Abstract
Heat transfer characteristics of regenerators are studied in order to clarify the effect of entrance and exit areas which are usually smaller than the cross-sectional area of matrix. The change of the air temperature at exit is measured for different entrance areas and stack thicnesses using an abrupt heating method. The result is compared with theoretical one which is calculated based on an axially-symmetric irrotational flow model and a simple convective heat transfer model. This comparison brings two experimental numbers of a representative time and a number of transfer unit under uniform flow. These numbers agree with ones calculated from respective definitions and therefore the experimental results are expained by the models mentioned above. However, some difference is observed when the entrance area and stack thickness are small. This will be mainly due to the effect of heat conduction in matrix neglected in the present model.
