The dynamics of dry spreading

The basic situation is illustrated in Fig. 3.2. The advancing fluid displays a certain dynamic contact angle 6, which depends on the contact line velocity U. Three separate experiments by Hoffmann, Marmur and Tanner indicate that for various liquids, and various solids, the relation between U and 0 is universal 

In typical conditions 0 = 10 S/y = 10 ) the angular correction iy0 amounts only to a very small fraction (10 ) of the main force S. It is thus very surprising that S does not show up in equation (10). 

---