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FE Analysis of a Partially Trimmed Vehicle using Poroelastic Finite Elements Based on Biot's Theory
ISSN: 0148-7191, e-ISSN: 2688-3627
Published May 15, 2007 by SAE International in United States
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A poroelastic material can be represented as a material that is constituted by two phases: a structural phase given by a solid frame, and a fluid phase given by the air that fills the pores of the solid frame itself. In the mid frequency range, the physical behavior of both phases and their interactions need to be properly modeled in order to predict accurately the dynamic behavior of the porous material. This can be done using finite elements based on Biot's theory, which describes the macroscopic behavior of poroelastic materials by characterizing them through a set of parameters directly measured on material samples.
In this paper, numerical/experimental correlations obtained using two commercial software programs that implement libraries of poroelastic materials are presented.
A free-free steel plate covered by a 20mm thick layer of foam and a massive heavy layer has been selected as a first test case. The plate was excited with an electrodynamic shaker and velocities on the heavy layer top surface were measured by means of a laser vibrometer. Velocities on the steel side were also measured by means of standard accelerometers. The experimental results were then compared to those obtained with FE models, showing an acceptable degree of correlation.
After this first validation phase, the much more complex problem of the simulation of a trimmed Body In White (BIW) was tackled. In doing this, two different modeling strategies for the assembly of the BIW and of the insulation components available in the commercial FE software programs used for the simulations were assessed. Also in the case of the trimmed BIW, the results obtained were more than satisfactory.
CitationBertolini, C., Gaudino, C., Caprioli, D., Misaji, K. et al., "FE Analysis of a Partially Trimmed Vehicle using Poroelastic Finite Elements Based on Biot's Theory," SAE Technical Paper 2007-01-2330, 2007, https://doi.org/10.4271/2007-01-2330.
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