Drying-Induced Surface Roughening of Polymeric Coating Under Periodic Air Blowing

作者：Yamamura Masato^*; Uchinomiya Tetsuro; Mawatari Yoshihide; Kage Hiroyuki

来源：AICHE Journal, 2009, 55(7): 1648-1658.

DOI：10.1002/aic.11783

• drying
• liquid film coating
• marangoni flow
• surface roughness
• modeling

We carried out numerical simulations of drying-induced surface roughening of a moving liquid layer under periodic air blowing conditions. Using spatially non-uniform Biot number profiles along the coating surface, the solutions of coupled diffusion/heat transfer equations reveal a periodic growth and relaxation in concentration gradients in the vicinity of the liquid-gas interface. The resultant interfacial stress variations promote particular asymmetric surface topographies that grow and level in a sequential manner. The unique surface roughness is identified by considering time scales required for the web motion, the stress-induced sin-face evolution, and the pressure-driven leveling. Predicted drying maps represent the surface roughening behavior as regions in parameter space.

• 出版日期2009-7