Buoyancy effects on laminar impinging jets

Abstract A laminar, heated, two-dimensional jet impinging on an isothermal surface has been studied to determine the effects of buoyancy on the flow and thermal structure of the region near impingement. The parameters used include the jet exit Reynolds number, Richardson number, and separation distance between the impinging surface and the jet exit. Results of the velocity profile, temperature distribution, local friction factor, and heat transfer coefficient are presented for both upward and downward facing jets. It is found that the local Nusselt number experiences a peak away from the axis of the jet which is enhanced for highly buoyant flows. In general, the enhancement of the heat transfer rate is substantial for high Richardson number conditions.

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