Numerical and Experimental Investigation of Transient Response of Primary Surface Recuperator Due to Flow Rate Step

Abstract

Temperature transient response of a primary surface recuperator (PSR) is investigated when mass flow rate is subjected to a sudden change. Based on the conservation theorem of energy and structural characteristics of PSR, its unsteady differential equations about the transient temperatures of fluids and solid wall in the recuperator are presented. The numerical results are validated by comparison against the experimental data. The influence of flow rate step magnitude on the transient behavior is studied by maintaining the initial steady states. The influence of the thickness of the corrugated heat transfer foils in the PSR on the temperature transient response is also discussed. The comparative results show the low-weight PSR has much more advantages in transient response than traditional heat exchanger because its time constant of solid wall is much less than shell-tube or plate-fin heat exchanger. PSR is very fit for application to the marine or vehicle gas turbine engine that works under the changeful conditions.