Structural Design And Experimental Study Of Aluminum Alloy Brake Disc Based On Multi Field Coupling

Saving resources has become the basic national policy of our country,and the Transportation Commission has also put forward the development strategy of strengthening transportation,saving expenditure and reducing consumption,and green environmental protection.As an important part of vehicle unsprung weight,brake disc has obvious lightweight effect.High heat dissipation structure design and lightweight materials are the main ways to reduce the weight of brake disc.Due to frequent braking of urban rail trains,the heat accumulation of steel brake disc and the thermal damage caused by it are obvious.Based on the project of aluminum matrix composite brake disc for a metro train in Nanjing,the high thermal dissipation structure design of brake disc is carried out by means of thermal-fluid-solid coupling and test.Based on the CFD analysis method,Star CCM+ software,combined with the speed range of metro train,according to the type and distribution characteristics of wheel mounted brake disc cooling ribs,the heat dissipation performance and pumping power of cooling ribs at different speeds are studied.At the same time,considering the forming process of brake disc,the type and distribution form of cooling ribs of brake disc are optimized,namely plate-shaped cooling ribs and overall radial distribution.According to the flow field analysis results,combined with the interface size requirements of the brake disc,the structure design of the aluminum alloy brake disc was completed.The thermal analysis of the brake disc under the conditions of 100 km/h three times of emergency braking and the 100 km/h whole round trip braking was carried out by using the thermal-fluid-solid coupling simulation calculation method.The differences of the simulation results of the brake discs on both sides of the wheel were compared and analyzed.The maximum temperature of three times of emergency braking is 183.0 ?,the maximum stress is 167 MPa,the maximum temperature of the whole round trip is 194.9 ?,the maximum temperature is far less than the allowable temperature of aluminum matrix composite 350 ?,and the maximum stress is far less than the tensile strength of the material at the corresponding temperature.The temperature of the brake disc on the outside of the wheel is higher than that on the inside of the wheel,the stress amplitude is larger,and it is more prone to failure.The test results show that the temperature simulation results are in good agreement with the test results,and the designed brake disc meets the requirements of the given working conditions.The research results of this paper can promote the localization and engineering application of aluminum matrix composite brake disc,and have good engineering application value.