Theory of heat transfer from a surface covered with hair

Journal Article · Wed Aug 01 04:00:00 EDT 1990 · Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States)

DOI:https://doi.org/10.1115/1.2910438· OSTI ID:5233350

Bejan, A ^[1]

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1. Duke Univ., Durham, NC (USA)

This paper describes the fundamental mechanisms of heat transfer through a surface covered with perpendicular hair strands of uniform density. An air flow parallel to the skin seeps through the spaces created between the hair strands. It is shown that the total heat transfer rate from the surface is due to two contributions: (i) the heat conducted through the hair strands, which act as fins, and (ii) the heat convected from the bare portions of the skin. When the air flow is slow enough to conform to the Darcy regime, there exists an optimum hair strand diameter for which the total heat transfer rate is minimum. The optimum diameter increases as the square root of the length swept by the air flow, that is the linear size of the body of the animal covered with hair.

• OSTI ID: 5233350
• Journal Information: Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States), Journal Name: Journal of Heat Transfer (Transactions of the ASME (American Society of Mechanical Engineers), Series C); (United States) Vol. 112:3; ISSN 0022-1481; ISSN JHTRA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
AIR FLOW
BODY
DARCY LAW
ENERGY TRANSFER
FLUID FLOW
GAS FLOW
HAIR
HEAT TRANSFER
ORGANS
SKIN
THERMAL INSULATION