Effectiveness enhancement of a thermal regenerator in an oscillating flow

Abstract

An experimental study has been carried out to investigate the effects of the combination of regenerator materials on the regenerator effectiveness in an oscillating flow. Three types of regenerators are considered in this study. A homogeneous regenerator is made of a wire mesh number 120. Two heterogeneous regenerators are made of the combination of three kinds of wire mesh numbers (60, 120, 200), (200, 120, 60) in order. The average porosities of all these regenerators are kept at 0.7 in the experiment. Transient temperature variations inside the regenerator as well as pressure differences between the both ends of regenerator are measured for the several oscillating frequencies. The results obtained indicate that not only the regenerator effectiveness can be enhanced, but also that the pressure loss is decreased with the proper combination of regenerator materials even though the average porosity of the regenerator is not changed. It is also found that the pressure loss through the regenerator is increased with an increase in the frequency of oscillating flow, while the regenerator effectiveness is decreased. (C) 1998 Elsevier Science Ltd. All rights reserved.