Papers by Keyword: Brake Disc

Abstract: The purpose of this study is to explore the effect of groove angle on the fatigue life of high-speed train brake discs. A thermal-mechanical coupling model of high-speed train brake discs with different angles (0°, 22.5°, 45°, 67.5°, and 90°) was designed and established. The effects of different groove angles on temperature and stress were studied and analyzed. Experimental specimens were prepared using special processing methods, and friction and wear characteristics experiments were carried out to further verify the simulation results. At the same time, based on the above results, life models of brake discs with different groove angles were established to study the effect of the angle on their fatigue life. Stress has a direct impact on the crack initiation life of groove brake discs, and temperature changes affect the material properties of brake discs, thereby affecting the crack initiation time. The crack growth life of 0° groove brake discs is longer, while the crack growth life of brake discs with other groove angles decreases as the groove angle decreases. Compared with the 0° groove angle, the crack propagation life of the 45° groove angle accounts for approximately 84.7%, while that of the 22.5° groove angle accounts for approximately 80.4%. These research results provide a theoretical basis and numerical research methods for the design of brake disc structures.

Abstract: The wear phenomenon of the braking surface of a high-power disc brake under emergency braking conditions is analyzed in this paper. Considering the classical Archard wear model, including the influence of the braking load, speed, and friction coefficient on the braking surface, the wear model of the brake disc surface is established to obtain the wear depth and distribution. It is essential to investigate the wear mechanism of the brake disc surface, and the evolution of wear laws is revealed under different braking parameters. The results have shown that the brake disc surface wear is constantly accumulating. The large load, the high speed, and the large friction coefficient would aggravate the surface wear area. It is expected that the wear study of the brake disc surface can guide the design of the disc brake.

Abstract: In order to guarantee the performant operation of the braking system of a racing car under high load an optimized thermal design of the braking system is an important factor. Especially in motorsports, a lot of braking energy is converted into heat due to short and intense braking events. Therefore, a suitable cooling concept is a crucial point to ensure a reliable thermal management of the braking system to dissipate the generated heat. In this work, the braking system of the formula student racing car of the UAS Esslingen is analysed using the racing car of the season 2019. A transient 1D simulation model of the heat balance of the braking system is created. For the determination of the heat transfer coefficients a steady 3D Conjugate Heat Transfer (CHT) simulation model is set up. The logging data of a real race are used for the validation of the presented model (s). The heat balance of the braking system, its entire heat flows as well as the time-dependent temperature evaluation of the brake disc are analysed and compared. The results of this analysis are used to create a cooling concept for the racing car’s braking system, to ensure an optimized braking performance over the entire race. Several different (geometrical) variants of the thermal design of the braking system are investigated using the above mentioned numerical models and the results are presented. Furthermore, the implementation of a cooling duct for the braking system is studied.

Abstract: A brake disc has an significant role in the vehicle and it is used to stop or decrease the velocity of the vehicle. The demand of metal matrix composites (MMCs) is greatly increased in fabricating the brake disc since it possesses a low density and high thermal conductivity. Over-heating will lead to the malfunction of the braking system and affect the safety of vehicle. Reduced weight of brake disc can decrease the use of fuel of the vehicle thus improve the fuel usage efficiency. This paper is focussed to determine the suitability of AlSiCGr hybrid MMCs compared to cast iron in terms of thermal and structural properties for brake disc. Both design of brake discs was proposed and modelled using CATIA and then imported to ANSYS software for structural and thermal analysis. The simulation results showed that AlSiCGr hybrid MMCs brake disc has higher thermal and structural performance compared to the original cast iron brake disc.

Abstract: An exact measurement of the disc brakes car temperature present difficulties, because the higher thermal stress is produced on the shiny metallic surface, which are in movement and in sliding contact with the brake pads. If an infrared camera is used for the thermal evaluating of the disc brakes, an important factor that must be considered is the reflected temperature. The aim of this research is to study the modification of the reflected temperature in correlation with the disk brake temperature and to establish a relationship for the estimation of this variation.

Abstract: The failure of brake performance, which is caused by thermal recession under the emergency brake, results in traffic accident frequently. Based on excellent wear-resisting properties of locust’s non-smooth surface structure, bionic brake disc with special surface micro-structure was designed. According to the thermal analysis theory, transient temperature field analysis of the bionic brake disc during the braking process under different initial velocity was analyzed. The results showed that bionic brake disc has excellent heat dissipation ability, which is beneficial to improve the brake performance. The non-smooth surface can store air and dissipate heat, thus reducing the thermal fatigue and thermal wear caused by temperature rise. This research provides a theoretical basis for designing bionic brake discs with excellent heat dissipation performance.

Abstract: This paper deals with the transient thermal analysis of brake disc of Variable Braking Force (VBF) system using computer software ANSYS. Generally, brake system is designed to apply frictional resistance to stop the vehicle. In VBF system the frictional resistance applied to the brake disc can be varied by changing the effective disc radius based on the pillion load. The rotor disc is commonly manufactured using cast iron (CI) or stainless steel (SS). In this work, these materials are taken for analysing the temperature distribution of VBF system. In addition to, an effort has been made here to suggest the best suited material for brake disc. By the way, it is evident that the rise in disc surface temperature is higher for VBF system compared with conventional system (constant effective disc radius (r) = 110mm).

Abstract: The uneven friction of brake disk leads to the brake failure, which frequently results in serious traffic accidents. Based on the excellent wear-resisting properties of locust’s non-smooth surface structure, bionic brake disc with special surface micro-structure was designed. Utilizing ANSYS Workbench, the braking time and the stress distribution of both the bionic model and the smooth model during the whole process of brake under different initial velocity were analyzed. Compared to the smooth model, results showed that the braking time and contact stress decrease in a certain extent, indicating brake disc with special surface micro-structure exhibits relatively excellent braking performance and wear resistance. The results provided theories for exploring an optimization the method used to design brake discs with excellent braking performance and wear resistance.

Abstract: In this paper sustainable analysis is performed due to the increasing demand for fuel efficiency. Current research focuses on high strength-light weight components in automobile which lead to the development of advance material parts with improved performance. A specific class of advanced material which has gained a lot of attention due for its potential is aluminium based metal matrix composites (Al-MMCs). Al-MMCs have some prospects for several applications in automobile parts. The analysis in this paper is a part of product development which plays a crucial role in determining a product's environmental impact. The objective was accomplished and thus to identify the potential of Al-MMCs rake disc for replacement of the conventional cast iron brake disc. The result indicated that the Al-MMCs have the potential to substitute the cast iron brake disc.

Abstract: The braking system is among the most significant active safety systems in a vehicle application for preventing injuries and property damage. Whether for light or heavy vehicles, brakes are no longer a small issue whereas it becomes a crucial problem to maintain the safety and to avoid the unpredictable cases especially on the road. Advanced technology in automotive industry has produced a new coming design of Magnetorheological (MR) brake which a field change is triggered off by changing the current in the coils exciting the magnetic field. MR fluid is one of the members of smart material which applicable usage to achieve the standard of rotary high speed similar as the existing brake disc in hydraulic system. A new MR brake disc was proposed using the squeeze mode rather than only conventional mode at the upper and lower rotating rotor. Parameters that have been considered are the types of MR fluid, selection of magnetic material, non-magnetic material and coil configurations. Then a finite elements analysis was performed to analyse the result of magnetic circuit and magnetic field strength within the MR brake configuration. MRF-140CG has been selected to represent the fluid to enhance the maximum magnetic flux density. The results showed that AISI 1020 and Stainless Steel 316 meet the requirement of material selection of magnetic and non-magnetic. Indirectly, yield stress has been significant increase when the magnetic field strength rises at certain value. Therefore, intention on design innovation of MR brake is useful to efficient control by upgrading function of those parameters which has been presented.