A 15 cm-OD pipe is buried with its centerline 1.25 m below the surface of the ground [k of soil is 0.35 W/(m K)]. An oil having a density of 800 kg/m³ and a specific heat of 2.1 kJ/(kg K) flows in the pipe at 5.6 L/s. Assuming a ground surface temperature of 5°C and a pipe wall temperature of 95°C, estimate the length of pipe in which the oil temperature decreases by 5.5°C. + Tε = 5ºC Z= 1.25 m D= 15 cm 7p=95°C

A 15 cm-OD pipe is buried with its centerline 1.25 m below the surface of the ground [k of soil is 0.35 W/(m K)]. An oil having a density of 800 kg/m³ and a specific heat of 2.1 kJ/(kg K) flows in the pipe at 5.6 L/s. Assuming a ground surface temperature of 5°C and a pipe wall temperature of 95°C, estimate the length of pipe in which the oil temperature decreases by 5.5°C. + Tε = 5ºC Z= 1.25 m D= 15 cm 7p=95°C

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 7.27P

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