초록 |
This study has focused on the frequency response method to investigate the sensitivity of the premetered coatingflowslike curtain and slot coatings. In curtain coating process, sensitivityhas beenscrutinized usingsimplifed 1-D viscocapillary model derived from 2-D curvilinear Navier-Stokes equations. To effectivelyanalyze the complex system of the frequency response equation,several novel computation methods havebeen suggested and compared: conventional method, two-shot method, and modal analysis. Also, effects ofprocess conditions on the sensitivity havebeen investigated. From the sensitivity results,it has been found that air pressure difference between top and bottom sides of the curtain makes the system more sensitive, leading to longer curtain trajectory. 1-D viscocapillary model has been derived In slot coating process, incorporated withpower-law fluids by combining Couette and Poiseuille flows coating bead region. It has been also confirmed that sensitivity resultsby 1-D models quantitatively agree with those by 2-D models and expeiments. |