Lateral Vibration of a Pipe Conveying a Fluid

The lateral vibration of a pipe conveying a fluid is investigated theoretically and experimentally. An exact solution for the natural frequency, axial distribution of phase and modal envelope is computed for a pinned-pinned, fixed-fixed and pinned-fixed span. Approximate one and two term Galerkin, Rayleigh-Ritz and Fourier series solutions are obtained and compared with the exact solution. It is found that a two term Galerkin or Rayleigh-Ritz solution is simple to evaluate and provides a good estimate of frequency and phase. The influence of axial tension and internal pressure is included.The experimental results are in agreement with theory at low flow speeds but show the difficulty of accurate buckling flow speed prediction.