Pattern thermal gradient-induced

Electrohydrodynamic patterning/Thermal-gradient induced surface patterning. A stable liquid polymer film becomes unstable when the surface tension is overcome... 

From the results of RTD studies it can be concluded that small changes in bowl temperatures above or below the feed temperature have a significant effect on flow patterns in the bowl. This result supports the hypothesis that thermally induced density gradients lead to mixing currents. In addition to temperature, flow patterns are affected by feed flow rate and bowl speed. Separation efficiency and classification studies show that the various flow patterns produced under different operating conditions affect separation performance in both types of separations studied. This fact leads to the conclusion that flow patterns must be better understood and controlled in order to optimize classification of superfine solids. 

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