A large diffuse surface has spectral absorptivity of a -0.9 for à<1 jam and a=0.2 for 221 μm. The surface is insulated in the bottom, and exposed to two different conditions on thetop:InsulatedInsulatedCase (2)Case (1)6-1) Case 1): What is the value of the total hemispherical absorptivity of the large diffusesurface? Note that the sun emits approximately as a blackbody at 5800 K.Barkody Radiation FunctionATAT4000S0510144.00005720100000121G407541.3000021346633767BAYINDGOTIK540GA13000.0093410.700BATZ5.000230AND0.14025667541408180130672342800227697AND925010AND67012930003300316102692171.4007.40662992704006077600BA39102AND04411827806-2) Case 1): The surface is exposed to the sun and G.-1200 W/m². Flowing air temperatureTe is 300 K. Assuming the surface temperature of 7,- 320 K, what is the convective heattransfer coefficient? The answer should be given in the unit of W/(m²-K).6-3) Case 2): The surface is shielded from the sun by a large diffuse and gray plate with an pof 0.8. Flowing air has a temperature Te of 300 K and a convective heat transfer coefficient of40 W/(m²K). If we want to keep T.-320 K, what is the top plate temperature 7,? The answershould be given in the unit of K.300an

Answered: Image /qna-images/answer/5b09e5c8-9fa4-48f8-945a-fda55f669788.jpg

A large diffuse surface has spectral absorptivity of a=0.9 for 2 <1 jam and -0.2 for 2.2 1 μm. The surface is insulated in the bottom, and exposed to two different conditions on the top: Insulated Insulated Case (1) 6-1) Case 1): What is the value of the total hemispherical absorptivity of the large diffuse surface? Note that the sun emits approximately as a blackbody at 5800 K. AT AT 310 4.000 6477 an 430 0304 NO 4000 AND 640754 GOIZE 0002134 1.300 BARITAT 140 5300 5.40 BA L300 0:009341 6.70106 BATZ 0720178 230 9.1 8140256 8180130 6,40 676234 280 0227997 AND 8250108 AND 670129 0273232 7000 3300 0316102 7.30 GRINZIT 1400 7.40 3800 0400607 7:00 BAY9I02 0443182 7800 BAINA 6-2) Case 1): The surface is exposed to the sun and G. 1200 W/m². Flowing air temperature Te is 300 K. Assuming the surface temperature of 7,- 320 K, what is the convective heat transfer coefficient ? The answer should be given in the unit of W/(m²-K).

A large diffuse surface has spectral absorptivity of a=0.9 for 2 <1 jam and -0.2 for 2.2 1 μm. The surface is insulated in the bottom, and exposed to two different conditions on the top: Insulated Insulated Case (1) 6-1) Case 1): What is the value of the total hemispherical absorptivity of the large diffuse surface? Note that the sun emits approximately as a blackbody at 5800 K. AT AT 310 4.000 6477 an 430 0304 NO 4000 AND 640754 GOIZE 0002134 1.300 BARITAT 140 5300 5.40 BA L300 0:009341 6.70106 BATZ 0720178 230 9.1 8140256 8180130 6,40 676234 280 0227997 AND 8250108 AND 670129 0273232 7000 3300 0316102 7.30 GRINZIT 1400 7.40 3800 0400607 7:00 BAY9I02 0443182 7800 BAINA 6-2) Case 1): The surface is exposed to the sun and G. 1200 W/m². Flowing air temperature Te is 300 K. Assuming the surface temperature of 7,- 320 K, what is the convective heat transfer coefficient ? The answer should be given in the unit of W/(m²-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 11.64P

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