Numerical Heat Transfer Simulations of Brake Discs under Dyno-Test Load Cases

Abstract

Automotive brake discs are critical safety components whose performance heavily relies on efficient thermal dissipation. Yet, conventional laboratory dynamometer testing remains costly and time-consuming. To address this challenge, this study establishes a reliable CFD methodology to simulate and visualize complex aerothermal behavior before physical dynamometer testing, enabling evaluation even during the early design and development stages. Specifically, the thesis investigates the temperature-dependent Heat Transfer Coefficients (HTCs) of brake discs across a wide temperature and velocity spectrum. The thermal simulations and analysis revealed a distinct decline in the localized HTCs of the brake disc surfaces as temperatures increased. By parameterizing the fluid boundaries, this work isolates the explicit influences of temperature-dependent fluid properties, rotor rotational speed, rotational direction, and the test-bench’s volumetric inlet airflow rate on convective dissipation. This case study approach was systematically applied across both ventilated and solid brake disc geometries to evaluate structural cooling trade-offs. Finally, an experimental validation was conducted by mapping physical thermocouple data embedded within a test rotor against a transient thermal model in Abaqus FEM software, successfully correlating the numerical boundary conditions with real-world dynamometer temperature data.