DRIFTSIM, A Program to Estimate Drift Distances of Spray Droplets

A BASIC language computer program (DRIFTSIM) was developed to rapidly estimate the mean drift distances of discrete sizes of water droplets discharged from atomizers on field sprayers. This program interpolates values from a large database of drift distances originally calculated with a flow simulation program (FLUENT). The simulations of drift distances up to 200 m (656 ft) included temperatures (10° to 30° C; 50° to 86° F), discharge heights (0 to 2.0 m; 0 to 6.56 ft), initial downward droplet velocities (0 to 50 m/s; 0 to 164 ft/s), relative humidities (10 to 100%), wind velocities (0 to 10.0 m/s; 0 to 32.8 ft/s), droplet sizes (10 to 2000 mm), and 20% turbulence intensity. The program requires about 15.5 Mb of disk space. Variables can be either in metric or English units and input can be either individual droplet sizes or size classes with portion of volume in each class.