5.10 A flaked cereal is of thickness 2L = 1.2 mm. The density, specific heat, and thermal conductivity of the flake are p = 700 kg/m³, cp = 2400 J/kg K, and k = 0.34 W/m.K, respectively. The product is to be baked by increasing its temperature from T₁ = 20°C to T = 220°C in a convec- tion oven, through which the product is carried on a con- veyor. If the oven is L = 3 m long and the convection heat transfer coefficient at the product surface and oven air temperature are h = 55 W/m² K and T. = 300°C, respectively, determine the required conveyor velocity, V. An engineer suggests that if the flake thickness is reduced to 2L = 1.0 mm the conveyor velocity can be increased, resulting in higher productivity. Determine the required conveyor velocity for the thinner flake.

5.10 A flaked cereal is of thickness 2L = 1.2 mm. The density, specific heat, and thermal conductivity of the flake are p = 700 kg/m³, cp = 2400 J/kg K, and k = 0.34 W/m.K, respectively. The product is to be baked by increasing its temperature from T₁ = 20°C to T = 220°C in a convec- tion oven, through which the product is carried on a con- veyor. If the oven is L = 3 m long and the convection heat transfer coefficient at the product surface and oven air temperature are h = 55 W/m² K and T. = 300°C, respectively, determine the required conveyor velocity, V. An engineer suggests that if the flake thickness is reduced to 2L = 1.0 mm the conveyor velocity can be increased, resulting in higher productivity. Determine the required conveyor velocity for the thinner flake.

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 8.35P

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