Thermal Structure Coupling Analysis And Structural Optimization Of Disc Brake For Mining Electric Locomotive

As the main transportation tool under the mine,mining electric locomotive is of great significance to the production process under the mine.Disc brake has been gradually applied to mining electric locomotive because of its small size,compact structure,large braking torque,stable braking efficiency and good heat dissipation performance.The braking process of disc brake is a typical thermal structure coupling process.In this process,the temperature field and stress field interact with each other.In the long run,the brake disc will eventually cause fatigue damage due to the effect of thermal stress cycle,which will have a certain impact on the braking performance of mining electric locomotive.More importantly,General Technical Conditions for Coal Mine Explosion-proof Battery Electric Locomotive stipulates that the temperature of brake surface of electric locomotive can not exceed 150℃.Therefore,the thermal structure coupling problem of disc brake during braking process is studied and analyzed,and the structure of disc brake is optimized to effectively reduce the temperature and stress in the braking process.And it is very important to ensure the safe transportation of underground and improve the braking performance of mining electric locomotive.This paper takes the disc brake for 5t mining electric locomotive as the research object.The main research contents include the following aspects.On the basis of consulting the relevant literatures at home and abroad and carrying on the theoretical analysis to the thermal structure coupling problem,according to the specific performance parameters of mining electric locomotive,the working condition of disc brake was obtained through theoretical calculation,and the boundary conditions and load constraints for simulation calculation were determined.Based on the material performance parameters of brake disc and friction block changing with temperature,the three-dimensional finite element model of disc brake is established by using finite element analysis software ABAQUS,and the thermal structure coupling simulation analysis is carried out.The distribution of temperature field and stress field of brake disc during braking process are obtained and analyzed from radial,circumferential and axial directions respectively.The interaction between temperature field and stress field during braking process of disc brake for mining electric locomotive is studied,and the coupling mechanism of thermal structure is further revealed.When the working conditions are set keep up with the simulation analysis,the Link3900NVH inertial bench test machine is used to test the temperature change at the designated point during the braking process of disc brake.The test data and simulation results were compared and analyzed to verify the correctness of the finite element model.According to the structural characteristics of limited installation space of disc brake for mining electric locomotive and the related research of predecessors,the structural parameters for optimizing disc brake are determined.Combined with the thermal structure coupling simulation results of temperature field and stress field of disc brake for mining electric locomotive,the optimization index is determined,and the orthogonal test is designed to optimize the structure of disc brake.According to the orthogonal test results.The primary and secondary factors affecting the distribution of temperature field and stress field and the preliminary optimization scheme are determined by visual analysis method.Variance analysis method was used to determine the importance of each factor to the test results and the magnitude of the error.Finally,the optimal combination scheme of structural parameters of disc brake is determined.The optimization scheme is simulated and analyzed,and compared with the simulation results of the original scheme,which proves the feasibility of the optimization scheme.