Spectral hemispherical reflectivity distribution of an opaque surface is shown below. Surface is subjected to the spectral irradiation as shown.1.0400a 0.4200510 15 20a (um)510152 (um)Calculate the total irradiation on the surface in W/m2Calculate the irradiation absorbed by the surface in W/m23250 || 3750 || 4250|| 5000 || 5750|| 6250|| 75001050 || 12001400|| 1600|| 1750| 1850 || 2000

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Spectral hemispherical reflectivity distribution of an opaque surface is shown below. Surface is subjected to the spectral irradiation as shown. 1.0 400 0.4 200 10 15 20 2 (um) 5 10 15 2 (um) Calculate the total irradiation on the surface in W/m2 Calculate the irradiation absorbed by the surface in W/m² ( 3250 3750 || 4250|| 5000 || 5750| 6250 || 7500 1050 || 1200 || 1400|| 1600 || 1750 || 1850 || 2000

Spectral hemispherical reflectivity distribution of an opaque surface is shown below. Surface is subjected to the spectral irradiation as shown. 1.0 400 0.4 200 10 15 20 2 (um) 5 10 15 2 (um) Calculate the total irradiation on the surface in W/m2 Calculate the irradiation absorbed by the surface in W/m² ( 3250 3750 || 4250|| 5000 || 5750| 6250 || 7500 1050 || 1200 || 1400|| 1600 || 1750 || 1850 || 2000

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 11.66P

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11.68 Two infinitely large, black, plane surfaces are 0.3 m apart, and the space between them is filled by an isothermal gas mixture at 811 K and atmospheric pressure. The gas mixture consists of by volume. If one of the surfaces is maintained at 278 K and the other at 1390 K, calculate (a) the effective emissivity of the gas at its temperature, (b) the effective absorptivity of the gas to radiation from the 1390 K surface, (c) the effective absorptivity of the gas to radiation from the 278 K surface, and (d) the net rate of heat transfer to the gas per square meter of surface area.
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1.26 Repeat Problem 1.25 but assume that the surface of the storage vessel has an absorbance (equal to the emittance) of 0.1. Then determine the rate of evaporation of the liquid oxygen in kilograms per second and pounds per hour, assuming that convection can be neglected. The heat of vaporization of oxygen at –183°C is .
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