On stability of a clamped-pinned pipe conveying fluid

Abstract

In the past, stability of an undamped clamped-pinned pipe conveying fluid has been always considered numerically leading to controversial results. Païdoussis (2004) has shown that a numerical stability analysis of a clamped-pinned pipe requires exceptionally large number of vibration modes to obtain the correct dynamical behaviour. In this paper, analytical proof of stability of a clamped-pinned pipe conveying fluid at a low speed is given. A tensioned Euler-Bernoulli beam in combination with a plug flow model is used as a model. The stability is studied employing a D-decomposition method. Advantages and disadvantages of this method with respect to the conventional methods are discussed. For demonstration of the method’s capabilities, it is applied to a clamped-pinned pipe subject to linearised Morison damping caused by the surrounding fluid. Key words: pipe conveying fluid, stability, D-decomposition method 1