دورية أكاديمية

Topological sensitivity analysis revisited for time-harmonic wave scattering problems. Part I: the free space case.

التفاصيل البيبلوغرافية
العنوان: Topological sensitivity analysis revisited for time-harmonic wave scattering problems. Part I: the free space case.
المؤلفون: Le Louër, Frédérique1 (AUTHOR) frederique.le-louer@utc.fr, Rapún, María-Luisa2 (AUTHOR) marialuisa.rapun@upm.es
المصدر: Engineering Computations. 2022, Vol. 39 Issue 1, p232-271. 40p.
مصطلحات موضوعية: *SCATTERING (Physics), *ACOUSTIC wave propagation, *SINGULAR perturbations, *SENSITIVITY analysis, *ASYMPTOTIC expansions, *ADJOINT differential equations, *PHONONIC crystals
مستخلص: Purpose: In this paper, the authors revisit the computation of closed-form expressions of the topological indicator function for a one step imaging algorithm of two- and three-dimensional sound-soft (Dirichlet condition), sound-hard (Neumann condition) and isotropic inclusions (transmission conditions) in the free space. Design/methodology/approach: From the addition theorem for translated harmonics, explicit expressions of the scattered waves by infinitesimal circular (and spherical) holes subject to an incident plane wave or a compactly supported distribution of point sources are available. Then the authors derive the first-order term in the asymptotic expansion of the Dirichlet and Neumann traces and their surface derivatives on the boundary of the singular medium perturbation. Findings: As the shape gradient of shape functionals are expressed in terms of boundary integrals involving the boundary traces of the state and the associated adjoint field, then the topological gradient formulae follow readily. Originality/value: The authors exhibit singular perturbation asymptotics that can be reused in the derivation of the topological gradient function that generates initial guesses in the iterated numerical solution of any shape optimization problem or imaging problems relying on time-harmonic acoustic wave propagation. [ABSTRACT FROM AUTHOR]
قاعدة البيانات: Academic Search Index
الوصف
تدمد:02644401
DOI:10.1108/EC-06-2021-0327