Open Access

ARTICLE

An Improved Hierarchical ACA Technique for Sound Absorbent Materials

A. Brancati¹, M. H. Aliabadi¹, A. Milazzo²

1 Department of Aeronautics, Imperial College London, South Kensington, SW7 2AZ
2 Dipartimento di Ingegneria Civile, Ambientale e Aerospaziale, Facolta di Ingegneria, Universita degli Studi, Palermo

Computer Modeling in Engineering & Sciences 2011, 78(1), 1-24. https://doi.org/10.3970/cmes.2011.078.001

Abstract

This paper presents an improved adaptive cross approximation (ACA) approach developed in conjunction with the Hierarchical format matrix and the GMRES solver. A novel scheme to generate the cluster tree (based upon preliminary considerations of the prescribed boundary conditions) and an improved ACA algorithm (approximating the system matrix for mixed Robin conditions) are described. The asymptotic smoothness property of a kernel generated by a linear combination of two asymptotic smooth kernels is demonstrated. Numerical results show the new approach to be up to 50% faster than the conventional ACA approach.

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