Marine Skin Friction and Turbulence Measurements Using Doppler Optical Coherence Tomography Navy SBIR FY2010.1 Sol No.: Navy SBIR FY2010.1 Topic No.: N101-098 Topic Title: Marine Skin Friction and Turbulence Measurements Using Doppler Optical Coherence Tomography Proposal No.: N101-098-0521 Firm: Physical Sciences Inc. 20 New England Business Center Andover, Massachusetts 01810-1077 Contact: Hartmut Legner Phone: (978) 689-0003 Web Site: http://www.psicorp.com Abstract: Physical Sciences Inc. (PSI) proposes to develop and demonstrate a novel, non-obtrusive system based on a Fourier Domain Doppler Coherent Optical Tomography (FD-DOCT) technique to measure the near-wall fluid velocity profile, skin friction and turbulence characteristics present in high Reynolds number fluid flow. This system will allow fluid velocity profile measurement with high spatial resolution (5 microns) in the 5 to 100 micron region of the wall/fluid boundary and thus provide direct information on wall shear stress, a quantity of paramount interest to researchers in their efforts to understand turbulent flow and its contribution to drag resistance for submarines and ships. The spatial resolution of this technique, combined with its speed of measurement and ability to function in highly turbulent flows, will exceed those of the traditional techniques for flow field measurements such as Hot Wire Anemometry, LDV and PIV, and for shear stress measurements using direct or inferred schemes. This improved accuracy will translate into a better understanding of Reynolds number scaling, improved CFD validation, and submarine/ship configuration design. We have already performed proof-of-principle experiments that demonstrated the ability of FD-DOCT to make fluid flow measurements in a water flow environment. Benefits: The measurement of space and time-resolved, shear-stress fluctuations, in the immediate proximity of the hull walls of submarines and ships is of vital importance to the naval engineering community because of its considerable impact on marine system performance and the economics of marine transportation. Such data can provide physical insight into complex flow phenomena, including turbulent viscous drag, transition to turbulence, and flow separations. It will also be capable of assessing new drag reduction techniques for Naval vessels and submarines. This will lead to lower fuel costs and faster marine vehicles. The difficulty in performing accurate highly localized measurements, especially in the region that lies within tens of microns from the wall surface, has generated a host of different technologies, none of which are entirely satisfactory. The proposed FD-DOCT will satisfy an unmet scientific and commercial need for both increased measurement precision and new understanding of complex flow physics. The users of such data include the Naval engineering community, NSWC Carderock and their Maneuvering and Control Division, as well as other Navy laboratories and shipbuilding organizations involved in scaling and understanding three-dimensional shear flows near the air-water interface and at depth. Return