Experimental And Simulative Research On Thermoelectric Characteristics Of Pantograph Friction Pair Under Rain Condition

The temperature rise characteristics of the friction pairs of the pantograph catenary system directly affect the properties of contact materials and accelerate the wear of contact surfaces,the current density distribution of the contact surface reflects the quality of the current receiving.In order to study the distribution characteristics of temperature and current density of the contact surface of the friction pair,the electrical contact experiment of pantograph catenary was carried out under the three conditions of normal,light rain and heavy rain using the self-developed device of the research group,and established a finite element simulation model and proved its validity by the experimental temperature,and then analyzed and compared the distribution of current density on the contact surface,and carried out the simulation under the condition of high speed and large current and analyzed the variation of temperature distribution characteristics of the contact surface.The results show that the current density and temperature increase with the increase of current,when contact pressure increases in normal environment,the contact surface temperature increases while the current density increases first and then decreases.With the increase of the sliding velocity,the current density and temperature gradually decrease.In rain conditions,the temperature and the current receiving quality of the contact surface are lower than those in normal environment,when pressure increases the contact surface temperature increases gradually while the current density of contact surface decreases first and then increases,and with the increase of the sliding speed,the current density and temperature increase first and then decrease.The maximum value of tail temperature difference appears at both ends of the slider,the temperature gradient near the middle part is small while the peak distance is larger;in the rain environment,the tail temperature difference is smaller than that in normal environment and change small with time and rainfall,in the rain environment the peak distance is smaller than that in normal environment,the peak distance of the central part of slider has a decrease trend with time,but has an increasing trend at both ends of the slider.In the initial stage,the rainfall has a greater impact on the peak distance,and the peak distance of the heavy rain is smaller than that of the small rain.The above conclusions can be used as reference for further research on reducing the temperature rise of the friction pair and improving the current receiving quality.