导流环结构对汽轮机高压排汽缸气动性能的影响

摘要

A numerical simulation on full 3D steady viscous flow fields in the HP exhaust hood of steam turbines is conducted by using the commercial computational flow dynamics software CFX. The result shows that the relative axial length of transition section in diffuser, relative height of the guiding annulus and radius of the guiding annulus of diversion section have great effects on aero-dynamic performance of the HP exhaust hood. The total pressure loss coefficient of the exhaust hood decreases gradually when the relative axial length of transition section in diffuser and radius of the diversion section of guiding annulus increase. To improve the total pressure loss coefficient of the exhaust, the relative height of the guiding annulus and radius of the guiding annulus of diffuser area exists an optimum.%文章采用商用计算流体动力学软件CFX,对不同导流环结构汽轮机的高压排汽缸进行了全三维粘性定常流动数值模拟,结果表明,扩压器过渡段相对轴向长度、导流环相对高度以及导流段处导流环半径对高压排汽缸气动性能均有重要影响。随扩压器过渡段相对轴向长度以及导流段导流环半径的增加,排汽缸总压损失系数逐渐降低；导流环的相对高度以及扩压段处导流环的半径则存在有最佳值,使得排汽缸总压损失系数最小。