Reconsider Prob. 7–39. Using the EES (or other) software, evaluate the effect of the sheet metal velocity on its surface temperature. By varying the sheet metal velocity from 3 to 30 m/s, plot the surface temperature of the sheet metal as a function of velocity. If the surface temperature of the sheet metal should be maintained above 100°C, determine the minimum velocity that is necessary to satisfy this condition. Evaluate the properties of air at 80°C.

Data from problem 39

A 5-m-long strip of sheet metal is being transported on a conveyor at a velocity of 5 m/s, while the coating on the upper surface is being cured by infrared lamps. The coating on the upper surface of the metal strip has an absorptivity of 0.6 and an emissivity of 0.7, while the surrounding ambient air temperature is 25°C. Radiation heat transfer occurs only on the upper surface, while convection heat transfer occurs on both upper and lower surfaces of the sheet metal. If the infrared lamps supply a constant heat flux of 5000 W/m², determine the surface temperature of the sheet metal. Evaluate the properties of air at 80°C.

Transcribed Image Text:

Infrared lamps - Sheet metal 5 m/s