Simulation Research For Ventilation Disc Brake Friction Heat Generation

Brake is a key component of the brake system,and its thermodynamic performance has an important impact on the safety of the car.During the braking process,the friction between the brake disc and the brake block generates a large amount of heat,causing the brake temperature to rise rapidly,resulting in a decrease in braking performance.The simulation study of brake friction heat generation is an important method for heat dissipation and structural improvement of brakes.Based on the domestic and international simulation of brake friction heat generation,this paper applies the theory of contact,friction,heat conduction and deformation body stress and strain to discuss the whole process of brake friction heat generation,and describes the disk and system in detail.The thermodynamic mechanism of the moving block during the entire brake friction process.Combined with the engineering practice,a three-dimensional model of the original thermodynamic analysis of the curved blade ventilated disc brake was established.The boundary parameters such as material parameters,mesh,load and displacement,convective heat transfer coefficient and time step parameters were set.On this basis,the finite element transient thermodynamics method is used to simulate the friction and heat generation of the model,and the variation of the temperature and stress of the circumferential,radial and axial directions of the brake disc of the original model is also summarized.The strain in the thickness direction of the moving plate was studied.Then,the structure of the original brake disc is improved,and the thickness of the disc wall is changed and the friction heat generation process is simulated while maintaining the overall thickness of the brake disc.Based on the improvement of the wall thickness of the ventilated brake disc,the simulation analysis of the number and structure of different heat dissipating ribs is carried out,and the analysis results of the original model and the improved model are compared.According to the research,compared with the original brake disc,the maximum temperature of the brake disc with improved wall thickness decreased by 16% during the complete braking process,and the maximum temperature of the brake disc that changed the cooling rib decreased by 9%.When the overall thickness of the brake disc is kept constant and the thickness of the disc wall is changed,the axial and radial temperature gradients of the brake disc are reduced;when the brake disc rib structure is changed based on the model of changing the thickness of the disc wall,Both the axial and radial temperature gradients of the moving plate are reduced,and the deformation in the thickness direction is basically the same as the original model,and the mechanical properties of the disk can be ensured.The research in this paper shows that the thermodynamic performance of the brake disc with improved structure is improved,which is beneficial to optimize the braking performance of the brake and the safety of the vehicle.