Consider two large parallel plates, one at T1-7270C with emissivity e1 = 0.8 and the other at T2 = 2270C with emissivity e2 = 0.4. An aluminum radiation shield with an emissivity, e3=0.05 on both sides is placed between the plates. Calculate the percentage reduction in heat transfer rate between the two plates as a result of the shield.
Use s = 5.67 ´ 10–8 w(m2K4).