【摘要】 运用计算流体力学(CFD)方法对300 MW汽轮机中压缸的3种反动式改型方案的内部流场进行了数值模拟.根据计算结果分析了不同方案下的流动特性和参数变化,给出了多级效率,并分析了引起级内损失的原因.计算结果表明,反动式与冲动式两种设计方法得到的叶片效率相近;而后部加载叶型能有效抑制二次流,从而降低叶栅损失;叶片的前缘直径及弯曲角度对流场中涡结构有明显的影响.更多还原

【Abstract】 Numerical simulations of the internal flow in the mid-pressure cylinder of a 300 MW steam turbine were completed with three types of re-action cascade profiles respectively by using CFD method,which provides the basis for analyzing the effects of the different cascade profiles on the flow characteristics.The multistage efficiencies of the various designs were presented and compared.The calculation results show that the aerodynamic efficiencies of the designs based on action blade and re-action blade are close to each other;however,the aft-load blade can restrain secondary flow efficiently and thus depress the cascade loss.In addition,the diameter of the leading edge and the bowed angle of blade can influence the vortex structure in the blade-to-blade passage evidently.更多还原