核电汽轮机高压缸三维有限元热应力分析

3-Dimensional Finite Element Analysis of a Nuclear Steam Turbine 's H. P. Casing

在变工况时，核电汽轮机的汽缸表面温度随蒸汽温度快速变化，引起汽缸内部大的温差与热应力；在稳态条件下，汽缸大压差截面处也存在大的温差与热应力．文中着重介绍核电汽轮机高压缸的热应力计算和分析，考虑了中分面的密封分析，计算了冷态起动、加负荷、稳态和甩负荷过程中的瞬态非线性温度场，然后以材料非线性模式求解相应的热应力场。

Abstract Under transient operating conditions, the temperature of a nuclear steamturbine casing's inner surface rapidly changes with the pressure inside the casing,causing appreciable temperature differences and thermal stresses to appearin the casing j and even under steady operating conditions do considerabletemperature differences and thermal stresses exist, where pressure differencesare large across blade carriers.The paper primarily explains the method usedin calculating and analyzing thermal stresses in H.P. casings of nuclear steamturbines, accompanied by a check on the sealing capability of its flanges. Calculation subjects include nonlinear transient temperature fields during coldstarts, loading, steady operation and load rejection; followed by calculationsof the corresponding thermal stress fields with a88umed nonlinear materialproperties.