Rock has often been suggested as a medium for the thermal storage of energy. A cylindrical piece of rock with diameter 10 m and height 20 m is used for the storage of thermal energy. The rock is insulated and has an average heat transfer coefficient, U = 0.28 kW/m2 K. The density of the rock material is 2,650 kg/m3 and its specific heat capacity is 0.72 kJ/kgK. The temperature of the rock is raised to 500C and the ambient temperature is 25C. Determine: a) The total energy stored in the rock in MWh. b) The temperature of the rock 12 h after the heating process

Rock has often been suggested as a medium for the thermal storage of energy. A cylindrical piece of rock with diameter 10 m and height 20 m is used for the storage of thermal energy. The rock is insulated and has an average heat transfer coefficient, U = 0.28 kW/m2 K. The density of the rock material is 2,650 kg/m3 and its specific heat capacity is 0.72 kJ/kgK. The temperature of the rock is raised to 500C and the ambient temperature is 25C. Determine: a) The total energy stored in the rock in MWh. b) The temperature of the rock 12 h after the heating process

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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