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This work aims to present a method to predict the acoustic properties of flexible polyurethane foams from the numerical results of a macroscopic simulation of the foaming process. The foaming process simulation is carried out using a meshless method and a set of models taking into account the main chemical reactions, the exothermic effect as well as the thermo-rheo-kinetic coupling. To predict the acoustic properties of the foam, a semi-phenomenological model is used to avoid the experimental characterization of the foam microstructure. The distribution of the non-acoustical parameters involved in the Johnson-Champoux-Allard model were determined using the proposed method for a square panel mold. These results are used to calculate the normal-incidence sound absorption coefficient, which is compared to experimental and numerical results presented in the literature. The predicted acoustic behavior of the polyurethane foam is in good agreement with results in previous works. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new simplified method called “Pseudo Inverse Approach” (PIA) for the axi-symmetrical cold forging modeling. The PIA keeps the advantages of the Inverse Approach (very fast) but gives good stress estimation by taking into account the loading history. Some intermediate configurations are created by using a free surface method to consider the deformation paths without contact treatment. A new direct algorithm of plasticity is developed leading to a fast and robust plastic integration procedure for very large strain increments. The PIA results are compared to those obtained by using ABAQUS software to show the efficiency and limitations of the PIA. [Copyright &y& Elsevier]