6533b85dfe1ef96bd12bdd48

RESEARCH PRODUCT

Time-harmonic solution for acousto-elastic interaction with controllability and spectral elements

Sanna Mönkölä

subject

ControllabilityDiscretizationSpectral element methodfluid-structure interactionspectral element methodacoustic wavescoupled problemTime-harmonic solutioncontrollabilityConjugate gradient methodFluid-structure interactionTime domainCoupled problemMathematicsElastic wavesSpectral element methodelastic wavestime-harmonic solutionApplied MathematicsMathematical analysisLinear systemFinite differenceFinite element methodControllabilityComputational MathematicsAcoustic wavesConjugate gradient algorithmconjugate gradient algorithm

description

The classical way of solving the time-harmonic linear acousto-elastic wave problem is to discretize the equations with finite elements or finite differences. This approach leads to large-scale indefinite complex-valued linear systems. For these kinds of systems, it is difficult to construct efficient iterative solution methods. That is why we use an alternative approach and solve the time-harmonic problem by controlling the solution of the corresponding time dependent wave equation. In this paper, we use an unsymmetric formulation, where fluid-structure interaction is modeled as a coupling between pressure and displacement. The coupled problem is discretized in space domain with spectral elements and in time domain with central finite differences. After discretization, exact controllability problem is reformulated as a least-squares problem, which is solved by the conjugate gradient method. peerReviewed

https://doi.org/10.1016/j.cam.2009.08.040