BPK 142 Lecture Notes - Lecture 10: Wind Chill, Clothing Insulation, Thermal Conduction
16 Jun 2016
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Document Summary
Cold environments and human performance: heat balance deltatc ~= m - e +/- r +/- cd +/- cv humans are essentially tropical animals and are not equipped to deal w even mild cold. Death rate increases in varied temp environments: mechanisms of heat loss, radiation - the exchange of electromagnetic energy waves emitted from one object and absorbed by another. At room temp and naked, 60 % of your heat loss will be by radiation: we are all giving off radiation just like the desks we"re using. Manhattan effect: conduction - occurs whenever two surfaces with differing temperatures are in direct contact. Still air is an excellent insulator, while water is an excellent conductor. Heat conduction in water is about 25 times greater than in air because you have a much greater conductor surface in water and water can take a lot of heat. For example, heat transfer from skin to moving air or water.
