A simple low-cost sand catcher for wind-tunnel simulations

A simple low-cost sand catcher has been developed for use in wind-tunnel experiments. It is 500 mm high with a 300 mm by 20 mm inlet opening, and is designed to measure total mass transport directly. The length is 280 mm and its walls slowly expand at an angle of 5.6degrees. The top view is similar to that of the widely used BSNE sampler. Each sidewall is vented with three ventilation screens. Two sets of experiments were conducted on dune sand and at different wind velocities to investigate to what degree the catcher samples isokinetically, efficiently and non-selectively. The results indicate that the catcher measures sufficiently isokinetically (inlet wind velocity over outside wind velocity >0.9). Catch efficiency was around 0.75 and the degree of non-selectivity was >0.80 for 95 per cent of the particle sizes of the test material. It was also observed that the influence of wind velocity on the tested sampler characteristics was of minor importance so that no specific corrections need to be made for different wind velocities. Copyright (C) 2003 John Wiley Sons, Ltd.