Study of impact forces on wheel rim from pothole impacts and improvement of flange design to eliminate wheel bend.

Typically, an automotive passenger car wheel rim can withstand gradual loading contributed from the vehicle during cornering and high-speed maneuvering and as per the standard as well as customer requirements wheel has to withstand some impact forced contributed from radial and inclined loading. But in some cased wheel rim may not withstand the impact forces generated during impact on potholes and curbs with high-speed maneuvering. This Study helps to understand the impact on wheel rim and the forces acting on the rim flanges during pothole impact and high-speed curb impact. For Electric vehicles, always unsprung mass contributes for lesser range and the wheel rim design contributes huge for the aero drag. Due to this the wheel rim weight plays an active role for vehicle performance and dynamics. In this study author tends to explain about the design of the rim flanges considering the impact forces the wheel rims are exposed to during pothole impact. Also, In this study, road load data for a double pothole impact in electric vehicle with lightest alloy wheel rim in the segment is acquired to understand the loads acting on the rim. Based on the simulation iterations with several design changes and improvements on the flanges by increasing cross section as well as not compromising too much on the weight of the wheel rim design solution is identified. Simulation co relation for alloy wheels are not close to 100%, So the design solution is implemented for the proto part production and the same parts were tested in this double pothole impact and the wheel bend is eliminated. In wheel rims of size 19” and 20”, a reduction of 80% is there in bend is observed on the same test. Additionally, Wheel rims with 20% bend from the initial design is meeting full life when tested in rig validation. As a conclusion, Optimum design for the wheel rim flanges to meet the durability for this special pothole impact is defined and correlation factor with respect to simulation and actual validation is identified.