Vehicle thermal design traditionally depends heavily on prototype testing in thermal wind tunnels or on-road testing with hundreds of thermocouples. The testing process is very expensive, time consuming, and inflexible. Testing involves thermocouple instrumentation that requires test engineers to estimate a priori where thermal problems might occur — but the highly turbulent nature of underbody flows makes this very difficult or impossible to predict. Relying on redesign and retesting is an expensive hit-or-miss process that often ultimately fails to identify the highest temperature locations. The inherently transient nature of turbulent flow is almost impossible to visualize in a wind tunnel, yet these complex structures must be understood in order to optimally locate and protect components. In addition, temperature is a function of the complex interaction between conduction, radiation, and convection in the surrounding fluid, especially for very hot components. Accurately predicting this is extremely challenging.
Given that there is increasing pressure from the marketplace to speed up and improve the vehicle development process, it is clear that a more effective method is required to address thermal protection early in the vehicle design process. A high-fidelity simulation is necessary to capture the relevant physics in order to solve thermal protection problems.
