【摘要】 为研究工况参数偏离设计点对某高膨胀比透平叶栅性能的影响，采用RANS、LES数值模拟并结合叶栅实验，分析了进口温度、落压比和攻角变化下该叶栅的内部流动机制。结果表明：相比进口温度，落压比和攻角的偏离对叶栅等熵效率的影响更为显著。当落压比降低时，边界层损失增加，同时由于横向压差加剧，通道涡二次流损失增加；而当落压比升高时，尾迹损失和冲波损失增加。正攻角未引起明显边界层分离和尾迹变化，但通过改变马蹄涡鞍点和增大横向压差，导致通道涡二次流损失增加。研究为优化透平变工况运行性能提供了理论依据。更多还原

【Abstract】 To investigate the effects of operating conditions deviating from design points on the performance of a high-expansion ratio turbine stator cascade, RANS and LES numerical simulation were employed in conjunction with cascade experiments to analyze the cascade internal flow mechanisms under varying inlet temperature, pressure ratio, and incidence angle. The results reveal that compared to inlet temperature deviations, variations in pressure ratio and incidence angle have a more significant impact on the cascade’s isentropic efficiency. A reduction in pressure ratio leads to increased boundary layer losses and augments secondary flow losses due to intensified lateral pressure differences. While, an increase in pressure ratio results in higher wake and shock wave losses.Positive incidence angles do not induce noticeable boundary layer separation or wake variations but alter the horse-shoe vortex saddle point and increase lateral pressure differences, thereby boosting secondary flow losses. This study provides theoretical support for optimizing turbine performance under variable conditions.更多还原