An 5-m·internal-diameter spherical tank made of 1.5-cm-thick stainless steel (k = 15 W/m·C) is used to störe iced water at 0°C. The tank is located in a room whose temperature is 30°C. The walls of the room are also at 30°C. The outer surface of the tank is gray (emissivity e = 0.9), and heat transfer between the outer surface of the tank and the surroundings is by natural convection and radiation. The convection heat transfer coefficients at the inner and the outer surfaces of the tank are 80 W/m2·C and 10 W/m2·C, respectively. Determine the amount of ice at 0°C that melts during a 24-h period. The heat of fusion of water at atmospheric pressure is hif = 333.7 kJ/kg.

An 5-m·internal-diameter spherical tank made of 1.5-cm-thick stainless steel (k = 15 W/m·C) is used to störe iced water at 0°C. The tank is located in a room whose temperature is 30°C. The walls of the room are also at 30°C. The outer surface of the tank is gray (emissivity e = 0.9), and heat transfer between the outer surface of the tank and the surroundings is by natural convection and radiation. The convection heat transfer coefficients at the inner and the outer surfaces of the tank are 80 W/m2·C and 10 W/m2·C, respectively. Determine the amount of ice at 0°C that melts during a 24-h period. The heat of fusion of water at atmospheric pressure is hif = 333.7 kJ/kg.

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 8.33P

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