Frequency Response Analysis Of 3-dimensional Pipes Conveying Fluid

Pipes conveying fluid are widely used in ocean engineering, aeronautics and astronautics engineering, petrochemical engineering, urban water supply and other industrial and civil fields. Each year due to the damage caused by pipeline vibration caused huge economic losses and even loss of life. Pipes conveying fluid is a very simple system with a wide variety of the dynamics of more complex engineering problems, so in recent years it has become to be a new paradigm in dynamics.In present work, wave approach is employed to investigate the vibration of different models of piping systems conveying fluid. In this paper, the inviscid fluid-dynamic forces acting on a pipe due to internal fluid flow are approximated by the plug-flow model with slender-body theory, so we get the governing equations in time domain, then by using fourier transformation we get the governing equations in frequency domain. The straight pipe elements conveying fluid are formulated using a dynamic stiffness matrix in the frequency domain. The curved pipe sections are treated with a single curved pipe element utilizing the mixed methodology of the dynamic stiffness method and the transfer matrix method.Results got by wave approach and finite element analysis software ADINA are compared, indicating that wave approach is very accurate in the frequency response analysis. Influencing factors in pipes conveying fluid are also processed.