화학공학소재연구정보센터
Chemical Engineering Science, Vol.58, No.11, 2245-2253, 2003
Measurement of liquid film thickness and the determination of spin-up radius on a rotating disc using an electrical resistance technique
A method of rapid measurement of liquid film thickness on a spinning disc surface is presented. The concepts used are based on the analysis of the electrical resistance of the liquid film and its relationship to film thickness when high frequency voltages are applied. A comparison with the Nusselt model is made for a wide range of operating conditions. Experimental data are presented and calculations of mean radial flow velocity based on film thickness measurements are made and shown to compare well with a simplified two-dimensional model. An empirical model for the extent of the spin-up radius is developed to provide a guide to the zone at which the Nusselt model breaks down. (C) 2003 Elsevier Science Ltd. All rights reserved.