10 hot rods (L = 5 m and d = 2 cm) are buried in the ground parallel to each other each rod is 10 cm apart and at a depth 3 m from the ground surface. The thermal conductivity of the soil is 0.6 W/m K. If the surface temperature of the rods and the ground are 600 K and 30 °C, respectively. Draw the figure and determine the rate of heat transfer from the fuel rods to the atmosphere through the soil

10 hot rods (L = 5 m and d = 2 cm) are buried in the ground parallel to each other each rod is 10 cm apart and at a depth 3 m from the ground surface. The thermal conductivity of the soil is 0.6 W/m K. If the surface temperature of the rods and the ground are 600 K and 30 °C, respectively. Draw the figure and determine the rate of heat transfer from the fuel rods to the atmosphere through the soil

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 2.60P

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3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the convection heat transfer coefficient between the outer surface of the container and the air is 6.8 , the temperature of the air is 27°C, and the temperature of the surface of the sphere is –183°C, determine the rate of heat transfer by convection.
1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.
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