PROBE PARTICLES FOR IN-SITU DIRECT MEASUREMENT OF VORTICITY VECTORS

SCIENTISTS AT PHYSICAL SCIENCES, INC. HAVE DEVELOPED AN OPTICAL TECHNIQUE, KNOWN AS THE VORTICITY OPTICAL PROBE, OR VOP, FOR DIRECTLY MEASURING VORTICITY VECTORS IN WATER FLOWS. THE VORTICITY OPTICAL PROBE OPERATES BY SEEDING INTO LIQUID FLOW TRANSPARENT SPHERICAL PARTICLES THAT ARE TENS OF MICRONS IN DIAMETER WITH EACH CONTAINING ONE OR MORE EMBEDDED LEAD CARBONATE CRYSTALS THAT ACT AS PLANAR REFLECTORS OR "MIRRORS." RECENTLY, A TECHNIQUE HAS BEEN DEVELOPED FORMANUFACTURING THESE PROBE PARTICLES FROM ACRYLAMIDE GELS, FOR THE FIRST TIME ENABLING THEIR USE IN WATER FLOWS. HOWEVER, THE CURRENT GEL PARTICLE PRODUCTION TECHNIQUE PERMITS SIMPLE MANUFACTURE OF ONLY SMALL QUANTITIES. TO SEED A FLOW THAT WOULD BE OF INTEREST TO DARPA, A DEVICE FOR MASS PRODUCING THE PROBE PARTICLES IS NEEDED. DEVELOPEMENT OF THIS DEVICE IS PROPOSED HEREIN. ANTICIPATED BENEFITS/POTENTIAL COMMERCIAL APPLICATIONS - THIS ADVANCED DEVELOPMENT EFFORT WILL ESTABLISH THE FEASIBILITY OF APPLYING THE VOP TO STUDIES OF CRITICAL FLOWFIELDS IN WATER TUNNELS OR AROUND TEST VEHICLES. IT WILL LAY THE FOUNDATION FOR A PHASE II EFFORT WHEREIN A COMPLETE VOP INSTRUMENT WILL BE USED TOACQUIRE DATA IN A FLOWFIELD OF INTEREST TO DARPA. SUCCESS IN PHASE II WILL DEMONSTRATE TO THE FLUID DYNAMICS COMMUNITY THAT THE VOP IS AN INVALUABLE NEW MEASUREMENT TECHNIQUE, THEREBY ESTABLISHING A BASIS FORCOMMERCIAL SALES OF INSTRUMENTS AND PROBE PARTICLES TO OTHER LABORATORIES WORLDWIDE.