开式排放安全阀管系静态和动态分析方法的研究

Study on Static and Dynamic Analysis Methods for Open Drain Safety Valve Piping

对一开式排放安全阀管系实例采用等效静力法、响应谱分析法和时程分析法进行三种不同方法的静动态特性计算、分析和对比,获得安全阀管系的受力、应力和位移数据。计算结果分析表明:等效静力分析法计算的结果准确度受动载荷系数影响很大,且容易忽略非激振力作用方向所产生的一些振型,最终导致整个管系的应力计算不合理;响应谱分析法主要是基于已获得的响应谱曲线而进行的一种计算方法,在计算精度上要比等效静力法高得多,但计算结果偏于安全;时程分析法是采用时间积分的方法完整地反应出管系振动的全过程,计算精度高,但是计算量非常大。

The data on the force, stress and displacement of an open drain safety valve＇s piping was obtained by calculating, analyzing and comparing the static and dynamic properties of the safety valve piping under three different methods, namely equivalent static method, response spectrum analysis method and time-history analysis method. Analysis to the calculation results indicates that the accuracy of the result calculated by equivalent static method is greatly affected by the dynamic load factor and it is easy to overlook some vibration modes not in the direction of exciting force, finally resulting in the irrational stress calculation of the whole piping. The response spectrum analysis method is a calculation method mainly based on the already-obtained response spectrum curve, which is much better than the equivalent static method in terms of calculation precision, but inclines to be conservative in the calculation result. The time-history analysis method integrally reflects the whole process of piping vibration by time integration, which has a high calculation precision but huge calculation work.