3. A 25 m length of pipe is used to transport steam from the boiler to...

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3. A 25 m length of pipe is used to transport steam from the boiler to the turbine in a Rankine cycle power plant. The pipe is 2.0 m in diameter and its surface temperature is 450C. Energy is lost from the pipe to the surroundings due to heat transfer by convection. The convection coefficient between the pipe and the surrounding air is 8 W/mK and the air temperature is 15C. The radiation portion of the heat transfer can be treated as emission from a grey body to an enclosure. The enclosure temperature (i.e. the surfaces formed by the power plant containing the pipe and turbine) can be taken as 10C. The emissivity of the surface of the pipe is 0.10. The system can be considered to be at steady-state. Calculate the total rate of energy transfer from the pipe to the surroundings due to convective heat transfer and due to radiation heat transfer, in MW. 3. A 25 m length of pipe is used to transport steam from the boiler to the turbine in a Rankine cycle power plant. The pipe is 2.0 m in diameter and its surface temperature is 450C. Energy is lost from the pipe to the surroundings due to heat transfer by convection. The convection coefficient between the pipe and the surrounding air is 8 W/mK and the air temperature is 15C. The radiation portion of the heat transfer can be treated as emission from a grey body to an enclosure. The enclosure temperature (i.e. the surfaces formed by the power plant containing the pipe and turbine) can be taken as 10C. The emissivity of the surface of the pipe is 0.10. The system can be considered to be at steady-state. Calculate the total rate of energy transfer from the pipe to the surroundings due to convective heat transfer and due to radiation heat transfer, in MW.