Frequency-domain Transfer Matrix Method of 14 Equations Model for Fluid-structure Interaction in Pipes

Based on the theory of beam model,a 14-equations model of fluid-structure interaction was set up,the volume force and lateral inertia of fluid was taken into account,but the friction between fluid and pipe was neglected.The time-domain model was transformed into frequency domain by Laplace transformation,and 12 fourth order ordinary differential equations and 2 second order ordinary differential equations was deduced.The equations can be solved directly to get the analytical solution in frequency domain of simple straight pipe.By the relation of the numerical results between the beginning and the end of the pipe,and combing with the boundary conditions,a transfer matrix of pipe system was gained.In the end,simulation was carried out,and the numerical results were verified by experimental ones.