Engineering, 14.09.2019 01:20 okstyles

Calculate the steady-state temperature for a metal roof and comment on whether a cat would be able to comfortably walk across the roof. the roof initially has a uniform solar heat flux of g = 750 w/m2 and has emissivity of 0.13 and solar absorptivity of 0.65. the large surrounding sky is at an effective temperature of 275 k. air over the roof is not moving much and provides a convective heat transfer coefficient of 7 w/m2k and the air temperature is 16oc. assume that the lower side of the roof is well insulated. a) make a sketch of the roof and use arrows and labels to show the heat transfer to and from the roof. b) calculate the temperature of the roof for the case described in the problem statement. c) during the solar eclipse for louisville, the coverage of the sun was 96%. calculate the steady-state (even though the maximum eclipse only lasted a few minutes, we are going to assume a steady-state condition) temperature of the roof during the solar eclipse.

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