Title: Multi-objective optimisation of automotive drag coefficient and lift coefficient via artificial neural network and genetic algorithm
Authors: Zihou Yuan; Hongwei Zhang; Wangyang Xiang; Yanming Du; Xingren Zheng
Addresses: Hubei Key Laboratory of Digital Textile Equipment, Wuhan Textile University, Wuhan, Hubei, 430200, China ' Hubei Key Laboratory of Digital Textile Equipment, Wuhan Textile University, Wuhan, Hubei, 430200, China ' Hubei Key Laboratory of Digital Textile Equipment, Wuhan Textile University, Wuhan, Hubei, 430200, China ' Hubei Key Laboratory of Digital Textile Equipment, Wuhan Textile University, Wuhan, Hubei, 430200, China ' Hubei Key Laboratory of Digital Textile Equipment, Wuhan Textile University, Wuhan, Hubei, 430200, China
Abstract: In terms of combining traditional methods with others, group method of data handling and radial basis function neural networks have been applied to the study of automotive aerodynamics. Backpropagation neural networks have relatively few applications. The aerodynamic performance of a vehicle is improved by optimising its shape parameters. In this paper, a shape parameter optimisation method is proposed which employs backpropagation neural network model and genetic algorithm to reduce the air resistance and air lift. Five form parameters of the car are taken as design variables and 50 sets of sample data are designed using optimal Latin hypercube experimental design method. After performing CFD simulation, all the data are used for backpropagation neural network learning. Genetic algorithm is then used to perform multi-objective optimisation on all the data and the Pareto front is developed. The results show that the CD and CL of the optimised car are reduced by about 15.28% and 25.85%, respectively.
Keywords: shape parameters; computational fluid dynamics; CFD; BP neural network; NSGA-II; multi-objective optimisation; Pareto front.
Progress in Computational Fluid Dynamics, An International Journal, 2025 Vol.25 No.2, pp.79 - 94
Received: 22 Apr 2024
Accepted: 20 Jun 2024
Published online: 03 Mar 2025 *