On a multi-layered square wall, the thermal resistance of the first layer is 0.005 ° C / W, the resistance of the second layer is 0.3 ° C / W, and the third layer is 0.1 ° C / W. The overall temperature gradient in the wall is multilayered from one side. to the other side is 50 ° C. a. Determine the heat flux through the walls. = Answer watts / m2. b. If the thermal resistance of the second layer is changed to 0.1 ° C / W, what is the effect in% on heat flux, assuming the temperature gradient remains the same? = AnswerAnswer %.
The thermal resistance of first layer is .
The thermal resistance of second layer is .
The thermal resistance of third layer is .
The temperature gradient is .
(a)
The expression for the total resistance of composite wall is given as,
Substitute the values,
The expression for the heat flux can be given as,
Substitute the values,
Thus, the heat flux through the walls is .
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