Joint Research on Aerodynamic Characteristics and Handling Stability of Racing Car under Different Body Attitudes

Abstract

With the rapid development of FSAE, the speed of racing cars has increased year by year. As the main research content of racing cars, aerodynamics has received extensive attention from foreign teams. For racing cars, the aerodynamic force on the aerodynamic device ultimately acts on the tires through the transmission of the body and the suspension. When the wheel is subjected to the vertical load generated by the aerodynamic device, the ultimate adhesion capacity of the wheel is improved. Under changing conditions, racing wheels can withstand greater lateral and tangential forces. Therefore, the effects of aerodynamics have a more significant impact on handling stability. The FSAE racing car of Jilin University was taken as the research object, and this paper combines the wind tunnel test, the numerical simulation and the dynamics simulation of the racing system. The closed-loop design process of the aerodynamics of the FSAE racing car was established, and the joint study of aerodynamic characteristics and handling stability of racing car under different body attitudes was realized. Meanwhile, the FSAE car was made the modification of aerodynamic parameter on the basis of handling stability. The results show that, after the modification of the aerodynamic parameters, the critical speed of the car when cornering is increased, the maneuverability of the car is improved, the horoscope test time is reduced by 0.525 s, the downforce of the car is increased by 11.39%, the drag is reduced by 2.85% and the lift-to-drag ratio is increased by 14.70%. Moreover, the pitching moment is reduced by 82.34%, and the aerodynamic characteristics and aerodynamic efficiency of the racing car are obviously improved. On the basis of not changing the shape of the body and the aerodynamic kit, the car is put forward to shorten the running time of the car and improve the comprehensive performance of the car, so as to improve the performance of the car in the race.

Double Optimization Design of the Formula Racing Car Frame Based on the Variable Density Method and the Joint Variable Method

“…(3) Constraints: 1 Because the maximum stress of the frame under three typical working conditions is 114.6 MPa, which is lower than the allowable stress and has a large optimization space, the maximum stress is set to not exceed 200 MPa. 2 Respectively constrain the displacement to not exceed the original value under various working conditions; for example, the displacement does not exceed 0.3792 mm under bending conditions; (4) Set objective function: With the overall goal of minimizing the net weight of the vehicle frame, use the accuracy and output card provided in Hypermesh to define the accompanying variables and output sensitivity analysis results.…”

“…It draws participation from countless college students worldwide every year. To date, hundreds of schools have enthusiastically taken part in this competition [1][2][3].…”

“…The optimization results will retain the material in the area with higher unit density to obtain the trend of the whole vehicle pipe fittings, so that the designed frame structure is more accurate and the anti-deformation performance will be better. (2) The sensitivity analysis is introduced into the field of racing frames. The adjoint variable method is used to analyze the sensitivity of the frame, and the influence factors of each variable are obtained according to the results.…”

The influence of vehicle body roll motion on aerodynamic characteristics under crosswind condition

“…The thickness of the first layer in the mesh was set to 0.1 mm, and the maximum y+ value was 60, as demonstrated in Figure 5. Based on empirical values, the mesh scheme was deemed suitable for meeting the simulation requirements (Zhang et al , 2022).…”