A supersonic coaxial jet facility has been designed to provide experimental data suitable for the validation of CFD codes used to analyze high-speed propulsion flows. The center jet is of a light gas and the coflow jet is of air, and the mixing layer between them is compressible. Various methods have been employed in characterizing the jet flow field, including schlieren visualization, pitot, t...

The Draper Laboratory Vorticity Control Unmanned Undersea Vehicle (VCUUV) is the first mission-scale, autonomous underwater vehicle that uses vorticity control propulsion and maneuvering. Built as a research platform with which to study the energetics and maneuvering performance of fish-swimming propulsion, the VCUUV is a self-contained free swimming research vehicle which follows the morpholog...

Compact zero-mass pulsatile jet actuators are proposed for low speed maneuvering, ducking, and station keeping of small underwater vehicles. To this end, optimization of synthetic jets for maximal thrust generation is investigated. Flow field of such jets are initially dominated by vortex ring formation. Pinched-off vortices characterize the extremum impulse accumulated by the leading vortex ri...

Although various hydrodynamic models have been used in past analyses of squid jet propulsion, no previous investigations have definitively determined the fluid structure of the jets of steadily swimming squid. In addition, few accurate measurements of jet velocity and other jet parameters in squid have been reported. We used digital particle imaging velocimetry (DPIV) to visualize the jet flow ...

abstract in this study, the effect of suspended load transport on the characteristics of submerged hydraulic jump (shj) in a rectangular channel was investigated experimentally. sediment concentration and jet froude numbers in the range of 0.424%-16.15% and 1.93-4.96, respectively, were considered. tow grain size 0.15 and 0.03 mm were used in the experiments. characteristics of submerged hydrau...

mechanical, hydraulic, and chemical washing methods are the most common methods for sewer line cleaning. each of these methods includes several sub methods. rodding and bucket machine are the two most important of mechanical cleaning methods, whereas high-speed and flushing are the most important hydraulic cleaning methods. acids, alkalis, surfactants, and enzymes are widely used materials in s...

When a pump is propelled by propeller, the nozzle flooding of jet wake area will produce turbulent quasi-sequence structure and have certain impact on outflow field thrust characteristics water propulsion pump. In this paper, method that combined numerical simulation with vortex dynamics adopted, which analyzes dynamic influence A large eddy turbulence model dimensionless velocity coefficient w...

SPIRIT. A. F. C. Haldemann, L. Crumpler, J. A. Grant, M. P. Golombek, B. A. Cohen and J. W. Rice Jr., Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 ([email protected]); New Mexico Museum of Natural History and Science, Albuquerque, NM 87104; Center for Earth and Planetary Studies, National Air and Space Museum, Smithsonian Institution, Washingto...