Oil whose temperature is 30°C is flowed through a pipe with a diameter of 50 cm. The pipe is in an environment where the temperature is 20°C. So that not a lot of heat comes out of the pipe, the pipe is wrapped with an insulating material (k = 0.007 W/mK) as thick as 5 cm. If the convection coefficient of the outer surface of the pipe is 12 W/m²K, calculate the heat flow from the pipe per meter of length

Oil whose temperature is 30°C is flowed through a pipe with a diameter of 50 cm. The pipe is in an environment where the temperature is 20°C. So that not a lot of heat comes out of the pipe, the pipe is wrapped with an insulating material (k = 0.007 W/mK) as thick as 5 cm. If the convection coefficient of the outer surface of the pipe is 12 W/m²K, calculate the heat flow from the pipe per meter of length

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.38P: 2.38 The addition of aluminum fins has been suggested to increase the rate of heat dissipation from...

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Consider a steam pipe of length 15 ft, inner radius 2 in., outer radius 2.4 in., and thermal conductivity 7.2 Btu/hr-ft-°F. Steam is flowing through the pipe at an average temperature of 250°F, and the average convection heat transfer coefficient on the inner surface is given to be 1.25 Btu/hr-ft2-°F. If the average temperature on the outer surfaces of the pipe is 160°F, determine the rate of heat loss from the steam through the pipe. ANSWER:______Btu/hr
There are 3 windows in a room with a width of 100 cm and a height of 150 cm.There is a single glass (k=0. 9 W/mK) of 5 mm thickness in the windows initially. Instead of these glasses to save heatYou are considering replacing it with double glazing consisting of 5 mm glass and 12 mm air (k=0.022 W/mK). Indoor and outdoor environmenttemperatures are 20 0C and -10 0C, respectively, and the heat transfer coefficients are 7 W/m2 K and 25 W/m2 K. The total heat loss in the room is 3.5 kW.when switching to double glazing;a) Find the decrease in heat transfer. b) Considering that the heat given by the heaters remains 3.5 kW, what would the room temperature be?
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