V-22 Three-Dimensional (3D) Downwash Measurement Navy SBIR FY2009.1 Sol No.: Navy SBIR FY2009.1 Topic No.: N091-029 Topic Title: V-22 Three-Dimensional (3D) Downwash Measurement Proposal No.: N091-029-1314 Firm: Science and Engineering Services, Inc. 6992 Columbia Gateway Drive Suite 200 Columbia, Maryland 21046-2986 Contact: Anand Radhakrishnan Phone: (443) 539-3102 Web Site: http://www.sesi-md.com Abstract: Science and Engineering Services. Inc. (SESI) proposes to develop an Aerosol Lidar Velocimeter (ALV) to obtain concurrent three-component wind velocity measurements in the downwash of a rotorcraft operating in shipboard environments. We propose to use a multi-beam lidar system to obtain aerosol backscatter data from the flowfield and to develop a time-lag cross-correlation algorithm to extract three-component velocity measurements. In Phase I, a breadboard prototype will be designed and built to demonstrate proof-of-concept of obtaining velocity measurements from a representative flowfield and the results will be validated using sonic and cup-and-vane anemometers. This breadboard will be used to benchmark the system requirements for the design of an ALV prototype that, in Phase II, will be built and tested on a land-based full-scale test bed, with a helicopter hovering near a vertical face, subject to availability of aircraft. These measurements will be validated by comparing with anemometers and existing test data, along with computational predictions. Benefits: The benefits of an Aerosol Lidar Velocimeter are that: a non-intrusive system will not interfere with flowfield; an aerosol lidar can be used for both day-time and night-time operations; no flow seeding is required unlike other non-intrusive methods such as PIV, LDV, etc; and it is relatively inexpensive compared to existing flow sensors. A non-intrusive velocimetry system for obtaining concurrent measurements has several commercial applications such as wind tunnel sensors, wind turbine flow survey equipment, sniper and ballistic targeting systems, analyzing the effect of rotor downwash on personnel and equipment at airports, offshore installations and building helipads, as well as measuring the flowfield in the vicinity of buildings and other structures, among others. Return