Case of Motionless Air at Room Temperature in Turbulent Mode

2 Case of Motionless Air at Room Temperature in Turbulent Mode 

FIGURE 2.4 Profiles of temperature developed through the thickness of a rubber sheet at various times (min), when the rubber sheet initially at 160°C is cooled down in motionless air at 20°C. Thickness = 1 cm. Free convection is in laminar mode. Half the thickness is shown. 

the equation expressing the boundary at the rubber-air interface becomes  

In the same way as for the previous case, the problem is resolved using a numerical treatment. 

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