超临界锅炉启动汽水分离器应力分析及数值模拟

对超临界锅炉汽水分离器变工况下的应力场进行了分析计算,探讨了在高温高压条件下蠕变变形与应力间的关系,以及存在弹性变形、塑性变形和蠕变变形时应力的计算,并使用ANASYS对某超临界锅炉汽水分离器进行了数值模拟.结果表明:在结构不连续处,即汽水分离器入口附近,局部应力最大;在机组启动初始阶段,此处的应力幅很大;而在稳定运行时,此处的应力绝对值很大,但震荡幅度很小.

Stress Analysis and Simulation of a Supercritical Boiler's Starting Water Separator

The stress field in a supercritical boiler's water separator,under varying operating conditions,is calculated and analyzed.The relationship between creep and stress at high temperature is discussed together with stress calculations under the condition of coexisting elastic strain,plastic strain and creep. The water separator of a certain supercritical boiler has been numerically simulated with ANASYS.Results indicate that local stress is largest at places,where the structure gets discontinuous,i.e.in the vicinity of the separator's inlet.The stress amplitude gets very large during the first stage of starting,while during steady operation,it is the absolute value of stress that gets very large,with but very small vacillations.