Derivative-free level-set-based multi-objective topology optimization of flow channel designs using lattice Boltzmann method

A derivative-free level-set-based topology optimization method (DFLS-TO) was proposed and was used for channel structure design. Unlike in a conventional level-set method, quantum-behaved particle swarm optimization (QPSO) was used in DFLS-TO to optimize the level-set values at the knot points. The values at the non-knot points were interpolated by solving the Laplace equation. QPSO was combined with the Tchebycheff decomposition method to search for optimal level-set values in multi-objective problems. The channel boundary was represented by an iso-contour of the level-set function, and the B-spline method was used to convert the zigzag-like boundary into a smooth boundary. The lattice Boltzmann method (LBM) was integrated with the immersed boundary method to simulate the fluid flow. The Spalart-Allmaras model was incorporated with the LBM during the simulation of turbulent flows. To demonstrate the applicability of DFLS-TO, optimization of a pipe bend and a fluid distributor were performed. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

A derivative-free level-set-based topology optimization method (DFLS-TO) utilizing QPSO for optimizing level-set values and interpolating values using Laplace equation was proposed. This method efficiently searches for optimal level-set values in multi-objective problems and uses the B-spline method to convert boundaries into smooth forms. The optimization of a pipe bend and a fluid distributor was demonstrated to show the applicability of DFLS-TO.