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.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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Heat Transfer