Validation of Two-Dimensional Droplet Deposition Models

Abstract

ABSTRACT AN open circuit windtunnel, a two-dimensional rec-tangular target, and a uniform droplet generator were used to obtain experimental data for comparison with an existing simulation model. Trajeactory data were obtained by using a camera to observe and record the path of the droplets as they approached the target. The distance the target had to be moved to find the top and bottom limiting trajectories was carefully measured and compared with the predicted values from the model. Four wind velocities and a range of droplet sizes from 113 to 338 jLtm were used in the experimental portion of this study. The two-dimensional simulation model showed good agreement with experimental data for velocities below 0.65 m/s. The two-dimensional model consistently over-predicted velocities above 1 m/s: i.e., for cell Reynolds numbers greater than 175. The amount of overprediction increased with increasing wind velocities. This error in prediction is attributed primarily to the relatively large cell size used to solve the Navier-Stokes equations for flow around a rectangular object.