Point collocation scheme in silencers with temperature gradient and mean flow

JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS

卷:291

Article

Denia, F. D.¹  Sanchez-Orgaz, E. M.¹  Baeza, L.¹  Kirby, R.² 

[1] Univ Politecn Valencia, Ctr Invest Tecnol Vehiculos, E-46022 Valencia, Spain

[2] Brunel Univ, Coll Engn Design & Phys Sci, Mech Engn, Uxbridge UB8 3PH, Middx, England

关键词: Dissipative silencer;    Temperature gradient;    Mean flow;    Point collocation;   

DOI  :  10.1016/j.cam.2015.02.007

来源: Elsevier

【 摘 要 】

This work presents a mathematical approach based on the point collocation technique to compute the transmission loss of perforated dissipative silencers with transversal temperature gradients and mean flow. Three-dimensional wave propagation is considered in silencer geometries with arbitrary, but axially uniform, cross section. To reduce the computational requirements of a full multidimensional finite element calculation, a method is developed combining axial and transversal solutions of the wave equation. First, the finite element method is employed in a two-dimensional problem to extract the eigenvalues and associated eigenvectors for the silencer cross section. Mean flow as well as transversal temperature gradients and the corresponding thermal-induced material heterogeneities are included in the model. In addition, an axially uniform temperature field is taken into account, its value being the inlet/outlet average. A point collocation technique is then used to match the acoustic fields (pressure and axial acoustic velocity) at the geometric discontinuities between the silencer chamber and the inlet and outlet pipes. Transmission loss predictions are compared favorably with a general three-dimensional finite element approach, offering a reduction in the computational effort. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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