Partially-frozen ice cream is being placed in a package before completion of the freezing process. The package has dimensions of 8 cm by 10 cm by 20 cm and is placed in air- blast freezing with convective heat coefficient of 50 W/(m2 K) for freezing. The product temperature is -5°C when placed in the package, and the air temperature is -25°C. The product density is 700 kg/m3, the thermal conductivity (frozen) is 1.2 W/(m K), and the specific heat of the frozen product is 1.9 kJ/(kg K). If the latent heat to be removed during blast freezing is 100 kJ/kg, estimate the freezing time.

Partially-frozen ice cream is being placed in a package before completion of the freezing process. The package has dimensions of 8 cm by 10 cm by 20 cm and is placed in air- blast freezing with convective heat coefficient of 50 W/(m2 K) for freezing. The product temperature is -5°C when placed in the package, and the air temperature is -25°C. The product density is 700 kg/m3, the thermal conductivity (frozen) is 1.2 W/(m K), and the specific heat of the frozen product is 1.9 kJ/(kg K). If the latent heat to be removed during blast freezing is 100 kJ/kg, estimate the freezing time.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.18P: The heat transfer coefficient for a gas flowing over a thin float plate 3-m long and 0.3-m wide...

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