Reconsider Prob. 13–91. Using EES (or other) software, investigate the effects of the number of the aluminum sheets and the emissivities of the plates on thenet rate of radiation heat transfer between the two plates. Let the number of sheets vary from 1 to 10 and the emissivities of the plates from 0.1 to 0.9. Plot the rate of radiation heat transfer as functions of the number of sheets and the emissivities of the plates, and discuss the results.

Data from problem 91

Five identical thin aluminum sheets with emissivities of 0.1 on both sides are placed between two very large parallel plates, which are maintained at uniform temperatures of T₁ = 800 K and T₂ = 450 K and have emissivities of ε₁= ε₂ = 0.1, respectively. Determine the net rate of radiation heat transfer between the two plates per unit surface area of the plates and compare the result to that without the shield.