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 °C when it is exposed to the surrounding air, and the sheet is subjected to airflow at 30 °C at a velocity of 2 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 5 s. Draw the neat figure of the setup and determine the rate of heat transfer from the plastic sheet to the air.

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 °C when it is exposed to the surrounding air, and the sheet is subjected to airflow at 30 °C at a velocity of 2 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 5 s. Draw the neat figure of the setup and determine the rate of heat transfer from the plastic sheet to the air.

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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