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A long power transmission cable is buried at a depth(ground-to-cable-centerline distance) of 2 m. The cableis encased in a thin-walled pipe of 0.1-m diameter, and,to render the cable superconducting (with essentiallyzero power dissipation), the space between the cableand pipe is filled with liquid nitrogen at 77 K. Ifthe pipe is covered with a superinsulator
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Introduction to Heat Transfer
- I am struggling with this question. Part a and barrow_forwardMetals A and B were taken out from a boxed furnaces both at 500 degree Celsius. The ambient temperature, weher the metals were exposed is at 25 degree Celsius. It took 1 minute for Metal A to reach 100 degree Celsius. Determine the temperature of Metal B in degree Celsius, 2 minutes after it was tak out from the furnace to the new ambient temperature. It is known that ka= 2kb.arrow_forward3 • A piece of chromium steel of length 7.4cm (density= 8780kg/m³, k=50 W/m K) and specific heat capacity (C,=440 J/kg K) with mass 1.27 kg is rolled into a solid cylinder and heated to a temperature of 600 °C and quenched in oil at 36 °C. Show that the lumped capacitance system analysis is applicable and find the temperature of the cylinder after 4min. What is the total heat transfer during this period? You may take the convective heat transfer coefficient between the oil and cylinder at 280 W/m2K. delete home < backsac ock 7. home F enter 4.arrow_forward
- A piece of chromium steel of length 7.4 cm (density = 8780 kg/m^3; k = 50 w/mK and specific heat cp = 440j/kgK with mass 1.27 kg is rolled into a solid cylinder and heated to a temperature of 600 deg C and quenched in oil at 36 deg C. Show that the lumped capacitance system analysis is applicable and find the temperature of the cylinder after 4 min. What is the total heat transfer during the period? You may take the convective heat transfer coefficient between the oil and cylinder at 280 w/m^2 k.arrow_forwardA plane wall is 2m high and 3m wide and is 20cm thick. It is made of a material that has a thermal conductivity of 0.50W/m-K. A temperature difference of 60 degrees Celsius is imposed on the two large faces. Find the heat flux.arrow_forwardA wall in a house contains a single window. The window consists of a single pane of glass whose area is 0.13 m2 and whose thickness is 8 mm. Treat the wall as a slab of the insulating material Styrofoam whose area and thickness are 19 m2 and 0.10 m, respectively. Heat is lost via conduction through the wall and the window. The temperature difference between the inside and outside is the same for the wall and the window. Of the total heat lost by the wall and the window, what is the percentage lost by the window?arrow_forward
- Example: current of 200 A is passed through a stainless-steel wire [k = 19 W/m · ◦C] 3 mm in diameter. he resistivity of the steel may be taken as 70 μ · cm, and the length of the wire is 1 m. The ire is submerged in a liquid at 110 ◦C and experiences a convection heat-transfer coefficient of k W/m2 · ◦C. Calculate the center temperature of the wire.arrow_forwardEx1. A piece of chromium steel of length 7.4cm (density=8780kg/m³ ; k = 50w/mK and specific heat cp = 440j/kgK) with mass 1.27kg is rolled into a solid cylinder and heated to a temperature of 600°C and quenched in oil at 36°c. Show that the lumped capacitance system analysis is applicable and find the temperature of the cylinder after 4min. What is the total heat transfer during this period? You may take the convective heat transfer coefficient between the oil and cylinder at 280w/m2k.arrow_forward(3) A thick silver wire resistance heater measures 2 m in length with a diameter of 2.5 cm. The power output of the wire is 400 watts. If the maximum temperature in the wire is 800 K, what is the temperature of the wire at r = cm? 2 L=2m 0.75 • Q = Egen = 400 W wire d = 2.5cm = 0.025m R = 0.0125m Tmax=800k = T (r = 0) T(r = 0.0075m) = ? Rarrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning