Consider a thin suspended hotplate that measures 0.4 mx 0.4 m. The isothermal plate has a mass of 3.75 kg, a specific heat of 2770 J/kg-K, and a temperature of 200°C. The ambient air temperature is 25°C and the surroundings temperature is 25°C. If the convection coefficient is 6.4 W/m²-K and the emissivity of the plate is & = 0.42, determine the time rate of change of the plate temperature, dT/dt, when the plate temperature is 200°C. Evaluate the magnitude of the heat losses by convection and by radiation. dT/dt = i gradl= = i conv= i K/s W W

Consider a thin suspended hotplate that measures 0.4 mx 0.4 m. The isothermal plate has a mass of 3.75 kg, a specific heat of 2770 J/kg-K, and a temperature of 200°C. The ambient air temperature is 25°C and the surroundings temperature is 25°C. If the convection coefficient is 6.4 W/m²-K and the emissivity of the plate is & = 0.42, determine the time rate of change of the plate temperature, dT/dt, when the plate temperature is 200°C. Evaluate the magnitude of the heat losses by convection and by radiation. dT/dt = i gradl= = i conv= i K/s W W

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 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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