solid to liquid phase and vice versa. For household appliances is important that material has strong supercooling effect, since this effects ability to store latent energy partly loss free up to 2 days or more.

The purpose of this research will be to theoretically analyse suitable PCM materials and experimentally characterize it at different conditions, to determine material stability and thermal properties. The candidate will try to simulate similar conditions in one or more household appliances to see how the system responds and how much energy could be recovered with implementation of PCM materials.

Prerequisite knowledge: basic programming knowledge

Contact person: Sr. Dev. Nada Petelin

Webpage of the laboratory: https://lahde.fs.uni-lj.si/en/home/