Optimisation study of aerodynamic drag based on flow field topology in box-type trucks

The research objective of this study is to solve the problem of excessive air resistance of box trucks at high speed.Taking the small box-type truck model as the object of study, the simulations were done with CFD software to simulate the external flow field of the small box-type truck driving at high speed.Under the premise of ensuring driving safety, the area at the front of the truck and the top of the carriage is identified as the area to be optimised.The local optimum criteria are used to topologise the local external flow field to be optimised, and the model is remodelled according to the optimisation results.Validation showed that a suitable optimisation scheme could be proposed by using the local optimum criteria.The design method provided in this scheme can provide a better scheme for the research of truck drag reduction, improve design efficiency and save optimisation time.