The Study On Simulation Method Of Curve Negotiation On Roller Rig

Curve tracks have always been the weak link of railway: On the one hand,the wear of wheel flange and rail are serious,which increases the risk of train derailment;on the other hand,the mechanism of curve passing is very complex.Therefore,the curve passing performance of railway vehicles has always been the focus and difficulty of research.As an important means to study the dynamic performance of railway vehicles,the simulation of curve passing performance has not been perfected so far.Aiming the simulation method of curve passing on roller rig,the following researches have been carried out:Firstly,the geometric theories of track curve are studied.Spatial curves of widened gauge and superelevation are given,Furthermore,according to the selected curve lines,the time control curves for simulating superelevation and the length difference between internal and external rails are given.Secondly,the simulation scheme of curve negotiation on roller rig is studied.The movement of rollers on vertical and horizontal planes is analyzed,and the simulation method of curvature is analyzed in detail: The trajectory of the guide wheel is mapped to the lateral movement and tangent angles in the geometric characteristics of the curve.By means of large stroke actuator,the guide wheel moves in the guide groove of a specific shape,so that the rail wheel unit not only realizes the lateral movement in the Y direction,but also continuously deflects to the tangent angle of the corresponding line,thus dynamically simulating the curvature of the curve line,With the simulation of superelevation and length difference between inner and outer rails,the track wheel can reproduce the geometric shape and position characteristics of the track,and the centrifugal effect of the tested vehicle is expected.Aiming at the need of a roller rig under construction,the trajectory of the guide wheel and the geometric shape of the transverse guide groove are calculated by MATLAB software.Then,the simulation scheme of track irregularity is analyzed.The track spectrum parameters recommended in the paper "Study on General Track Spectrum for Chinese Main Railway Lines" are selected.The track spectrum is transformed into a space domain sample varying with mileage by using triangular series method,and the track quality index(TQI)of the sample is evaluated.According to the standard TQI management value,the speed grade coefficient is used to correct it,so that it is more in line with the actual situation of railway lines in China and can be used for test bench.Finally,the simulation analysis of the bench simulation is carried out.The SIMPACK model of line and bench test is established to simulate the dynamic behavior of 4 axles vehicle passing through straight line-transition curve-circular curve-transition curve-straight line.Compared with the difference of dynamic performance,it is concluded that the curve simulation method studied in this paper has practical value.