POLACH improved model establishment method suitable for large-slip working condition and measurement and calculation system

Abstract

The invention belongs to the field of railway vehicles, and discloses a POLACH improved model establishment method suitable for a large-slip working condition, and the method comprises the steps: firstly, building an initial POLACH model based on the input vehicle speed in a braking anti-slip period, the rotation speed of a vehicle wheel set, and preset wheel rail characteristic parameters; then, based on a preset working condition-friction parameter corresponding table and the initial POLACH model, a period upper limit adhesion coefficient and a period lower limit adhesion coefficient are obtained respectively; then, a conversion function reflecting the numerical fluctuation characteristic of the wheel rail adhesion coefficient in the braking antiskid period is established based on the rotating speed of the vehicle wheel set; and finally, establishing a POLACH improved model which is related to the periodic average adhesion coefficient, the periodic lower limit adhesion coefficient, the periodic upper limit adhesion coefficient and the conversion function in the braking anti-slip period and is suitable for the large-slip working condition. The invention further discloses a storage medium and a measuring and calculating system of the POLACH improved model suitable for the large-slip working condition.

Description

technical field [0001] The invention belongs to the field of rail vehicles, and in particular relates to a POLACH improved model establishment method and a measurement and calculation system suitable for large slip conditions. Background technique [0002] Adhesion is an important input parameter in the dynamics simulation of rail vehicles. According to the research results at home and abroad, there are currently seven widely used wheel-rail creep rate / force models: (1) Carter two-dimensional rolling contact theoretical model; (2) Johnson-Vermeulen theoretical model of spin-free three-dimensional rolling contact; (3) Kalker linear theoretical model; (4) Shen-Hedrick-Elkins three-dimensional nonlinear theoretical model of small spin; (5) Kalker complete theoretical model of three-dimensional rolling contact ; (6) Kalker rolling contact simplified theoretical model; (7) Polach rolling contact adhesion theoretical model. The above theoretical models, (1) and (2) are only suita...

AI Technical Summary

Problems solved by technology

In the case of large slippage, when the wheel-rail adhesion is low, braking is likely to cause a large slip on the wheel-rail contact surface and trigger the action of the anti-skid device. The periodic action of the anti-skid device makes the dissipation energy generated by the slip have a significant With a certain cleaning effect, the pollutants at the wheel-rail interface are partially removed and the adhesion is improved. That is to say, during the braking anti-skid cycle, the change of the dissipated energy generated by the dynamic friction of the wheel-rail leads to the change of the adhesion coefficient of the wheel-rail. However, the calculation of the wheel-rail adhesion coefficient in the existing Polach theoretical model is not related to the change of dissipated energy, which cannot reflect this characteristic well, leading to the instant calculation of the existing wheel-rail adhesion coefficient There are often insurmountable data biases

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