The temperature of a experimental heated enclosure is being ramped up from 80 to 450°F at the rate of 20°F/min. A thermocouple, embedded in a Thermowell for protection, is being used to monitor the oven temperature. The thermocouple has a time constant of 6 s. ( a ) At t = 10 min, what is the difference between the actual temperature and the temperature indicated by the thermocouple? What is it at 60 min? ( b ) When the thermocouple indicates 450°F, the heater will begin to modulate and maintain the temperature at the desired 450°F. What is the actual oven temperature when the thermocouple first indicates 450°F?

The temperature of a experimental heated enclosure is being ramped up from 80 to 450°F at the rate of 20°F/min. A thermocouple, embedded in a Thermowell for protection, is being used to monitor the oven temperature. The thermocouple has a time constant of 6 s. ( a ) At t = 10 min, what is the difference between the actual temperature and the temperature indicated by the thermocouple? What is it at 60 min? ( b ) When the thermocouple indicates 450°F, the heater will begin to modulate and maintain the temperature at the desired 450°F. What is the actual oven temperature when the thermocouple first indicates 450°F?

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.2DP

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