Q1/Consider a compressed air pipe of length L= 4.5 m, inner diameter 7.4 cm, outer diameter 8 cm, and thermal conductivity k =14 W/m °C equipped with a 300-W strip heater. Air is flowing through the pipe at an average temperature of (- 8°C), and the average convection heat transfer coefficient on the inner surface is h= 30 W/m - °C. Assuming 10 percent of the heat generated in the strip heater is lost through the insulation, (a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the pipe, (b) obtain a relation for the variation of temperature in the pipe material by solving the differential equation, and (c) evaluate the outer surface temperature of the pipe.

Q1/Consider a compressed air pipe of length L= 4.5 m, inner diameter 7.4 cm, outer diameter 8 cm, and thermal conductivity k =14 W/m °C equipped with a 300-W strip heater. Air is flowing through the pipe at an average temperature of (- 8°C), and the average convection heat transfer coefficient on the inner surface is h= 30 W/m - °C. Assuming 10 percent of the heat generated in the strip heater is lost through the insulation, (a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the pipe, (b) obtain a relation for the variation of temperature in the pipe material by solving the differential equation, and (c) evaluate the outer surface temperature 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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.4P

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