叶栅形状变化对自发凝结影响的数值研究  

Numerical Study on Impacts of Blade Profile Modification on Homogeneous Condensation

作　　者：王智[1] 安连锁[1] 韩中合[1] 

机构地区：[1]电站设备状态监测与控制教育部重点实验室(华北电力大学),河北省保定市071003

出　　处：《中国电机工程学报》2009年第35期125-130,共6页Proceedings of the CSEE

基　　金：国家自然科学基金项目(50676031)~~

摘　　要：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 spontaneous nucleation flow in a turbine cascade was numerically studied. The model was implemented within a full Navier-Stokes viscous flow solution procedure, and the process of condensation was calculated by the quadrature method of moments. Results shows in wet steam flow, degree of boundary layer separation is greater than in superheated steam flow and the loss can＇t be neglected. The impacts of blade profile modification on nucleation and degree of boundary layer separation were numerical studied. The liquid phase parameter distribution is sensitive to the suction side profile of turbine cascade, which impacts the nucleation rate distribution leading to different droplet distributions and affects the degree of boundary layer separation. The numerical study provides a practical design method for turbine blade to reduce wetness losses, A method for controlling homogeneous nucleation and reducing degree of flow separation in high-speed transonic wet steam flow is presented.

关 键 词：湿蒸汽 两相流动 自发凝结 数值模拟 边界层分离 

分 类 号：TK261[动力工程及工程热物理—动力机械及工程]