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对汽轮机叶栅中的自发凝结两相流动进行了数值模拟,气相采用N-S方程,液相凝结过程采用积分方法求解构造的多阶参数。计算结果显示,与过热蒸汽流动相比,湿蒸汽流动会在叶栅吸力面产生明显的边界层分离现象,所产生的损失不应被忽略。液相参数分布对叶型吸力面型线敏感。型线变化直接影响成核区分布,并通过影响尾迹强度决定下游主流的不平衡状态。分析了叶型变化对成核过程、边界层分离和尾迹涡强度的影响。通过数值研究,提供了减少因凝结产生的各种损失、设计高效湿蒸汽级的方法。
The self-condensing two-phase flow in the steam turbine cascade was numerically simulated, the N-S equation was adopted for the gas phase, and the integral method was used to solve the multi-order parameters of the structure. The calculated results show that the flow of wet steam will cause obvious boundary layer separation on the suction side of the cascade compared with the superheated steam flow, and the losses should not be neglected. The liquid phase parameter distribution is sensitive to the leaf suction surface profile. The change of shape line directly affects the distribution of nucleation area and determines the unbalanced state of downstream mainstream by influencing the strength of wake. The influence of the leaf pattern on nucleation, boundary layer separation and wake vortex intensity was analyzed. Through numerical studies, a method of designing efficient wet steam stages is provided that reduces the various losses caused by condensation.