Performance of Several Viscothermal Acoustic Finite Elements

A finite element model of perforated panel absorbers including viscothermal effects

“…The present finite element implementation corresponds to an existing method [23] with a differently scaled energy equation that results in an unsymmetrical system matrix, but is reported here for completeness. A finite element model that implements a boundary value problem for Eqs.…”

A Two-Dimensional Acoustic Tangential Derivative Boundary Element Method Including Viscous and Thermal Losses

“…FEM implementations for arbitrary geometries rely on a direct evaluation of the full linearized Navier-Stokes equations. This was initially proposed by Bossart et al, 1 realized by Malinen et al 2 and later presented in different variations by Cheng et al, 3 Joly et al 4 and Kampinga et al 5 FEM can be computationally demanding, since the loss mechanisms require proper meshing of the associated boundary layers. Further, temperature and velocity are added as extra degrees of freedom.…”

Viscothermal accoustics using finite elements

“…e velocity shape functions are quadratic with added bubble functions. e convergence of the viscothermal acoustic Crouzeix-Raviart-like triangular finite element (with quadratic temperature shape functions) is also evaluated in [43]. e convergence is comparable to the Taylor-Hood-like elements in the studied case.…”

“…e results confirm the theory and make it more concrete. e paper [43] contains additional validation tests and is reproduced in appendix B.…”

“…e convergence rates of several viscothermal acoustic finite elements with velocity and pressure shape function pairs that satisfy the inf-sup condition are studied in [43] on a 2- thin gap problem. Good convergence rates are obtained with these elements.…”