A combined computational/ experimental analysis is conducted to investigate the cooldown behavior of a surrogate engine mount assembly. The engine mount in an automobile is often in the close proximity of the catalytic converter, and may heat up significantly during operation of the vehicle. When the vehicle is parked after operation, the mount cools due to heat loss by natural convection and radiation. The objective of this study is to develop a model that is capable of accurately predicting the spatio-temporal evolution of the mount temperature during this cooldown process. Carefully controlled experiments were first conducted, during which temperatures were recorded at 41 different locations. A Computational Fluid Dynamics (CFD) model that includes natural convection and radiation was next developed to simulate the same experiments. The simulations were conducted using roughly 5–6 million control volume (cells). The mesh was generated using ANSA™ and parallel computations of the governing equations were conducted using Ansys-Fluent™. The CFD results were found to agree with the measured temperatures to within a few tens of degrees. The discrepancies may be attributed to differences in initial conditions (measured versus numerical) and due to the fact that thermal contact resistances were neglected. However, the study revealed that to obtain reasonably close agreement, one must use very small time step sizes — small enough to sufficiently resolve the rapidly changing unsteady natural convection patterns — making such computations extremely time-consuming.

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