EES Metal plates (k = 180 W/m-K, p= 2800 kg/m², |and c, = 880 J/kg-K) with a length of 1 m and a thickness of 2 cm exiting an oven are then conveyed through a 10-m-long cooling chamber at a speed of 5 mm/s. The plates enter the cooling chamber at an initial temperature of 155°C. In the cooling chamber, the plates are cooled with 10°C air blowing in parallel over them. To prevent any incident of ther- mal burn, it is necessary to design the cooling process such that the plates exit the cooling chamber at a relatively safe 7-50 PtD temperature. Determine the air velocity such that the temperature of the plates exiting the cooling chamber is 45°c or less. Assume combined laminar and turbulent flow (verify this assumption). Hint: Use the lumped system analysis to determine the required cooling time (verify application of this method to this problem). Cooling chamber 5 mm/s 2 cm Metal plate Blowing air, 10°C

EES Metal plates (k = 180 W/m-K, p= 2800 kg/m², |and c, = 880 J/kg-K) with a length of 1 m and a thickness of 2 cm exiting an oven are then conveyed through a 10-m-long cooling chamber at a speed of 5 mm/s. The plates enter the cooling chamber at an initial temperature of 155°C. In the cooling chamber, the plates are cooled with 10°C air blowing in parallel over them. To prevent any incident of ther- mal burn, it is necessary to design the cooling process such that the plates exit the cooling chamber at a relatively safe 7-50 PtD temperature. Determine the air velocity such that the temperature of the plates exiting the cooling chamber is 45°c or less. Assume combined laminar and turbulent flow (verify this assumption). Hint: Use the lumped system analysis to determine the required cooling time (verify application of this method to this problem). Cooling chamber 5 mm/s 2 cm Metal plate Blowing air, 10°C

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.4P

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