A steel tube carries steam at a temperature of 320°C. A thermometer pocket of iron (k = 52.3W/mK) of inside diameter 15 mm and 1 mm thick is used to measure the temperature. The error to be tolerated is 1.5% of maximum. Estimate the length of the pocket necessary to measure the temperature within this error. The diameter of the steel tube is 95 mm. Assume h = 93 W/m2 K and the tube wall temperature is 120°C. Suggest a suitable method of locating the thermometer pocket.

A steel tube carries steam at a temperature of 320°C. A thermometer pocket of iron (k = 52.3W/mK) of inside diameter 15 mm and 1 mm thick is used to measure the temperature. The error to be tolerated is 1.5% of maximum. Estimate the length of the pocket necessary to measure the temperature within this error. The diameter of the steel tube is 95 mm. Assume h = 93 W/m2 K and the tube wall temperature is 120°C. Suggest a suitable method of locating the thermometer pocket.

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 6.21P

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