# Acceleration of a Multi-Objective Topology Optimisation in 2D Electro-Magnetic Field Based on the Level-Set Method and the Boundary Element Method by the-H Matrix Method

Acceleration of a Multi-Objective Topology Optimisation in 2D Electro-Magnetic Field Based on the Level-Set Method and the Boundary Element Method by the-H Matrix Method

K. Nakamoto H. Isakari T. Takahashi T. Matsumoto

Nagoya University, Japan

Page:
686-695
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DOI:
https://doi.org/10.2495/CMEM-V5-N5-686-695
N/A
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Accepted:
N/A
| | Citation

OPEN ACCESS

Abstract:

In this study, we develop an efficient topology optimisation method with the - matrix method and the boundary element method (BEM). In sensitivity analyses of topology optimisation, we need to solve a set of two algebraic equations whose coefficient matrices are common, particularly in many cases. For such cases, by using a direct solver such as LU decomposition to factorise the coefficient matrix, we can reduce the computational time for the sensitivity analysis. A coefficient matrix derived by the BEM is, however, fully populated, which causes high numerical costs for the LU decomposition. In this research, the LU decomposition is accelerated by using the -matrix method for the sensitivity analyses of topology optimisation problems. We demonstrate the efficiency of the proposed method by a numerical example of a multi-objective optimisation problem for 2D electromagnetic field.

Keywords:

boundary element method, H-matrix method, level-set method, topological sensitivity, topology optimisation

References

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