Abstract: Wheelset rolling radius difference (RRD) is taken as the design objective, a numerical optimal design model for railway vehicle wheel profile is built on the basis of the cubic spline theory. The cubic spline is used to efficiently smooth the wheel profile, and RRD determines the vehicle dynamics performance. As an example, to improve curving ability of LMA wheelset, the present model is used to improve the wheelset rolling radius difference, which mainly optimizes the flange root region of the LMA wheel profile. The rolling contact and dynamic behavior of the improved wheel profile are analyzed in detail. The results show that, in comparison with the LMA profile, though contact pressure and stress increase in the flange root region of the wheel, the improved wheel profile significantly improves the vehicle curving performance, other indices such as vehicle critical speed, performance, and safety index are basically unchanged. The optimization of LMA wheel profile reaches the expected goal. The example demonstrates the effectiveness and the feasibility of the proposed model based on the wheelset rolling radius difference control.

Key words: Vehicle dynamics, Curving behavior, Numerical optimization, Wheel profile design, Wheelset rolling radius difference