Optimization of unsteady jet control flow method for aerodynamic drag reduction of heavy truck model
Thanh-Long Phan, Tien Thua Nguyen, Thi Huyen Nguyen
Abstract
The aerodynamic drag reduction of ground vehicles is crucial for meeting the increasingly strict emission standards. In this context, a potential approach to achieve this objective is to use active flow control techniques. Many active flow control techniques have been applied for ground vehicles, and the unsteady jet device has been proven to have better control energy efficiency than some other flow actuators. Therefore, this study focuses on applying this unsteady jet technique to a realistic truck model. The main parameters of the control flow device, including jet amplitude, jet angle, and control frequency were optimized to reduce the aerodynamic drag of the truck model and achieve the maximum control energy efficiency. Numerical studies were performed based on the CFD method with the k-ω SST turbulence model. A 25-level optimal Latin Hypercube design experimental study was conducted. The optimization method based on the Kriging response surface model and genetic algorithm was chosen to determine the optimal solution. The results show that the maximum energy efficiency is 9.174 % using the unsteady jet devices with the optimal parameters on the small-scale truck model. • Application of unsteady jet method to reduce the aerodynamic drag for a realistic truck model. • The aerodynamic characteristics of the truck model are analyzed and compared with experimental results. • Optimal operation parameters of the unsteady jet device are determined by using the Kriging model and Genetic algorithm method. • The application of optimized unsteady jet reduces the size of large vortex and backflows in the wake region of truck model.