Problem 9-3: A T-type thermocouple is used to measure temperature differenceacross insulation in the ceiling of a residence in an energy monitoring program. Thetemperature difference across the insulation is used to calculate energy loss throughthe ceiling from the relationshipQ = k Ac (AT)whereAc = ceiling area =15 m²k=insulation thermal conductivity= 0.4Wm°CL= insulation thickness = 0.25 mAT = temperature difference = 5°CQ=heat loss (W)The value of the temperature difference is expected to be 5° C, and the thermocoupleemf is measured with an uncertainty of ±0.04 mV. Determine the required number ofthermopile junctions to yield an uncertainty in Q of ±5% (95%), assuming theuncertainty in all variables other than AT may be neglected.

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Answered: Problem 9-3: A T-type thermocouple is…

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.3DP

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