NUMERICAL PREDICTIONS OF FLOW STRUCTURE ABOVE A DIMPLED SURFACE IN A CHANNEL

Turbulent air flow in a channel with deep dimples (δ/D = 0.3) on one wall is numerically predicted using version 6.0.12 of FLUENT with a realizable κ–ϵ model and no wall function. Steady-state results show centrally located vortex pairs, as well as vortex pairs located near the spanwise edges of individual dimples. The fluid within and near these different vortex pairs contains augmented magnitudes of eddy diffusivity for momentum and eddy diffusivity for heat. Such characteristics are due to advection of reattaching and recirculating flow from locations within the dimple cavities, as well as to the strong instantaneous secondary flows and mixing within the vortex pairs.

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