Heat Transfer Intensification in Recuperative Heat Exchangers of the Stirling Engine

Abstract

The non-stationary mode of movement of the working fluid flow in the Stirling engine causes serious difficulties in the design of heat exchangers. In most cases, the operation of conventional commercial heat exchangers is considered under steady-state flow conditions with relatively slowly varying parameters. Another situation is observed in Stirling engines, where the working fluid flow mode is characterized by significant changes in pressure, density and flow rate, the direction of which changes twice per cycle. These circumstances significantly complicate the design of regenerators and other heat exchangers for Stirling engines. The results of a theoretical and experimental study of recuperative heat exchangers in the Stirling engine system and possible ways to improve the efficiency of heat transfer in order to increase power and efficiency are considered in this article. A method of comparative evaluation of heat exchange surfaces efficiency is proposed under conditions of their operation in the engines with external heat supply system.

Keywords

• recuperative heat exchanger
• stirling engine
• engine with external heat supply