超超临界汽轮机调节级叶片汽流弯应力数值计算

Numerical analysis on steam bending stress on control stage blade of an ultra supercritical unit steam turbine

对某超超临界机组汽轮机配进汽室的调节级进行三维全周定常数值模拟,提取动叶壁面各个节点的静压力,编写插值程序将动叶壁面静压力通过逐点插值的方式施加于叶片有限元模型中,计算调节级在调节阀4阀和1阀全开2种工况下的叶片汽流弯应力。结果表明:2种工况下动叶壁面的最大静压力分别为22.64、17.76MPa,位于叶片进汽边,静叶壁面的最大静压力分别为23.93、23.95MPa;1阀全开工况的最大汽流弯应力约为4阀全开工况的10倍。

Accurate calculation of steam bending stress on control stage blade has important guiding significance to development of efficient and reliable control stage blades.Numerical simulation on 3Dsteady flow of a control stage blade with admission chamber in an ultra supercritical unit steam turbine was conducted,and the node steam force on the surface was extracted.Furthermore,interpolation procedures were compiled to transform the node steam force to the node force applied in the blade finite element model,and the steam bending stresses under conditions of 4valves open and 1valve open were calculated.The results show that,the maximum static pressure on the rotor blade surface under the above two conditions was 22.65 MPa and 17.76 MPa,respectively;the maximum static pressure on the stationary blade surface was 23.93 MPa and 23.95 MPa,respectively;the maximum steam bending stress under 1valve open condition was about 10 times larger than that under the 4valves open condition.