The Free-Piston Stirling engine (FPSE) is of interest for many research in aerospace due to its advantages of long operating life, higher efficiency, and zero maintenance. In this study, a 1-kW FPSE was proposed by analyzing the requirements of Space Reactor Power Systems (SRPS), of which performance was evaluated by developing a code through the Simple Analysis Method. The results of SAM showed that the critical parameters of FPSE could satisfy the designed requirements. The heater of the FPSE was designed with the copper rectangular fins to enhance heat transfer, and the parametric study of the heater was performed with Computational Fluid Dynamics (CFD) software STAR-CCM⁺. The Performance Evaluation Criteria (PEC) was used to evaluate the heat transfer enhancement of the fins in the heater. The numerical results of the CFD program showed that pressure drop and Nusselt number ratio had a linear growth with the height of fins, and PEC number decreased as the height of fins increased, and the optimum height of the fin was set as 4 mm according to the minimum heat exchange surface area. This paper can provide theoretical supports for the design and numerical analysis of an FPSE for SRPSs.

自由活塞斯特林发动机 (FPSE) 因其使用寿命长、效率更高和零维护等优点而受到航空航天领域许多研究的关注。在这项研究中，通过分析空间反应堆动力系统 (SRPS) 的要求，提出了 1 kW FPSE，并通过简单分析方法开发代码来评估其性能。SAM结果表明，FPSE的关键参数满足设计要求。FPSE 的加热器设计有铜矩形翅片以增强传热，并使用计算流体动力学 (CFD) 软件 STAR-CCM ⁺对加热器进行参数研究. 性能评估标准 (PEC) 用于评估加热器中翅片的传热增强。CFD程序的数值结果表明，压降和努塞尔数比随着翅片高度的增加呈线性增长，PEC数随着翅片高度的增加而减小，根据公式，翅片的最佳高度为4 mm。最小热交换表面积。本文可为SRPS的FPSE设计和数值分析提供理论支持。