The University of Ljubljana has announced its most outstanding research achievements for 2024 as part of University Week. Among the winners was a team of researchers from the Faculty of Mechanical Engineering who were recognised for developing the innovative Hypereg heat regenerator, which is designed to regenerate heat more efficiently at high frequencies.
The achievement is the result of the work of researchers: Prof. Dr. Andrej Kitanovski (holder), Assist. Prof. Dr. Katja Klinar, Assoc. Prof. Dr. Franc Majdič, Dr. Jure Mencinger, Assist. Prof. Dr. Izidor Sabotin, Assist. Dr. Urban Tomc and Assoc. Prof. Dr. Joško Valentinčič.
Researchers at UL FME have invented a new concept for a heat regenerator that can improve the power density of the devices in which it is used many times over. These include heat pumps, chillers and power generators based on gas or calorific thermodynamic cycles. A regenerator is a heat storage and transfer device consisting of a solid matrix through which a working fluid oscillates.
Photo: Katja Kodba, STA
The principle of the regenerator has been known for almost 100 years, but has limited applications. At higher frequencies (i.e. more cycles of the fluid flow oscillations), excessive pressure losses occur and the time interval for heat transfer along the regenerator becomes too short.
The new regenerator concept, called Hypereg, solves the problem of excessive pressure losses, thus extending the use of regenerators to higher operating frequencies. The Hypereg is hydraulically divided into a number of smaller compartments in which the fluid oscillates along the solid (as in a conventional regenerator) and also introduces an external fluid flow transverse to these compartments. The coordinated fluid flow in all parts of the Hypereg therefore allows efficient solid-liquid heat recovery even at higher frequencies, which in turn allows a significant increase in the power density of both caloric and gas circulating devices, including thermoacoustic and mechanical striling technologies.
Congratulations to these researchers for their outstanding contribution to the advancement of science and technology!
Photo: Katja Kodba, STA