Influence of Wheelset Installation Deflection Angle on Dynamic Characteristics of High-Speed Vehicles Crossing Switch

The initial deflection angle of high-speed trains caused by inaccurate positioning sharply can aggravate wheel-rail contact relationships and affect traffic safety, especially when passing through weak areas such as turnouts. In order to study the dynamic performance of vehicles passing through high-speed turnouts at initial installation deflection angle, a vehicle-turnout coupling dynamic model with initial deflection angle was established with No.18 turnouts as the research object. Four working conditions, namely front wheel pair deflection, rear wheel pair deflection, front and rear wheel pair deflection in the same direction and front and rear wheel pair deflection in the opposite direction, were simulated. The effects of different deflection angles on the vehicle's fork entry posture and straight and reverse crossing performance were analyzed by combining theoretical derivation and numerical simulation. The results indicate that the initial deflection angle deflecting to switch rail will cause the advance of wheel-rail transition position, and even the rim contact will be caused. The influence of initial installation deflection angle on wheel-rail vertical force is mainly related to deflection form and deflection angle. When the deflection angle exceeds a certain limit, the inherent irregularity in turnout area further aggravates vertical wheel-rail impact. The wheel-rail transverse force is mainly controlled by the superposition of the main contact point direction and the transverse impact direction of the turnout area. When the front and rear wheelsets deflect reversely, the wheel-rail contact relationship deteriorates. When the deflection angle is from −2.0 to −3.0 mrad, the derailment coefficient exceeds the limit, which affects the driving safety.