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In the present paper we introduce a monolithic CFD approach to simulate the cooling-down characteristics of disk brakes. To ensure a strong coupling between fluid and solid domain the overall transient thermal problem is solved within a single flow solver during the complete cooling-down process. We employ a fully implicit second order solution procedure. The experimental configuration consists of an inertia dynamometer including a generic 17 inch vented front disk with caliper, dust shield, bearing and knuckle. The validation is carried out for three different air flow velocities, with and without dust shield. The temperature is monitored via two thermocouples embedded into outer and inner rotor cheeks. In order to quantify the cooling-down characteristics, regression analysis are conducted on the temperature curves. The obtained cooling coefficient serves as comparison between measurement and computation.

High performance engines required in contemporary vehicles are causing underhood components to operate under hostile temperature environments. Aerodynamic styling and the addition of new components to the engine compartment further add to the problem by decreasing the volume of underhood cooling air flow. The addition of engine compartment coverings required to meet environmental noise reduction standards further restrict and debilitate air flow cooling. The above conditions demand that the analysis of air flow patterns and heat transfer phenomena under the hood be an essential part of early systems design of new engines, engine compartment components, and underhood component packaging. A numerical approach to calculate cooling air flow velocity and temperature distribution of the air and engine compartment components is utilized. Air flow is calculated using a finite volume Computational Fluid Dynamics code on a 220,000 cell representation of the flow domain.

This paper describes the design process of a complete HVAC module using computational fluid dynamics (CFD). CFD gives a detailed insight on the flow characteristics of HVAC components even in early design stages. Due to a close coupling with CAD/CAE systems the number of prototypes, costs, and development time can be reduced. Optimised air duct designs lead to reduced pressure losses, and turbulence levels, that consequently decrease flow induced noise. Simultaneously the air distribution of the duct outlets is uniformed. Thermal analysis gives information about the heat transfer and hot/cold air mixing process inside the HVAC module.