Question

Problem 6 (10 рoints) A gray surface has a directional total emissivity that depends on angle of incidence as E(0) 0.788 cos 0. Uniform radiant energy from a single direction normal to the cylinder axis is incident on a long cylinder of radius R. What fraction of energy striking the cylinder is reflected? What is the result if the body is a sphere rather than a cylinder? Qincident R All problems taken from John Howell, M. Minar Mengüc, and Robert Siegel, Thermal Radiation Heat Transfer, 6th Edition, CRC Press (2015)

Answer 1

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