An experiment was conducted to determine surface convective heat transfer coefficient for peas being frozen in an air-blast freezer. For this purpose, a metal analog of peas was used. The analog was a solid copper ball with a diameter of 1 cm. A small hole was drilled to the center of the copper ball, and a thermocouple junction was located at the center using a high-conductivity epoxy. The density of copper is 8954 kg/m³, and its specific heat is 3830 J/(kg K). The copper ball (at a uniform initial temperature of 10 ºC) was hung in the path of air flow (at -40 °C) and the center temperature indicated by the thermocouple was recorded. The following table lists the temperature at 1-min intervals for 14 min. Determine the surface heat transfer coefficient from these data.

An experiment was conducted to determine surface convective heat transfer coefficient for peas being frozen in an air-blast freezer. For this purpose, a metal analog of peas was used. The analog was a solid copper ball with a diameter of 1 cm. A small hole was drilled to the center of the copper ball, and a thermocouple junction was located at the center using a high-conductivity epoxy. The density of copper is 8954 kg/m³, and its specific heat is 3830 J/(kg K). The copper ball (at a uniform initial temperature of 10 ºC) was hung in the path of air flow (at -40 °C) and the center temperature indicated by the thermocouple was recorded. The following table lists the temperature at 1-min intervals for 14 min. Determine the surface heat transfer coefficient from these data.

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 9.15P

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