Unique characteristics of biologically active materials such as fruits, vegetables, andother products require special care in handling. Following harvest and separationfrom producing plants, glucose is catabolized to produce carbon dioxide, watervapor, and heat, with attendant internal energy generation. Consider a single apple,spherical in shape, diameter 80 mm, which is ventilated with air at 5°C and h= 7.5W/m2.K. Within the apple thermal energy is uniformly generated at 4000.0J/kg.day.The density and thermal conductivity of the appleare 840 kg/m3 and 0.5 W/m.K.a. Derive anequation for temperature distribution inside the apple. Use theboundary conditions @r R, T = Ts, and @r=0, dT/dr 0. Ts is the surfacetemperature of sphere to be determined using convection equation.b. Determine the apple center and surface temperatures.

Calculate the surface temperature using the energy balance.

Answered: Unique characteristics of biologically…

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.8P

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