Numerical Study of Post-Buckling of Clamped-Pinned Pipe Carrying Fluid Under Different Parameters

This research aims to calculate the first three natural frequencies and critical velocity of a fluid-conveying pipe are obtained with numerical approach with standard finite element method and this by discretizing the structure wall and internal flow, starting from beam type with two degrees of freedom per node. The determination is done to the vibrational equation from the fluid-structure coupling using Lagrange energy principle. Parameters frequencies are calculated by using a program developed on MATLAB. The advantage of MATLAB language by using standard functions is to present the first Eigen-modes of the system aspect interaction fluid-structure for different physic and geometric parameters in complex planes. The results are converged and compared with those predicted by semi-analytic method. Numerical results show the effect of mass ratio, length and elastic foundation on stability region and static instability and static instability range.