ARS | Publication request: WIND TUNNEL TESTING AND COMPARISON OF THREE SALTATION IMPACT SENSORS

Submitted to: International Conference on Aeolian Research
Publication Type: Abstract Only
Publication Acceptance Date: June 7, 2006
Publication Date: July 24, 2006
Citation: Van Pelt, R.S., Zobeck, T.M., Peters, P., Visser, S. 2006. Wind tunnel testing and comparison of three saltation impact sensors. International Conference on Aeolian Research. July 24 - 28, 2006, Guelph, Ontario, Canada.

Technical Abstract: Saltation impact sensors are used to investigate the temporal and spatial fluctuations of saltation intensity over eroding surfaces. Three types of impact sensors have been used by various researchers; the Saltiphone, the Sensit, and the Safire. In spite of the wide-spread use of these devices by the international research community, little is known about how to share and compare data collected with the various sensors. We initiated this investigation as collaboration between the USDA-ARS Wind Erosion and Water Conservation Research Unit and the Erosion, Soil and Water Conservation Group at Wageningen University in the Netherlands to find the limitations of these sensors and to try to develop correction coefficients that will allow exchange of data among researchers. We tested four each of the Saltiphone, Sensit, and Safire impact sensors at 5 cm above a sandpaper surface in the center of a wind tunnel approximately 2 m downwind from calibrated saltation particle drop tubes. Wind velocities of 7, 10, and 14.7 m s-1 were used and glass bead diameter classes of 53 – 75, 75 – 105, 105 – 125, 150 – 210, 210 – 250, and 297 – 420 'm. None of the sensors is effective at detecting impacts from particles smaller than about 75 'm in diameter. Other than the effects of different sensor impact areas, the Saltiphone and Sensit are approximately equally sensitive for larger particle diameters. The Safire was the least sensitive and most variable in all cases. Large variability among similar sensors limits their usefulness in determining and quantifying saltation intensity.