A carton (50 cm x 30 cm x 85 cm) of milk, initially at 23°C, was placed in a refrigerator with the thermostat set to 4°C. After 3 hours, the temperature of the milk dropped by 3.6°C. Using the lumped systems analysis, estimate the heat transfer coefficient for the cooling of milk in the refrigerator given the following properties of milk: Density: 1035 kg/m³ Specific heat capacity: 3930 J/kg K Thermal conductivity: 0.278 W/m K Explain why the lumped system analysis is applicable in this situation.

A carton (50 cm x 30 cm x 85 cm) of milk, initially at 23°C, was placed in a refrigerator with the thermostat set to 4°C. After 3 hours, the temperature of the milk dropped by 3.6°C. Using the lumped systems analysis, estimate the heat transfer coefficient for the cooling of milk in the refrigerator given the following properties of milk: Density: 1035 kg/m³ Specific heat capacity: 3930 J/kg K Thermal conductivity: 0.278 W/m K Explain why the lumped system analysis is applicable in this situation.

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.37P

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