48. Consider two large parallel plates, one at T, -800 K with emissivity &, -0.9 and...

Transcribed Image Text:

48. Consider two large parallel plates, one at T, -800 K with emissivity &, -0.9 and the other at T, 300 K with emissivity &,-0.5. A radiation shield with an emissivity, (on both sides) is placed between the plates. Calculate the emissivity of the radiation shield needed to reduce the heat transfer rate to 10 percent of that without the shield, Answer: 0.1 48. Consider two large parallel plates, one at T, -800 K with emissivity &, -0.9 and the other at T, 300 K with emissivity &,-0.5. A radiation shield with an emissivity, (on both sides) is placed between the plates. Calculate the emissivity of the radiation shield needed to reduce the heat transfer rate to 10 percent of that without the shield, Answer: 0.1