球形容器接管外拐角表面裂纹疲劳扩展计算机模拟技术

A Computer Simulating Technique of Fatigue Growth of Surface Defect at Nozzle Out-corner of Spherical Vessel

文通过实物容器实验对接管外拐角表面裂纹疲劳扩展形状作了分析，并用数值方法对该裂纹作了模拟跟踪，将实验和计算所得外拐角表面裂纹同无限大平板半椭圆、接管内拐角表面裂纹作了比较，并指出了接管外拐角表面裂纹的扩展不仅趋于曲线形状，而且裂纹扩展呈现凸出现象；并指出，常规的假定无限大平板上裂纹形状运用到接管外拐角所产生误差的缘由。

On the basis of real vessel experiment, the fatigue shape growth of surface crack at nozzle out-corner has been analyed. The numerical simulating method has been used to fellow it. The results of surface fatigue crack at out-corner obtained from experiment and computation have been compared to the semi-elliptical surface cracks on infinite plate and the surface crack at the in-corner. The result indicates that the surface crack growth at out-corner not only tends to a curved shape, but also presents a protruding phenomenon. Besides, the sources of errors are explained when using the postulation of crack shape of infinite plate to the nozzle out-corner