Research On Optimization Of Straddle-type Monorail Train's Running Surface

With the straddle monorail train promoted in China,the problem of the partial wear of the running wheels is increasingly prominent.Tire adhesion performance drops sharply due to tire wear,the monorail train are having a detrimental effects such as curve pass performance degradation,low drive efficiency,and low braking efficiency.The uneven wear of the running wheels causes a series of problems such as safety,energy consumption and pollution of the monorail train.Therefore,studying the wear mechanism of the running wheel and uneven wear control method of the monorail train has important theoretical significance and engineering application value.The running mechanism of the straddle monorail is different from that of the automobile and the railway vehicle.The friction characteristics and wear characteristics of the running tire are also different.To describe more accurately of the friction and wear characteristics of running wheel and running surface,a wheel-rail friction model and a wheel-rail wear model for straddle monorail trains are proposed.Friction and wear tests of tread rubber were carried out with a friction and wear testing machine.The variation of friction coefficient and wear of tread rubber with normal pressure,slip velocity and temperature was studied.In order to analyze the wheel-rail interaction of the running wheel,the ADAMS is used to establish the dynamic model of the straddle-type monorail train.Simulate and analyze the radial force,lateral force,positive torque,side angle and roll angle of the eight running wheels in the front and rear bogies.The reasons for the uneven wear at the shoulder of the running wheel under the curve condition are analyzed.In order to explore the control method of uneven wear of running wheels,the wear characteristics of running wheels under the action of sideslip angle and roll angle were compared and analyzed.Establishing different types of running surfaces and analyzing the influence of running surface types on wear characteristics of running wheels.The running surface are evenly divided to obtain a plurality of type points,the NURBS curve is used to reconstruct the cross-section curve of the running surface.A description method of running surface is established by evenly dividing the running surface into several points.A multi-objective optimization model for running surface optimization design is established by combining the construction of neural network with multiobjective genetic algorithm.The optimized "running surface" is obtained to achieve the goal of reducing the uneven wear of running wheel tires.