7. An opaque horizontal flat plate has a top surface area of 2 m2, and its edges and lower surface are well insulated. The plate is uniformly irradiated at its top surface at a rate of 1200 W. Consider steady state conditions for which 1000 W of the incident radiation are absorbed. The plate surface temperature is 350 K and heat transfer by convection from the surface is 400 W such that the net radiation is zero. Determine: (10points) (a) The reflected incident radiation, in W/m². (b) The emissive power, in W/m². (c) Is the surface of the plate diffuse-gray? Prove your answer. (+5 BONUS points¹) Insulation Ts = 350 K

7. An opaque horizontal flat plate has a top surface area of 2 m2, and its edges and lower surface are well insulated. The plate is uniformly irradiated at its top surface at a rate of 1200 W. Consider steady state conditions for which 1000 W of the incident radiation are absorbed. The plate surface temperature is 350 K and heat transfer by convection from the surface is 400 W such that the net radiation is zero. Determine: (10points) (a) The reflected incident radiation, in W/m². (b) The emissive power, in W/m². (c) Is the surface of the plate diffuse-gray? Prove your answer. (+5 BONUS points¹) Insulation Ts = 350 K

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter11: Heat Transfer By Radiation

Section: Chapter Questions

Problem 11.23P

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