Evolution of wetting radius during centrifugal spreading of polydimethylsiloxane drop over rotating glass substrate (spin coating). The spin coating is a popular thin film coating production method in electronics industry. PDMS4 - glass table rotates at 300 rpm; PDMS5 - glass table rotates at 600 rpm. Time is normalized by characteristic time scale; wetting radius is normalized by initial wetting radius. Dots - experiment [Ref 1], curves - FLUENT prediction.

Comparison of wetting radius vs. time for PDMS4 (black) and PDMS5 (red) experiments. Time is scaled by appropriate time scales (12.62 sec for PDMS4 and 3.6 sec for PDMS5). Radius is scaled by initial radius. Dots - experiment (Reference 1).

Reference 1: N. Fraysse, G. M. Homsy "An experimental study of rivulet instabilities in centrifugal spin coating of viscous Newtonian and non-Newtonian fluids", 1994, Phys. Fluids, 6 (4), pp 1491-1504.