Heat Transfer(Third year)2020- 2021Homework 01-03-2021ByDr. Basil Noori Merzahone-dimensional heat transfer and disregarding radiation, determine therate of heat transfer through the wall.Q4/ Steam at T01-320°C flows in a cast iron pipe (k=80W/m. C) whoseinner and outer diameters are D,=5cm, and D,-5.5cm, respectively. Thepipe is covered with 3 cm thick glass wool insulation withk=0.05W/m. C. Heat is lost to the surroundings at T2-5°C by naturalconvection and radiation, with a combined heat transfer coefficient to beh,=18W/m."C. Taking the heat transfer coefficient inside the pipe to be2 0h,-60W/m. C, determine the rate of heat loss from the steam per unitlength of the pipe. Also determine the temperature drops across the pipeshell and the insulation.Q5/ Determine the overall heat transfer coefficient U based on the outersurface of a D=2.5cm, and D =3.34 cm steel pipe (k=54.0W/m. C) forthe following conditions: inside and outside heat transfer coefficients are1200W/m".C. and 2000W/m.C respectively. If the temperature of innerfluid and outer fluid are 600°C and 300 C, calculate the heat transferthrough one meter length and the temperature of the outer surface.Q6/ A 5-m internal diameter spherical tank made of 1.5cm thick stainlesssteel (k=15W/m. C) is used to store iced water at 0'C. The tank is locatedin a room whose temperature is 20 C. Heat transfer between the outersurface of the tank and the surroundings is by natural convection only.The convection heat transfer coefficients at the inner and outer surfaces ofthe tank are 80W/m C and 10W/m."C, respectively. Determine the rateof heat transfer to the iced water in the tank and the amount of ice at 0°Cthat melts during a 24-h period. The heat of fusion of water atatmospheric pressure is h=333.7kJ/kgfg(2)

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Q4/ Steam at T1=320°C flows in a cast iron pipe (k=80W/m. C) whose inner and outer diameters are D,=5cm, and D,-5.5cm, respectively. The pipe is covered with 3 cm thick glass wool insulation with k=0.05W/m.C. Heat is lost to the surroundings at T2-5°C by natural convection and radiation, with a combined heat transfer coefficient to be 2o h,=18W/m. C. Taking the heat transfer coefficient inside the pipe to be h=60W/m.C, determine the rate of heat loss from the steam per unit 20 length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.

Q4/ Steam at T1=320°C flows in a cast iron pipe (k=80W/m. C) whose inner and outer diameters are D,=5cm, and D,-5.5cm, respectively. The pipe is covered with 3 cm thick glass wool insulation with k=0.05W/m.C. Heat is lost to the surroundings at T2-5°C by natural convection and radiation, with a combined heat transfer coefficient to be 2o h,=18W/m. C. Taking the heat transfer coefficient inside the pipe to be h=60W/m.C, determine the rate of heat loss from the steam per unit 20 length of the pipe. Also determine the temperature drops across the pipe shell and the insulation.

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.20P

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