14. A 6-foot-long circular pipe used to transfer hot water has inner and outer diameters of 1 inch and 1.25 inches, respectively. The pipe is made of copper. The copper alloy is unknown. Inside the pipe, hot water (170 °F) flows very quickly (average velocity is 20 ft/sec.) The convective heat transfer coefficient between the flowing water and the inside of the pipe is unknown. The properties for water at this temperature are: Thermal Conductivity = 0.385 Btu/hr-ft-°F Specific Heat = 1.001 Btu/lbm-°F Density = 61 lbm/ft³ The environment outside the pipe is 73 °F air and the convective heat transfer coefficient is 2.2 Btu/hr-ft²-°F. 170 °F water flow at 20 ft/sec Room air, 73 °F, heat transfer coefficient - 2.2 6 feet A 1 inch 1. Estimate the rate of heat transfer and the air. 1.25 inches from the flowing water 2. Estimate the temperature change of the water as it moves through the 6-foot length of pipe. Hint: The mass flowrate of the water is: PAV, where is the average velocity of the pipe.

14. A 6-foot-long circular pipe used to transfer hot water has inner and outer diameters of 1 inch and 1.25 inches, respectively. The pipe is made of copper. The copper alloy is unknown. Inside the pipe, hot water (170 °F) flows very quickly (average velocity is 20 ft/sec.) The convective heat transfer coefficient between the flowing water and the inside of the pipe is unknown. The properties for water at this temperature are: Thermal Conductivity = 0.385 Btu/hr-ft-°F Specific Heat = 1.001 Btu/lbm-°F Density = 61 lbm/ft³ The environment outside the pipe is 73 °F air and the convective heat transfer coefficient is 2.2 Btu/hr-ft²-°F. 170 °F water flow at 20 ft/sec Room air, 73 °F, heat transfer coefficient - 2.2 6 feet A 1 inch 1. Estimate the rate of heat transfer and the air. 1.25 inches from the flowing water 2. Estimate the temperature change of the water as it moves through the 6-foot length of pipe. Hint: The mass flowrate of the water is: PAV, where is the average velocity of the pipe.

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.19P

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