Abstract: In order to study the influence of the strong wind and rainfall environment on the aerodynamic performance of the high-speed train, the Lagrangian discrete phase model is used to simulate the movement of the raindrop in the air. The interaction between the air and raindrop is considered, and the phase-to-phase coupling method is used to simulate the strong wind and rainfall environment. Through performing the aerodynamic calculation of a high-speed train under strong wind and the raindrop landing calculation due to the gravity force, the accuracy of the computational model is verified. On this basis, the wind-rain two phase flow computation of the high-speed train under different yaw angles and rainfall intensities is carried out, and the flow field characteristics and aerodynamic characteristics of high-speed trains under strong wind and rainfall environment are studied. Computational results show that, for the same yaw angle, with the increase of the rainfall intensity, the positive pressure on the windward of the head car increases, and the negative pressure on the leeward of the head car increases due to the impact of the raindrops, leading to the deterioration of the lateral aerodynamic performance of the train. Under strong wind and rain conditions, the aerodynamic load coefficients increase with the increase of the yaw angle and rainfall intensity, and follow a linear relationship with the rainfall intensity. For the same yaw angle, the increased percent of the aerodynamic load coefficient increases with the increase of the rainfall intensity. For the same rainfall intensity, the increased percent of the aerodynamic load coefficient decreases with the increase of the yaw angle. The aerodynamic load coefficient of the train can be approximated as a quadratic polynomial with respect to the yaw angle and rainfall intensity, and the squared term of the rainfall intensity can be ignored.

Key words: high-speed train, rainfall intensity, aerodynamic performance, discrete phase, yaw angle