To ensure effective heat transfer from the food inside a freezer, the 2-mm thick layer of frost thatformed at its inside surface must be melted. If the compartment is in ambient air at 20°C and acoefficient of h = 2-Wcharacterizes heat transfer by natural convection from the exposed surface ofm2-Kthe layer, how long will it take for the entire layer of frost to melt in seconds if it is initially at 0°C? Thefrost has a density of 700 and a latent heat of fusion of 334m3kJkg'

Answered: Image /qna-images/answer/b173d2fe-5418-455d-91fc-7dd8b71df6cd.jpg

Answered: To ensure effective heat transfer from…

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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A food product with 73% moisture content is being frozen in a 7 cm-diameter can. The product density is 970 kg/m³, the thermal conductivity is 1.2 W/(m K), and the initial freezing temperature is -2.5°C. After 11 hour in the -40°C freezing medium, the product temperature is -10°C. Estimate the convective heat-transfer coefficient for the freezing medium. Assume the can has infinite height. a. h = ... W/m² K
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A 20-cm diameter sphere has a surface temperature of 500 K. The sphere is suspended in 300 K still air. Find the heat transfer from the sphere. Neglect Radiation. (To find the heat transfer coefficient use Nusselt numbers) use properties of air at 300 K
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