摘要：

The purpose of this work is to evaluate a Computer Aided Engineering (CAE) method in which computational aero acoustics (CAA) techniques are used to predict the noise level from automotive fans. The engineering objective is to ensure that the noise level in an automotive cooling system or an air handling system is sufficiently low for all operating conditions. In fact, automobile manufacturers are placing increased emphasis on the reduction of cabin noise level so that this noise reduction has become a critical design consideration. This has resulted in more stringent noise requirements for air handling systems and other cooling systems. For most operating conditions, the blower is the major noise contributor for the cabin noise level. In this paper we use the extended version of the variational formulation of Lighthill's analogy, as presented in Caro et al. This formulation is ideally suited to the finite element method (FEM). It accounts for aerodynamic sources through two source terms. The first term accounts for volume sources; the second term accounts for sources defined on control surfaces, i.e., surfaces where the normal flow velocity does not vanish. An important contribution of the present work is an innovative approach for transferring information from the CFD mesh to the CAA one. This problem has a significant practical importance because CFD Contact: robert@pioneersolutionsinc.com Corresponding author: stephane.caro@fft.be Copyright c 2006 by the authors. Published by the American Institute of Aeronautics and Astronautics, Inc. with permission.

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