传递矩阵法分析弹性支承裂纹管道的失稳临界流速

摘要

研究两端线性弹簧支承且含有圆周非贯穿裂纹的输流管道的失稳临界流速.根据梁模型模态函数的一般表达式和裂纹处的关联式,采用传递矩阵法推导出含裂纹梁的模态函数,根据系统的特征方程具体探讨了裂纹部位、裂纹径向和周向尺寸参数对裂纹管道失稳临界流速的影响.数值仿真结果表明:由于管道裂纹的存在,系统的静态失稳和动态失稳临界流速将发生复杂的变化,管道失稳形态将随参数值的变化出现静态屈曲失稳和动态颤振失稳,并将相互转化.%The critical instability flow velocity of fluid conveying pipe,whose ends were supported by linear springs and surface contained a circumferentialpart-through crack,was investigated.The modal func-tion of the cracked pipe has been obtained by using transfer matrix method on the basis of general expres-sion of modal function and the relationship at the cracked sectionof beam.The influences of these parame-ters such as crack location,crack depth and circumferential angle of crack on critical instability flow veloc-ity were investigated on the basis of eigenequation of the piping system.The numerical results showed that system critical instability flow velocity changed complexlydue to the existing cracks on the surface of pipe and was synthetically related with crack location,crack depth and circumferential angle of crack.As a re-sult,the instability pattern may transfer from static divergence to dynamic flutter.