A flat cereal has a thickness of 2L =1.2mm. The specific mass, specific heat and thermal conductivity of the cereal are, respectively, 700 Kg/m³ and 0.34 W/m*K. The product must be baked, raising its temperature from 20°C to 220°C , in a convective oven with a 3-meter-long conveyor belt. The convection heat transfer coefficient is 55 W/K*m? and its temperature is 300 °C. Determine: a) Is the global capacitance hypothesis valid? b) What speed is needed for the treadmill? c) An engineer suggests that if the grain thickness is reduced to 2L=1mm, the belt speed can be increased, resulting in higher productivity. What would the belt speed be for this new grain thickness?

A flat cereal has a thickness of 2L =1.2mm. The specific mass, specific heat and thermal conductivity of the cereal are, respectively, 700 Kg/m³ and 0.34 W/mK. The product must be baked, raising its temperature from 20°C to 220°C , in a convective oven with a 3-meter-long conveyor belt. The convection heat transfer coefficient is 55 W/Km? and its temperature is 300 °C. Determine: a) Is the global capacitance hypothesis valid? b) What speed is needed for the treadmill? c) An engineer suggests that if the grain thickness is reduced to 2L=1mm, the belt speed can be increased, resulting in higher productivity. What would the belt speed be for this new grain thickness?

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 3.10P: 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the...

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