Modal And Thermal Structure Coupling Analysis On Caliper Disc Brakes

As a important component of brake system in automotive active safety system,the brake is closely related to safety and comfort.Because of the stable braking efficiency,simple structure and easy maintenance,the caliper disc brake is is now widely used in passenger cars.During the braking,the caliper disc brake will suffered from the vibration and noise,thermal fatigue and other issues,the braking efficiency of the caliper disc brake has been greatly affected.Because of the serious effects of these problems are brought to the brake thermal structure coupling phenomena,it is important to study the caliper disc brake thermal structure coupling analysis.Based on a physical disc brake caliper,we use the CATIA to build a three-dimensional model and the ANSYS to do its finite element analysis pre-treatment.According to emergency braking condition of the caliper disc brake,we provide the basis for subsequent analysis by obtaining their mechanical boundary conditions by analysis,deducing its three-dimensional transient temperature field heat conduction equation and determining the boundary conditions of thermal analysis.We analyzed the vibration modes of the caliper disc brake.We exact and analyze the first six modal natural frequencies and mode shapes of brake caliper and the first ten modal natural frequencies and mode shapes of the brake disk,then find it that the brake disc and the outside world have overlapping excitation frequency which may causes the resonance.Then we exact and analyze the first ten modal natural frequencies and mode shapes of the brake disk after changing the axial dimension of the brake disc,the number of channels and the material properties of the ventilation parameters to find the effects of these parameters on the brake disc modes.The results show that increasing the elastic modulus of the brake disk can make the modal natural frequency of the brake disc to avoid external vibration frequency range to achieve the purpose of avoiding resonance.Based on vehicles’ emergency braking condition,we use the ANSYS software to simulate the thermal structure coupling procedure of the caliper disc brake and get the distribution of the contact pressure,temperature field and the stress field.It is can be obtained that the maximum contact pressure friction of the contact area located in the central area and the highest temperature region is also located in the central area after the simulation results being analyzed.At the start of braking,the brake disc temperature and stress fields were tested non-axially symmetric distribution,temperature and stress are showing greater difference in the radial and axial.With the development of braking,the temperature and stress field has a substantially axially symmetric distributions tend to appear temperature peak point and a radius of peak stress point of friction friction contact area.Based on the caliper disc brake vibration modal analysis and simulation of the thermal structure coupling,we provide a theoretical reference to select the design and materials to improve the structure of the brake.