中文摘要：

本文通过建立微型燃气轮机CW（CrossWavy）原表面回热器热结构耦合有限元分析模型，对其在设计工况下运行后的应力进行了有限元分析，验证了回热器所选材料的可靠性，并分析了压比和燃气入口温度对回热器的应力影响。分析结果表明：不考虑热应力，只计及压力时，回热器燃气出口侧最大应力和应变高于燃气进口侧最大应力和应变；与之相反，计及热应力时，在压力和温度耦合作用下，回热器燃气进口侧最大应力和应变高于燃气出口侧最大应力和应变；无论是计及热应力还是不考虑热应力，空气通道的波谷处应力最大，并且应力沿波谷处左右对称分布，计及热应力后，其最大应力增长较大，对应各处增幅最高达到34．1％；回热器空气通道向燃气通道侧变形，空气通道变大，燃气通道减小；随着空气侧和燃气侧压比的增加，回热器通道的最大应力也随之增加，当压比增加到8．4时，已达到换热片材料的强度极限；当燃气与空气出口温度不变、回热度减小时，随着燃气入口温度增加，最大应力随之增加，燃气入口温度每增加50K，回热器最大应力增加约2．3MPa。研究结果为回热器的设计提供了一定的参考依据。

英文摘要：

In this paper, two-dimensional thermal-structural coupled model of cross wavy primary surface recuperator in micro-gas tur- bine system was built. Stress of designing working condition were analyzed by FEA （Finite Element Analysis）. The material reliability of recuperator was verified. The influence of pressure ratio and gas inlet temperature on the stress and displacement was analyzed. The analysis results show that the maximum stress and strain of gas outlet exceed those of gas inlet without thermal stress considered. With the coupled effect of pressure and temperature, the maximum stress and strain of gas inlet exceed those of gas outlet when the thermal stress is considered. Whether thermal stress considered or not considered, the stress in wave hollow of air channel is the maximum. The stress distributes symmetrically along the wave hollow of air channel. With thermal stress considered, the maximum stress increases obviously, the maximum increasing amplitude is 34.1%. The channel of air moves toward that of gas. As a result, channel of air swells and that of gas shrinks. As the pressure ratio between the air and the gas goes on, the maximum stress of recuperator increases. When pressure ratio is 8.4 , the maximum stress is equal to the limit of material strength. As the gas inlet temperature goes on and the thermal ratio keeps constant, the maximum stress increases a little. When gas inlet temperature improves 50 K, the maximum stress of recuperator improves about 2.3 MPa. The research results can be used as the reference for the designing of recuperator.