Fluid Structure Interaction in Piping by Component Synthesis

Pipe vibrations can be induced by internal liquid pulsations which propagate throughout the piping system and create unbalanced oscillatory pressure forces at locations where either flow area or direction changes. The fluid motion is set up by a source of mechanical excitation or flow instability. Dynamic interaction of the liquid and piping may be modelled by separate analyses of liquid and solid components followed by synthesis of the component solutions. In contrast to other formulations that correctly represent interaction, the technique presented herein has the computational advantage of decomposing the anaysis into steps. The most time-consuming step is structural analysis, which may be delegated to existing, efficient computer algorithms. The synthesis method is outlined, the advantages discussed and application illustrated with numerical examples.