斯特林循环汽油机尾气余热回收加热器的试验研究及结构优化

Heater Test Research and Structural Optimization Based on Stirling Cycle Gasoline Exhaust Heat Recovery System

基于斯特林循环汽油机尾气余热回收系统,优化了关键部件加热器的结构。首先,汽油机工作时,加热器表面的温度降低;其次,加热器计算流体动力学(Computational Fluid Dynamics,CFD)的仿真分析表明,内部结构的不合理是导致加热管表面温度分布不均、加热器的吸热性能不好、尾气热利用率低的重要原因;最后,优化换热腔结构可显著改善加热器管温度分布不均,提高换热管的平均温度。仿真结果表明,加热器吸热量随转速升高和工作压力增大而线性增加,对斯特林尾气回收系统如何提高加热器吸热性能具有积极意义。

Based on the exhaust heat recovery system of Stirling cycle gasoline engine, the structure of the key component heater is optimized. Firstly, when the gasoline engine is working, the temperature of the heater surface decreases. Secondly, the simulation analysis of Computational Fluid Dynamics(CFD) of the heater shows that the unreasonable internal structure is an important reason for the uneven temperature distribution on the surface of the heating pipe, the poor heat absorption performance of the heater and the low heat utilization rate of the exhaust gas. Finally, optimizing the structure of the heat exchange chamber can significantly improve the uneven temperature distribution of the heater tube and increase the average temperature of the heat exchange tube. The simulation results show that the heat absorption capacity of the heater increases linearly with the increase of rotating speed and working pressure, which is of positive significance to how to improve the heat absorption performance of the heater in the Stirling tail gas recovery system.