The purpose of this paper is to study the equipment parameters of expressway convective wind energy collection devices and determine the optimal structural parameters by numerical methods. Firstly, the characteristics of convection wind energy and flow field on the expressway are analyzed and the principle of wind energy utilization is determined. Based on traditional resistance wind turbines, two different blades of the device are designed and developed. Some structural parameters (such as blade height and the number of blades) of the device are discussed based on the flow field characteristics. Secondly, the device is numerically simulated using Star CCM + software, and the optimal structural parameters are determined based on the power coefficient. Thirdly, the proposed numerical analysis method is verified and indirect verification is used to determine the most suitable turbulence model and grid independence based on the similarity principle. Based on the above research results, the experimental verification is used to determine the high reliability of the simulation model. Finally, the simulation results between the Rectangular turbine and the Savonius turbine are compared and obtained. The results show that the device is useful for the wind energy usage, wind energy conversion and the wind resistance reduction of the opposite vehicle. At the same time, when the inlet wind speed is 15 m/s, the tip speed ratio (TSR) is 1.4, the device is rectangular turbine (RT), the height of blade is 1.55 m, the number of blades is 4, and the maximum power coefficient C-p is 0.363.