Skin Friction Measurement Technology for Underwater Applications Navy SBIR FY2010.1 Sol No.: Navy SBIR FY2010.1 Topic No.: N101-098 Topic Title: Skin Friction Measurement Technology for Underwater Applications Proposal No.: N101-098-1171 Firm: Innovative Scientific Solutions, Inc. 2766 Indian Ripple Rd Dayton, Ohio 45440-3638 Contact: Jim Crafton Phone: (937) 429-4980 Web Site: www.innssi.com Abstract: The measurement of skin friction on hydrodynamic surfaces at high Reynolds numbers is essential for the design of advanced Naval technology. Knowledge of the mean skin friction and flow separation is essential for the validation of computational models and design of advanced maneuvering systems. Unfortunately, the accurate measurement of wall skin friction on complex surfaces under high Reynolds number continues to be problematic. In this proposal we introduce an optical sensor for measurements of mean skin friction on large models that operates in water. This sensor is based on the diffusion of a fluorescent dye from a polymer film into the water, a mass transfer sensor. Mass transfer is determined by monitoring the rate of dye diffusion from the film and applying a transient model to the process. This technique has been demonstrated qualitatively by detecting boundary layer transition on an airfoil model in the 12-inch water tunnel at Penn State University. In the Phase I effort, a series of sensors will be manufactured and tested on a flat plate in the Penn State University water tunnel at Reynolds numbers of up to 9-million. Skin friction results from the new sensor will be compared to established techniques. Benefits: Distributed measurements of skin friction are of significant interest in a variety of fields including aeronautical and bio-medical engineering. ISSI is currently pursuing commercial applications in these fields by demonstrating skin friction and pressure measurements on aerodynamic models, micro-channels, artificial heart models, and contact force sensors. In the aeronautical community, the skin friction measurements offered by this technique are essential for the validation of CFD codes and the design of low Reynolds number airfoils for micro air vehicles. For the bio-medical field, measurements of skin friction are essential to the design of artificial implants to minimize the occurrence of clotting. Other bio-medical applications include the design of assist pumps. In conjunction with these proof of concept tests, ISSI has recently developed a commercial Pressure Sensitive Paint system. The components of the skin friction technology have been developed to be compatible with this commercially deployed system and therefore, extension of these systems to include skin friction measurements is offered as a system upgrade. Over the past 12 months, eight complete systems and several components have been sold with total revenue of over $700,000. Return