Consider modeling a temperature sensor as a sphere having a thermal conductivity of 91 W/m-K, a density of 8900 kg/m³, and a specific heat of 444 J/kg-K. The sensor is in an environment where the heat transfer coefficient is 100 W/m2-K. Determine the maximum allowable diameter of the sensor if the 90% response time to a step-change in the fluid temperature, T∞, must be: • 10 second • 1 second . 0.01 second

Consider modeling a temperature sensor as a sphere having a thermal conductivity of 91 W/m-K, a density of 8900 kg/m³, and a specific heat of 444 J/kg-K. The sensor is in an environment where the heat transfer coefficient is 100 W/m2-K. Determine the maximum allowable diameter of the sensor if the 90% response time to a step-change in the fluid temperature, T∞, must be: • 10 second • 1 second . 0.01 second

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.9P: 3.9 The heat transfer coefficients for the flow of 26.6°C air over a sphere of 1.25 cm in diameter...

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