1. A hot pipe having surface temperature 245C is placed in a large enclosure. The enclosure...

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1. A hot pipe having surface temperature 245°C is placed in a large enclosure. The enclosure walls are at 98°C. The pipe surface can be assumed to be black. The total heat transfer coefficient including convection and radiation effects is 37 W/(m².K). Stefan-Boltmann constant a = 5.67 x 10* W/(m².K*). Calculate the rate of radiant heat transfer and the convective heat transfer at the pipe surface. Use the following equation for calculation. total heat loss by convection and radiation Qt = Qc + Qr he A (T1 - T2) rate of heat loss by radiation Qr = eGA (T- T) rate of heat loss by convection Qe %3D %3D 2. Calculate the loss of heat by radiation from a steel tube of diameter 70 mm and 3 m long at a temperature of 500K if the tube is located in a square brick conduit 0.3 m side at 300K. Assume the emissivity for steel to be 0.79 and for the brick conduit to be 0.93. Stefan-Boltmann constant G = 5.67 x 10* W/(m².K*). Use the following equation for calculation. GA1(T - T:) + A1 A2 (02 1. A hot pipe having surface temperature 245°C is placed in a large enclosure. The enclosure walls are at 98°C. The pipe surface can be assumed to be black. The total heat transfer coefficient including convection and radiation effects is 37 W/(m².K). Stefan-Boltmann constant a = 5.67 x 10* W/(m².K*). Calculate the rate of radiant heat transfer and the convective heat transfer at the pipe surface. Use the following equation for calculation. total heat loss by convection and radiation Qt = Qc + Qr he A (T1 - T2) rate of heat loss by radiation Qr = eGA (T- T) rate of heat loss by convection Qe %3D %3D 2. Calculate the loss of heat by radiation from a steel tube of diameter 70 mm and 3 m long at a temperature of 500K if the tube is located in a square brick conduit 0.3 m side at 300K. Assume the emissivity for steel to be 0.79 and for the brick conduit to be 0.93. Stefan-Boltmann constant G = 5.67 x 10* W/(m².K*). Use the following equation for calculation. GA1(T - T:) + A1 A2 (02

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Solution 1 Surface Temperature T Wall Temperature T2 245 C 98 C 2... View the full answer