Análise computacional por elementos finitos do impacto da geometria e do material no desempenho térmico de discos de freio automotivos

Abstract

The braking system is directly linked to vehicle safety. Currently, automobiles use two main types of brakes: disc and drum brakes. Proper sizing of all components in this system is essential to ensure its performance. In this context, the present study aimed to analyze, through computational simulations based on the finite element method, the thermal behavior of different types of brake discs subjected to intense and extreme braking conditions. Three brake discs (solid, ventilated, and perforated) were simulated, with different materials used: 1060 Aluminum Alloy, Gray Cast Iron, and SAE 1020 Steel, in three different scenarios: a downhill braking, an emergency braking, and 15 consecutive braking events with cooling time between each. The results indicated that ventilated discs demonstrated significantly superior performance compared to solid discs in terms of heat dissipation. The highest recorded temperature was 576°C for the solid cast iron disc during a 320-second downhill braking event. In comparison, the conventional ventilated disc reached 380°C, while the ventilated and perforated disc reached 363°C, both also made of cast iron, reinforcing the superiority of ventilated models in cooling efficiency. Furthermore, material selection had a significant impact on the results, with aluminum exhibiting the best heat dissipation compared to steel and cast iron. Based on these analyses, it is concluded that ventilated discs should be prioritized for high-braking-load situations, such as in front axles, while solid discs, being more cost-effective but less efficient, are more suitable for rear axles.