Abstract:

As a closed cycle engine heated with external heat source, Stirling engine coupled with high-temperature heat pipe could provide power output resulted from heat energy in certain cases. In this paper, the method of the thermal resistance network and adiabatic analysis method are used to analyze the high temperature heat pipe and Stirling engine respectively. Through the calculation of the heat flow between the heat pipe and the engine, the coupling operation characteristics of the two are studied. With the group of a stirling engine and a liquid metal heat pipe which could meet the input requirements of the Stirling engine, the operating characteristics of coupled Stirling engine system are analyzed, and the starting characteristics and the change of output power with the temperature of heat source are studied. The results show that at a heat source temperature of 1000 K, the Stirling system studied in this paper reaches a steady state after 400 s and can provide output power about 101 W. As the heat source temperature increases, the power loss in the engine will increase accordingly, making the growth of the engine output power slower. When the heat pipe wall thickness is changed, the engine output power first increases and then decreases. The optimal heat pipe wall thickness under this working condition is 7 mm.

Key words: numerical simulation, model, dynamic simulation, heat conduction, Stirling engine, coupling characteristics

摘要：

斯特林发动机作为一种外部供热的闭式循环发动机，与高温热管耦合在一些特定场合能够实现热功转换目标。采用热阻网格法和绝热分析法分析高温热管和斯特林发动机，通过对热管与发动机间的热流等进行迭代计算，分析二者间的耦合运行特性。基于一个斯特林发动机及能够满足其输入热能需求的高温热管组合，分析了耦合情况下斯特林发动机的运行特征，包括斯特林发动机的启动特性以及输出功率随热源温度的变化。结果表明，在1000 K的热源温度下，斯特林系统在400 s后达到稳态，能够提供约101 W的稳态输出功率；随着热源温度的升高，发动机内的功率损失会随之升高，使得发动机的输出功率增长趋缓；改变热管壁厚，发动机输出功率先增大后减小，在所研究工况下的热管管壁最优厚度为7 mm。

关键词: 数值模拟, 模型, 动态仿真, 热传导, 斯特林发动机, 耦合特性