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                                Motivation for Facility

       For the new algorithms and sensors that are currently being developed, a cost efficient testbed that mimics supercavitating conditions is required for experimentation. This provides the primary motivation for the University of Florida air-water shear-layer facility. This is because setting up a conventional supercavitating environment in lab conditions is a challenging and costly problem. Such a set-up would require a test section in which water flows at high speeds, even to maintain a supercavity under ventilating conditions. To circumvent the complexity and cost factor involved in such a project, an affordable solution is sought in the form of an air-water shear layer interface (see Figure 1-3).  A  supercavitating environment is mimicked by keeping the air speed at approximately 150 knots and maintaining the speed of water to be high enough to produce cavitation bubbles (approximately 1 m/s) [Sheplak et al. 1999]. This system is certainly a low cost option as conventional low speed air tunnels and water tunnels can be manufactured at a much lower cost than a custom water tunnel that has to propel water at high speeds.












    Figure 1-3 Schematic of interfacial conditions in the air-water shear layer facility.

       To assess the ability of an air-water shear layer facility to simulate the actual supercavitating conditions, a comparison of the air-water interface conditions in both