Abstract
Under certain conditions, the heat transfer rate from a surface covered with hair is due to two competing effects: i) the heat transfer to the slowed air flow, through the bare portions of the skin, and ii) the heat transfer through all the hair strands, which act as fins. One result of this competition is the existence of an optimum hair strand diameter for minimum overall heat transfer. In forced convection, the optimum hair strand diameter increases as the length of the skin surface, raised to the power 1/2. In natural convection, the optimum diameter is proportional to the height of the skin surface raised to the power 1/4. These trends agree qualitatively with measurements of the hair sizes of various mammals.
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© 1991 Springer Science+Business Media Dordrecht
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Bejan, A., Lage, J.L. (1991). Heat Transfer from A Surface Covered with Hair. In: Kakaç, S., Kilkiş, B., Kulacki, F.A., Arinç, F. (eds) Convective Heat and Mass Transfer in Porous Media. NATO ASI Series, vol 196. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-3220-6_28
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DOI: https://doi.org/10.1007/978-94-011-3220-6_28
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