Influence of wind angle on aerodynamic effects of a high-speed train leaving a tunnel
To study the influence of wind angle(WA)on the aerodynamic effects of the high-speed trains(HSTs)exiting tunnels,a type of HST was taken as the research object,and the tunnel aerodynamic pressure,train wind speed,flow field distribution,and train aerodynamic load were analyzed through numerical simulation.The accuracy of the numerical simulation method was verified by comparing the numerical results with those of the moving model test.The results show that the peak values of aerodynamic pressure and the maximum variation amplitude on the tunnel wall occur inside the tunnel,and the distance from the appearance location to the tunnel exit is related to WA.The leeward aerodynamic pressure is more affected by WA,and the variation amplitude decreases first,then increases and then decreases as the WA increases.Train wind speed at the tunnel exit basically increases and then decreases with the increase of WA.The train wind speed is the largest when the WA is 30°,but the moments of the train wind speed peaks that occurred at the windward and leeward sides are different.As the wind angle increases,the asymmetry of the flow field distribution increases,and the train winding characteristics from the streamlined winding gradually transition to a blunt body winding.The distance of the flow separation point increases first,then decreases and then increases again.The variation amplitudes of side force and lift increase first and then decrease as WA increases.The variation amplitudes of the side force coefficient of the head vehicle(HV)are 2.4 times and 2.6 times of those of the middle vehicle(MV)and tail vehicle(TV)respectively,and the variation amplitudes of the lift coefficient are 1.1 times and 1.5 times of those of MV and TV respectively.Therefore,ensuring the safety of the HV is the key to controlling the safety of the vehicle operation.The most unfavorable WA during the HST exiting tunnels under crosswinds is 30°,and the accident risk of the HV is the highest.
万方数据
维普
