外压圆筒临界压力的双非线性ANSYS有限元模拟与讨论

An Discussion on the Critical Pressure of External Pressure Cylinder Simulated by ANSYS’s GMNIA

利用有限元模拟软件ANSYS的几何/材料双非线性分析技术对外压圆筒临界压力进行模拟计算,将模拟结果与文献试验结果、GB 150、ASMEⅧ-2及EN 13445等压力容器设计标准中计算结果进行比较分析。结果表明:若ANSYS软件中偏差系数按外压圆筒实际最大偏差考虑,与文献中试验值和Mises公式计算结果的材料非线性修正值相比,ANSYS的模拟结果普遍偏低。模拟值按ASMEⅧ-2第5章设计系数考虑后,得到许用外压力,在弹性失稳阶段时,有的略高于ASMEⅧ-2公式法的,也有的略低于GB 150所得的。在非弹性失稳阶段,模拟所得的许用外压低于ASMEⅧ-2公式法、EN 13445规范计算结果,高于GB 150规范计算结果。

The critical pressures of external pressure cylinder were simulated by ANSYS＇s GMNIA（Geometrical and Material Nonlinear Analysis with Imperfections included）.The comparison was performed between the critical pressure values from simulation and calculated by GB 150,ASME Ⅷ-2 and EN 13445.The result show that the simulated critical pressure is lower than both of the test result in literature and the corrected result which calculated by Mises formula considering nonlinear material property.In the elastic instability stage,some allowed external pressure simulated by ANASYS using the design factor in the section 5 of ASME Ⅷ-2 are slightly higher than that from the ASME Ⅷ-2 formula method,also some slightly lower than that from GB 150.However,in non-elastic instability stage,the simulated allowed pressures are lower than that from ASME Ⅷ-2 formula method and EN 13445,and are higher than that from GB 150.