A. The temperature of a gas stream is to be measured by a thermocouple whose junction can be approximated as a 1-mm- diameter sphere, as shown in the figure. The properties of the junction are k- 35 W/m °C, p38500 kg/m', and Cp= 320 J/kg °C, and the convection heat transfer coefficient between the junction and the gas is h=210 W/m? . °C. Determine how long it will take for the thermocouple to read 99 percent of the initial temperature difference.

A. The temperature of a gas stream is to be measured by a thermocouple whose junction can be approximated as a 1-mm- diameter sphere, as shown in the figure. The properties of the junction are k- 35 W/m °C, p38500 kg/m', and Cp= 320 J/kg °C, and the convection heat transfer coefficient between the junction and the gas is h=210 W/m? . °C. Determine how long it will take for the thermocouple to read 99 percent of the initial temperature difference.

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 8.8P

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