Heat transfer Q3) The forming section of a plastics plant puts out a continuous sheet of plastic that is 1.2m wide and 2 mm thick at a rate of 15 m/min. The temperature of the plastic sheet is 90°Cwhen it is exposed to the surrounding air, and the sheet is subjected to air flow at 30°C at avelocity of 3 m/s on both sides along its surfaces normal to the direction of motion of thesheet. The width of the air cooling section is such that a fixed point on the plastic sheetpasses through that section in 2 s.Determine the rate of heat transfer30C, 3 msfrom the plastic sheet to the air.Plasticsheet15 mimin

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Q3) The forming section of a plastics plant puts out a continuous sheet of m wide and 2 mm thick at a rate of 15 m/min. The temperature of the pla when it is exposed to the surrounding air, and the sheet is subjected to air velocity of 3 m/s on both sides along its surfaces normal to the direction sheet. The width of the air cooling section is such that a fixed point on passes through that section in 2 s. Determine the rate of heat transfer Air 30°C, 3 ms

Q3) The forming section of a plastics plant puts out a continuous sheet of m wide and 2 mm thick at a rate of 15 m/min. The temperature of the pla when it is exposed to the surrounding air, and the sheet is subjected to air velocity of 3 m/s on both sides along its surfaces normal to the direction sheet. The width of the air cooling section is such that a fixed point on passes through that section in 2 s. Determine the rate of heat transfer Air 30°C, 3 ms

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.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.65P

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The forming section of a plastics plant puts out a continuous sheet of plastic that is 1.2 m wide and 2 mm thick at a rate of 15 m/min. The temperature of the plastic sheet is 90℃ when it is exposed to the surrounding air, and the sheet is subjected to air flow at 30℃ at a velocity of 3 m/s on both sides along its surfaces normal to the direction of motion of the sheet. The width of the air cooling section is such that a fixed point on the plastic sheet passes through that section in 2 s. Determine the rate of heat transfer from the plastic sheet to the air. (Answer: 437 W)
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