The brake system drives the vehicle by converting the kinetic energy into thermal energy. The heat energy generated during the braking process increases the temperature of the structure. It causes thermal deformation due to overheating and causes cracks, noise, and vibration that degrade performance. However, it is not possible to fundamentally prevent the temperature rise of the brakes. There is a need for research on improving the heat dissipation performance by improving the shape of the brake. Therefore, this study analyzed the concentrated stress caused by overheating of the brake disc. In order to improve the performance of the disk, shape optimization design was performed. For stress and thermal analysis, the analysis was conducted using the finite element program ANSYS Transient Thermal and Structural tools. PIAnO (Process Integration and Design Optimization) was used to perform optimal design. In the formulation of the optimum design, the stress was minimized by satisfying the constraints. This study intends to present a new brake disc model by performing perforated shape and arrangement.

The purpose of this research is to reduce the weight of the brake system of vehicles and to increase braking performance and its durability and to shorten the stopping distance. The plans for light-weight vehicles are to develop light weight material itself which possesses superior properties and another way is to improve the manufacturing method of materials which have the better mechanical properties. And the materials used for this are aluminum alloy, magnesium alloy, titan alloy, steel, other metals, plastic, ceramic materials etc. In this research, aluminum is used for the main body of the break to reduce the weight of the brake and cast iron(SCM4), stainless steel(SUS304) and titan alloy(Ti Gr2) are used for the outer ring shape plate and assembled with bolts. Dynamometer test are braking performed on the brake disc. Based on the test results, stainless steel(SUS304) is optimized for the light-weight brake disc.

A numerical approach for ventilated disc brake with holes is carried out to investigate the effect of holes on the heat transfer characteristics. The numerical simulation code STAR-CCM+ is utilized to calculate flow and temperature fields with polyhedral meshes. The steady state results show that the holes make the flow velocity on the outer surface increasing, which induce the improvement of convective heat transfer on the outer surface. In the ventilated channel with holes, the convective heat transfer can be reduced due to the inflow of hot air through holes. In unsteady state, the disc has reached the highest temperature in 1,8s since the brake was engaged. The surface of disc without holes has maximum temperatures along the ventilated channels, while the surface temperatures of dis with holes are uniform.

In this paper, the relationship between the frequency split and the mode-coupling in the disc doublet mode, which is expressed according to the pattern of the surface of the disc, is utilized by using of 3 types(Chaos, Vent-hole, Normal). As the frequency split between the doublet mode disc that is expressed in the model through the interpretation is larger, and analogy through interpretation mode-coupling instability also lower. Vent-hole, which has a relatively large frequency split of disc doublet mode in 3 types(Chaos, Vent-hole, Normal) model, showed a large value of critical coefficient of friction in which mode-coupling instability is expressed. In addition, it was confirmed by analysis that the Vent-hole had a relatively large frequency split than the other models by analyzing the change in contact stiffness. It can be concluded that the larger the frequency split of the disc doublet mode, the lower the instability due to the mode-coupling.

The brake systems are composed of brake disc, brake pad and caliper and, these three parts play an important role for braking. In this study, heat fluid analysis is conducted for five different ventilated disc models, and two piece brake disc model separated in rotor and housing is used. In this case, each model has a different number of holes and vent shape. The basic heat flux and braking power equations are applied for the heat fluid analysis. The cooling performance with/without the braking operation is also analyzed for given five models where the material properties and boundary conditions are set to be identical. From our analysis results, it is found that the number of disc holes and ventilated pins strongly influences on the cooling performance.

The heat generated in contact type braking system can cause an unacceptable braking performance. Thermal behavior of ventilated disk brake system is presented in this paper. The temperature and velocity fields of 3-D unsteady simulated model are obtained using a software package "FLUENT". The numerical results show that there exits a temperature nonuniformity between the disk faces contacting with pads. The conduction rate through the disk and pad is calculated and the effect of material conductivity is also investigated.