The new OTTER facility stands for Optical Towing Tank for Energetics Research. With a cross-section of 1m x 1m and an overall length of 15m, the high-speed traverse system is able to hit Reynolds numbers on the order of a million. The ceiling is sealed to prevent free-surface effects (sloshing) but free-surface testing can be accommodated by lowering the waterline slightly. Optical measurement techniques such as time-resolved PIV and 4D-PTV are employed for direct flow measurements. An ATI Nano submersible six-component balance is used for direct force and moment measurements. For more details on this new world-class facility please see the following:
OTTER II maintains the same cross-section as OTTER I at 1m x 1m but with a shortened overall length of 8m. The focus of this facility is on two-phase problems such as particle-laden flows, where a custom shear generator is towed through to generate turbulence in the medium. Planar and volumetric imaging techniques such as PIV and PTV are employed here.