A half cylindrical shell with a radius of 75 cmis held at 200°C and has an emissivity of 0.4. A long200°CR= 75 cmcylinder has a diameter of 30 cm and is placed20°CE= 0.4D= 30 cmconcentrically with the shell. The cylinder is radiativelyblack. At the instant the cylinder is 20°C, how much heatis exchanged from the shell to the cylinder, per meterlength into the page, i.e., Qshell-eylinder/L.

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A half cylindrical shell with a radius of 75 cm is held at 200°C and has an emissivity of 0.4. A long cylinder has a diameter of 30 cm and is placed concentrically with the shell. The cylinder is radiatively black. At the instant the cylinder is 20°C, how much heat is exchanged from the shell to the cylinder, per meter length into the page, i.e., Qshell-cylinder/L. 20°C D = 30 cm 200°C R = 75 cm &= 0.4

A half cylindrical shell with a radius of 75 cm is held at 200°C and has an emissivity of 0.4. A long cylinder has a diameter of 30 cm and is placed concentrically with the shell. The cylinder is radiatively black. At the instant the cylinder is 20°C, how much heat is exchanged from the shell to the cylinder, per meter length into the page, i.e., Qshell-cylinder/L. 20°C D = 30 cm 200°C R = 75 cm &= 0.4

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 11.3P: Determine the total average hemispherical emissivity and the emissive power of a surface that has a...

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