Complex fluid-filled piping systems in automotive applications undergo strong hydroacoustic excitation due to the operation of pumps and valves. The resulting pressure pulsations and fluid-structure coupling lead to structural excitation of the pipe and attached components. An efficient substructuring technique and model reduction strategies are required to optimize such piping systems with respect to the resulting structure-borne sound and undesired noise levels. The adaptation of the Craig-Bampton method to fluid-structure coupled systems turns out to be a particularly efficient model reduction technique. Break and fuel pipes are characterized by small component interfaces and repeating substructures which explains the efficiency of the used component mode synthesis. The proposed FE-based substructuring and model reduction is fully automated and allows the optimization of the dynamics of fluid-filled piping systems. An example is the computation of the optimal mounting position of the pipe resulting in a considerable reduction of the structure-borne sound induced on the target structure. In order to validate the results of the numerical simulation and to obtain a complete understanding of the fluid-structure coupled piping system, a hydraulic test bench with an innovative pulsation source is presented. The test bench allows the reliable measurement of hydoacoustic and vibroacoustic transfer functions for different pipe configurations. The observed fluid-structure interaction phenomena correspond to the numerical simulation. A considerable noise and vibration reduction is achieved by geometric means such as the variation of the clip distance (reduction of structure-borne sound up to 17 dB). An impedance boundary condition is successfully integrated in the component mode synthesis to replace large target structures by measured structural impedances.
Experimental investigation and efficient simulation methods for the vibroacoustic optimization of fluid- filled piping systems
2008
9 Seiten, 9 Bilder, 20 Quellen
Aufsatz (Konferenz)
Englisch
Dynamic Analysis of Fluid-Filled Piping System on Flexible Foundation
British Library Conference Proceedings | 2016
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