斯特林发动机中回热器性能研究

斯特林发动机中回热器的有效性对斯特林发动机的整机性能有较大的影响。文中通过商业软件FLUENT的动网格功能模拟了回热器内部流场的交变流动以及流体工质与回热器之间的往复式热量交换,进而捕捉斯特林发动机运行时,回热器基体在高速交变气体流场中温度场的变化规律。研究结果表明,回热器的有效性和流阻损失随孔隙率的增大而减小,随长径比的增大而增大。因此在设计斯特林发动机时需要综合考虑回热器的孔隙率和长径比。

Performance of Regenerator of Stirling Engine

The efficiency of regenerator of Stirling engine influences mightily the performance of Stirling engine. The periodical oscillating flow in the regenerator and the heat transfer characteristics between fluid and regenerator are modeled in two dimensions by the dynamic mesh model of the commercial CFD software FLUENT. Moreover, the regenerator temperature field can be also simulated when the Stirling engine begins to work. The results show that the effectiveness of regenerator and loss of flow resistance decrease with the increase of the porosity, and increase with the increase of length-diameter ratio. Therefore the porosity and length-diameter ratio need to be selected according to the overall design requirements of the engine.