• question_answer Two long parallel surfaces, each of emissivity 0.7, are maintained at different temperatures and accordingly have radiation exchange between them. It is desired to reduce 75% of this radiant heat transfer by inserting thin parallel shields of equal emissivity (0.7) on both sides. What would be the number of shields? A) 1                                 B) 2C) 3                                 D) 4

Solution :

Heat transfer with shields $=\left( \frac{1}{n+1} \right)\times$ Heat transfer without shields Where n = number of shields $\frac{1}{n+1}=\frac{1}{4}$ Or n=3

You need to login to perform this action.
You will be redirected in 3 sec