In a slaughter house, 10-cm-thick meat slab initially at 15°C are to be cooled in the racks of a large freezer that is maintained at -12°C. The entire slab is to be cooled below 5°C, but the temperature of the meat slab is not to drop below -1°C anywhere during refrigeration to meet the poultry quality requirement. Considering the heat transfer from the 10-cm side edges of the slab to be negligible, a) evaluate if the lump capacitance method is applicable for the above cooling process, b) determine the heat transfer coefficient h that will enable us to meet both temperature constraints while keeping the refrigeration time to a minimum, and c) explain how the heat transfer coefficient in the freezer can be controlled. No calculation is required.

In a slaughter house, 10-cm-thick meat slab initially at 15°C are to be cooled in the racks of a large freezer that is maintained at -12°C. The entire slab is to be cooled below 5°C, but the temperature of the meat slab is not to drop below -1°C anywhere during refrigeration to meet the poultry quality requirement. Considering the heat transfer from the 10-cm side edges of the slab to be negligible, a) evaluate if the lump capacitance method is applicable for the above cooling process, b) determine the heat transfer coefficient h that will enable us to meet both temperature constraints while keeping the refrigeration time to a minimum, and c) explain how the heat transfer coefficient in the freezer can be controlled. No calculation is required.

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 3.15P: A thin-wall jacketed tank heated by condensing steam at one atmosphere contains 91 kg of agitated...

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