Simulation of Vibro-Acoustics in Flexible Piping Systems

Abstract

Pump suctuation and valve action in piping systems can lead to undesired excitation of structural components by propagating sound waves in the suid path. This vibro–acoustic problem is addressed by studying the dynamics as well as excitation mechanism. It is found that internal suid sow does neither alter operational desections nor vibrational modes considerably for low Mach numbers as encountered in most piping systems conveying heavy suids. Therefore, the suid is modelled at rest to solve the vibro–acoustic problem. On the other hand suid–structure interaction has a significant insuence and cannot be neglected. Pipe models are generated in three dimensions by using Finite Elements. The acoustic wave equation in the suid is hereby fully coupled to the structural domain at the suid-structure interface. These models are used for simulating mode excitation by transient simulation and modal analysis. Reduced component models allow for efficient simulations. The model reduction is hereby based on a modal truncation. Afterwards, dominant modes are selected based on controllability and observability considerations. Modal controllabilities are furthermore used to quantify the excitation of vibrational modes by white noise at the pipe inlet. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)