Vibration Analysis of Periodic Pipe of Fluid Conveying with Elastic Supports
Laplace transform is used to deduce the modified flow induced vibration differential equation,and therewith position related solution is expressed in a specific form.Based on Euler-Bernoulli beam theory and after elementary transformation,the transfer matrix of the fluid conveying straight pipe is obtained,furthermore the characteristic equation of the whole piping system is gained.Compared with wave approach based transfer matrix method(TMM),the proposed method provides a 2-order characteristic differential equation,which saves lots of computing time.Results of the proposed method are almost the same as those of differential transformation method(DTM)in calculating intrinsic property of fluid conveying pipe.Then,a periodic pipe is introduced to approximate the inhomogeneity of material due to the manufacture errors,critical velocity for flutter of such a pipe with elastic supports is calculated by the proposed method.It is discovered that the smaller the uneven section length of the material is,the closer the result is to the cantilever pipe.The method can be used to optimize elastic supports(including coefficients and installation position)and material properties,and can be generalized to study dynamic problems of complex structures.
vibration and wavefluid conveying straight pipetransfer matrix methodLaplace transformcritical velocity