A heavy-water-cooled research reáctor is fueled with natural- Im metal rods 0.9 in. in diameter clad with 0.05-in.-thick aluminum. The maximum temperature in the fuel at a certain cross section in the rod is 700°F. The coolant bulk temperature at the cross section is 180°F. The heat-transfer coefficient is 5000 Btu/hr ft2 °F. Determine for the above cross section (a) the neutron flux (thermal); (b) the specific power, kw/kg fuel; (c) the maximum cladding temperature; (d) the maximum coolant temperature; (e) the minimum coolant pressure to avoid boiling; and (f) the theoretical maximum flux beyond which the above maximum fuel

A heavy-water-cooled research reáctor is fueled with natural- Im metal rods 0.9 in. in diameter clad with 0.05-in.-thick aluminum. The maximum temperature in the fuel at a certain cross section in the rod is 700°F. The coolant bulk temperature at the cross section is 180°F. The heat-transfer coefficient is 5000 Btu/hr ft2 °F. Determine for the above cross section (a) the neutron flux (thermal); (b) the specific power, kw/kg fuel; (c) the maximum cladding temperature; (d) the maximum coolant temperature; (e) the minimum coolant pressure to avoid boiling; and (f) the theoretical maximum flux beyond which the above maximum fuel

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.37P

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To maximize production and minimize pumping costs, crude oil is heated to reduce its viscosity during transportation from a production field. (1) Consider a pipe-in-pipe configuration consisting of concentric steel tubes with an intervening insulating material. The inner tube is used to transport warm crude oil through cold ocean water. The inner steel pipe (ks= 40 W/m·K) has an inside diameter of Di, 1= 150 mm and wall thickness ti= 20 mm while the outer steel pipe has an inside diameter of Di, 2= 250 mm and wall thickness to=ti. Determine the maximum allowable crude oil temperature to ensure the polyurethane foam insulation (kp= 0.0675 W/m·K) between the two pipes does not exceed its maximum service temperature of Tp, max= 70°C. The ocean water is at ∞ T∞, o= -5°C and provides an external convection heat transfer coefficient of ho= 500 W/m2·K. The convection coefficient associated with the flowing crude oil is hi= 450 W/m2·K. (2) It is proposed to enhance the performance of the…
To maximize production and minimize pumping costs, crude oil is heated to reduce its viscosity during transportation from a production field. (1) Consider a pipe-in-pipe configuration consisting of concentric steel tubes with an intervening insulating material. The inner tube is used to transport warm crude oil through cold ocean water. The inner steel pipe (ks= 40 W/m·K) has an inside diameter of Di, 1= 150 mm and wall thickness ti= 20 mm while the outer steel pipe has an inside diameter of Di, 2= 250 mm and wall thickness to=ti. Determine the maximum allowable crude oil temperature to ensure the polyurethane foam insulation (kp= 0.0675 W/m·K) between the two pipes does not exceed its maximum service temperature of Tp, max= 70°C. The ocean water is at ∞ T∞, o= -5°C and provides an external convection heat transfer coefficient of ho= 500 W/m2·K. The convection coefficient associated with the flowing crude oil is hi= 450 W/m2·K. (2) It is proposed to enhance the performance of the…
2.51 Determine by means of a flux plot the temperatures and heat flow per unit depth in the ribbed insulation shown in the accompanying sketch.
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The author and his then 6-year-old son have conducted the following experiment to determine the thermal conductivity of a hot dog. They first boiled water in a large pan and measured the temperature of the boiling water to be 94°C, which is not surprising, since they live at an elevation of about 1650 m in Reno, Nevada. They then took a hot dog that is 12.5 cm long and 2.2 cm in diameter and inserted a thermocouple into the midpoint of the hot dog and another thermocouple just under the skin. They waited until both thermocouples read 20°C, which is the ambient temperature. They then dropped the hot dog into boiling water and observed the changes in both temperatures. Exactly 2 min after the hot dog was dropped into the boiling water, they recorded the center and the surface temperatures to be 59°C and 88°C, respectively. The density of the hot dog can be taken to be 980 kg/m3, which is slightly less than the density of water, since the hot dog was observed to be floating in water while…
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