6533b7cefe1ef96bd1256edb

RESEARCH PRODUCT

A Domain Imbedding Method with Distributed Lagrange Multipliers for Acoustic Scattering Problems

Tuomo RossiJari ToivanenErkki Heikkola

subject

symbols.namesakeConstraint algorithmHelmholtz equationDiscretizationPreconditionerLagrange multiplierDirichlet boundary conditionMathematical analysissymbolsBoundary value problemFinite element methodMathematics

description

The numerical computation of acoustic scattering by bounded twodimensional obstacles is considered. A domain imbedding method with Lagrange multipliers is introduced for the solution of the Helmholtz equation with a second-order absorbing boundary condition. Distributed Lagrange multipliers are used to enforce the Dirichlet boundary condition on the scatterer. The saddle-point problem arising from the conforming finite element discretization is iteratively solved by the GMRES method with a block triangular preconditioner. Numerical experiments are performed with a disc and a semi-open cavity as scatterers.

yearjournalcountryeditionlanguage
2003-01-01
https://doi.org/10.1007/978-3-642-55856-6_40