Engineering, 11.02.2021 18:20 Kston2165

1. When the person is in still air in the middle of a summer day at T = 303 K, what is the skin surface temperature? Convection heat transfer to the air is characterized by a free convection coefficient of hfree = 2 W/m2 K. 2. Given the hot summer temperatures, the person starts using a fan and notices that her skin surface temperature drops by 1 K. What is the new convection coefficient, hfan, imposed by the fan? 3. At what temperature would the environment need to be for the person to experience the same skin surface temperature as in question 2 without the fan (i. e., only free convection)?

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1. When the person is in still air in the middle of a summer day at T = 303 K, what is the skin surf...

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