A pipe with 8 cm internal diameter, 9 cm outer diameter, 2 meter long, thermal conductivity 30W/mK is insulated by glass wool material with which thermal conductivity 0,05W/mK, thickness 4 cm. Internal surface temperature of the pipe T₁ is 80°C, surrounding temperature where pipe is located is 20°C, convection heat transfer constant on outer surface of insulation is 25W/m²K. Kp 30W/mK T.= 20 °C h. = 25W/m²K 4cm K = 0,05W/mK a. Determine the heat loss from the pipe to surrounding (W)? b. What is temperature of the surface between glass wooden and pipe (T2)? c. What is critical insulation radius for pipe? Is insulation on the pipe succesful? Explain

A pipe with 8 cm internal diameter, 9 cm outer diameter, 2 meter long, thermal conductivity 30W/mK is insulated by glass wool material with which thermal conductivity 0,05W/mK, thickness 4 cm. Internal surface temperature of the pipe T₁ is 80°C, surrounding temperature where pipe is located is 20°C, convection heat transfer constant on outer surface of insulation is 25W/m²K. Kp 30W/mK T.= 20 °C h. = 25W/m²K 4cm K = 0,05W/mK a. Determine the heat loss from the pipe to surrounding (W)? b. What is temperature of the surface between glass wooden and pipe (T2)? c. What is critical insulation radius for pipe? Is insulation on the pipe succesful? Explain

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.10P: 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the...

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