Evaluation of the Cross Corrugated and Some Other Candidate Heat Transfer Surfaces for Microturbine Recuperators

Abstract

To achieve high thermal efficiencies, 30 percent and higher, for small gas turbines a recuperator is mandatory. As the recuperator represents 25–30 percent of the overall machine cost, efforts are now being focused on establishing new low-cost recuperator concepts for gas turbine engines. In this paper the cross corrugated (CC), also called chevron pattern, heat transfer surface is reviewed to assess its thermal and hydraulic performance and compare it to some other candidate surfaces for a 50 kW microturbine. The surfaces may be categorized into three primary surface types and one plate-fin type. Design calculations of a recuperator heat transfer matrix using these surfaces enable direct comparison of the recuperator matrix volumes, weights and dimensions. It is concluded that the CC surface has great potential for use in recuperators of the future.