Answer correctly and quickly as possible please. To maximize production and minimize pumping costs, crude oil is heated to reduce its viscosity during transportation froma production field.(1) Consider a pipe-in-pipe configuration consisting of concentric steel tubes with an intervening insulating material. Theinner tube is used to transport warm crude oil through cold ocean water. The inner steel pipe (k, = 45 W/m-K) has aninside diameter of D = 150 mm and wall thickness t; = 20 mm while the outer steel pipe has an inside diameter ofDi2 = 250 mm and wall thickness I, = 1,. Determine the maximum allowable crude oil temperature to ensure thepolyurethane foam insulation (k, = 0.0425 Wim-K) between the two pipes does not exceed its maximum servicetemperature of Tp.max = 70°C. The ocean water is at T = -5°C and provides an external convection heat transfercoefficient of , = 500 W/m?-K. The convection coefficient associated with the flowing crude oil is h; = 450 W/m?-K.(2) It is proposed to enhance the performance of the pipe-in-pipe device by replacing a thin (t. = 10 mm) section ofpolyurethane located at the outside of the inner pipe with an aerogel insulation material (k, = 0.012 W/m-K). Determinethe maximum allowable crude oil temperature to ensure maximum polyurethane temperatures are below Tmax =70°C.Physical Properties Mathematical FunctionsDetermine the convection heat transfer resistance on the inside of the pipe per unit length, in m-K/W.m-K/WDetermine the conduction resistance of the polyurethane per unit length without the aerogel, in m-K/W.im-K/W%3!

R, convection i=1/hi*Ai =(1/450*π*0.150*1). L=1(unit length) =4.716*10^-3 =4.716mK/W

Determine the convection heat transfer resistance on the inside of the pipe per unit length, in m-K/W. m-K/W Determine the conduction resistance of the polyurethane per unit length without the aerogel, in m-K/W. Rconde m-K/W

Determine the convection heat transfer resistance on the inside of the pipe per unit length, in m-K/W. m-K/W Determine the conduction resistance of the polyurethane per unit length without the aerogel, in m-K/W. Rconde m-K/W

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 7.13P

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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…
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