Homework problem for unsteady-state heat transferConsider a product to be sterilized if its coldest location during heating reaches 115°C. Considersterilization of potatoes where potatoes (4 cm diameter) is heated in steam at 121°C. Assumesymmetrical heating of potatoes and the heat transfer coefficient between the steam and thepotatoes is 20 W/m² K. The thermal diffusivity for potatoes is 1.5 × 107m²/s and the thermalconductivity is 0.4 W/m K. The potatoes are initially at 30°C.1) Calculate the heating time needed for sterilization.2) Calculate the temperature at the center of the potato after heating 1000 s and 2000 s. Plot howthe temperature at the center changes with time t.3) Calculate the temperature at the surface of the potato at 2000 s. Qualitatively plot how thetemperature changes across the apple at t = 2000 s.

To determine the heating time for sterlization, the temperature at the center of the potato after…

Homework problem for unsteady-state heat transfer Consider a product to be sterilized if its coldest location during heating reaches 115°C. Consider sterilization of potatoes where potatoes (4 cm diameter) is heated in steam at 121°C. Assume symmetrical heating of potatoes and the heat transfer coefficient between the steam and the potatoes is 20 W/m²K. The thermal diffusivity for potatoes is 1.5 x 107m²/s and the thermal conductivity is 0.4 W/m K. The potatoes are initially at 30°C. 1) Calculate the heating time needed for sterilization. 2) Calculate the temperature at the center of the potato after heating 1000 s and 2000 s. Plot how the temperature at the center changes with time t. 3) Calculate the temperature at the surface of the potato at 2000 s. Qualitatively plot how the temperature changes across the apple at t = 2000 s.

Homework problem for unsteady-state heat transfer Consider a product to be sterilized if its coldest location during heating reaches 115°C. Consider sterilization of potatoes where potatoes (4 cm diameter) is heated in steam at 121°C. Assume symmetrical heating of potatoes and the heat transfer coefficient between the steam and the potatoes is 20 W/m²K. The thermal diffusivity for potatoes is 1.5 x 107m²/s and the thermal conductivity is 0.4 W/m K. The potatoes are initially at 30°C. 1) Calculate the heating time needed for sterilization. 2) Calculate the temperature at the center of the potato after heating 1000 s and 2000 s. Plot how the temperature at the center changes with time t. 3) Calculate the temperature at the surface of the potato at 2000 s. Qualitatively plot how the temperature changes across the apple at t = 2000 s.

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.24P

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