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On the Efficiency of Cooling Surfaces with Fins Containing Internal Heat Sources

Authors: Eliseev V.N., Tovstonog V.A., Borovkova T.V. Published: 07.04.2014
Published in issue: #2(95)/2014  

DOI:

 
Category: Simulation of Processes  
Keywords: efficiency, rods, fins, cooling, internal heat release, semitransparent materials, optimum thickness

Characteristics of heat transfer in the fins (rods) that contain internal heat sources uniformly distributed within their volume are considered. The analytical relationships are obtained that allow the effectiveness of finned surface to be analyzed and evaluated. As a practical application, a problem is considered regarding the use of such fins in the design of powerful water-cooled gas-discharge radiation sources, in which the sheath can be made of leuco sapphire. It is shown that the internal heat release in the fins reduces heat removal from the cooled wall as compared to the fins without internal heat sources. At the levels of heat release that are typical for powerful gas-discharge radiation sources, the internal heat release in the fins has little effect on their efficiency. It is noted that the addition of fins to the sheaths made of leuco sapphire markedly increases the efficiency of their cooling, reduces the consumption of coolant, and consequently reduces hydraulic resistance of the flow path. However, the technology of manufacturing the sheaths with thin fins made of brittle material and difficulties of their exploitation become critically important in this case.

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