Dynamic analysis of three autoventilated disc brakes

Abstract

The braking system of a car must meet several requirements, among which safety is the most important. It is also composed of a set of mechanical parts such as springs, different types of materials (Metallic and Non Metallic), gases and liquids. The brakes must work safely and predictably in all circumstances, which means having a stable level of friction, in any condition of temperature, humidity and salinity of the environment. For a correct design and operation of brake discs, it is necessary to consider different aspects, such as geometry, type of material, mechanical strength, maximum temperature, thermal deformation, cracking resistance, among others. Therefore, the main objective of this work is to analyze the dynamics and kinetics of the brake system from the pedal as the beginning of mathematical calculations to simulate the behavior and Analysis of Finite Elements (FEA), with the help of SolidWorks Simulation Software. The results show that the third brake disc works best in relation to the other two discs in their different working conditions such as speed and displacement in braking, concluding that depending on the geometry of the brake and the cooling channels these systems can be optimized that are of great importance for the automotive industry.Keywords: Dynamics, friction, FEA, CFD, disc brakes, automobile. RESUMENEl sistema de frenado de un automóvil debe satisfacer varios requerimientos, entre los cuales, la seguridad es el más importante. Además, está compuesto por un conjunto de piezas mecánicas tales como: resortes, diferentes tipos de materiales (Metálicos y No Metálicos), gases y líquidos. Los frenos deben trabajar en forma segura y predecible en cualquier circunstancia, lo cual implica disponer de un nivel estable de fricción en cualquier condición de temperatura, humedad y salinidad del medio ambiente. Para un correcto diseño y operación de los discos de freno, es necesario considerar diferentes aspectos, tales como la geometría, el tipo de material, la resistencia mecánica, la temperatura máxima, la deformación térmica, la resistencia al agrietamiento, entre otros. Por lo anterior, el principal objetivo de este trabajo es analizar la dinámica y la cinética del sistema de freno a partir del pedal como inicio de los cálculos matemáticos para simular el comportamiento en mediante el Análisis de Elementos Finitos (FEA), con la ayuda del Software SolidWorks Simulation. Los resultados demuestran que el disco de freno número tres funciona mejor con relación a los otros dos discos en sus diferentes condiciones de trabajo, como lo son velocidad y desplazamiento en frenado. Así, se concluye que dependiendo de la geometría del freno y de los canales de refrigeración, se pueden optimizar estos sistemas de gran importancia para la industria automotriz.

Análisis termodinámico de un disco de freno automotriz con pilares de ventilación tipo NACA 66-209

“…El disco se ve afectado por varios tipos de convección: en la parte frontal, en sus laterales y en su periferia. A continuación, se determinará la transferencia de calor por convección en cada tipo [38] [39].…”

Análisis del caudal de aire en un disco de freno automotriz con alabes de ventilación tipo N-38

“…Also, Figure 2 represents the distribution of the profiles on the disk with an angle of β1=60°. For the calculations, the procedure of the geometric outline of the curvature of a radial centrifugal impeller was taken into account, taking into account the method of the Kaplan error triangle, which considers the total development of the ventilation pillar in its entire length, angles and thicknesses in order to make the mathematical considerations of the surrounding flow in the brake disc [18]. Taking into account previous work, a configuration of 15 of classic N-38 profile was established.…”

“…In most cases, designs must avoid overheating that arises between the brake and the pad due to the effect of friction, also taking into account the physical, mechanical and chemical properties of the materials used in the braking system [8] [9]. The design phase of ventilated disc brakes, it is very important to analyze the behavior of the associated thermo-fluids (surrounding air) where the characteristics and operation of the fluids on the surface of the disc can be observed always guaranteeing the effectiveness of the process for braking and heat dissipation through the surface and ventilation channels [10] [11]. The heat dissipation heat and the performance of the ventilated disc brakes depends largely on the aerodynamic characteristics of the airflow, through ventilation channels and disk brake geometry configurations, which are checked by the implementation of CAD design software that includes the Computational Fluid Dynamics library (CFD) [12] [13].…”

Composite materials reinforced with ceramic waste and matrix of unsaturated polyester for applications in the automotive industry

“…Operating conditions for a brake lever were parameterized by real performance in limited circumstances, taking into account that the braking system is the most important component in vehicles to maintain the integrity of the passengers [14]. Consequently, it was assumed that the time needed to reach the maximum grip strength was less than 2 seconds, and the optimal values of maximum voluntary contraction are obtained within a period of 3 seconds [15].…”