RAIN EROSION FOR ENGINE AIRFRAME COMPONENT TESTING

We propose to design and construct a sub-cale demonstration model of a water droplet generator for use in wind tunnel facilities such as those at the USAF Arnold Engineering Develoment Center. The innovative generator will include kilohertz-range stimulation to regularize the droplet size on the order of 1 - 2 millimeter diameter, enabling close experimental simulation of erosion due to high velocity rain impact on aircraft leading edge surfaces. Its design will allow variation of the characteristic droplet size, insertion velocity, and total flow rates to match a range of real meteorological conditions. The droplet generator will have multiple interchangeable nozzles with a range of exit aperture diameters and the capability to select the number of active nozzles for each experiment. The Phase I effort will include determination of the governing parameters for a simulation of erosive rain impact, design of a unique, innovative droplet generator, and demonstration of droplet production and control principles on a sub-scale basis.