... for all of the drag on the body because they do not encompass the entire geometry. Therefore, in determining the point of self propulsion, the numerically predicted advance ratio will be higher than the experimentally determined value. Still, this was able to predict the point of self propulsion much...

...Fei Zheng; Andrey V. Kuznetsov; William L. Roberts; Daniel E. Paxson For many propulsion devices, the thrust may be augmented considerably by adding a passive ejector, and these devices are especially attractive for unsteady propulsion systems such as pulse detonation engines and pulsejets...

... was produced with a duct that produced zero mean flow acceleration. Ducted designs generating accelerating or decelerating flow increased drag. However, propulsive efficiency based exclusively on blade thrust and torque was significantly increased for accelerating flow through the duct and reduced...

...S. Gowing; T. Mori; S. Neely Air-augmented waterjets derive their propulsion from compressed gas mixed directly into the main flow. The gas bubbles expand as the mixture passes through the pressure gradient of the convergent nozzle, and energy is imparted to the water from the air in a complex...

..., and trim were predicted. Since the ship model is at the self-propulsion point, the difference between EFD R X , sinkage, and trim and CFD C T X , sinkage, and trim provides an assessment of the capability of the CFD waterjet model. Simulations and comparisons with EFD are also done...

...Kideok Ro This study was conducted in an attempt to improve the hydrodynamic performance of a Weis-Fogh type ship propulsion mechanism by installing a spring to the wing so that the opening angle of the wing can be changed automatically. With the prototype design, the average thrust coefficient...

.... , 2003 , “ Investigation of the Resistance, Propulsion, Stability and Control Characteristics of the NUWC/ARL UUV IMP from Captive Model Experiments ,” Naval Surface Warfare Center, Carderock Division, Report No. NSWCCD-50-TR-2003/010. Welch , J. R. , 2007 , “ Design & Implementation...

... earth-fixed reference frame, and ramping up the ship speed slowly such that the time derivatives become negligible and the local solution corresponds to a quasi steady-state. The procedure is used for the computation of resistance and propulsion curves, in both cases allowing for dynamic calculation...

...Kideok Ro; Baoshan Zhu; Hokeun Kang The velocity and pressure field of a ship’s Weis-Fogh-type propulsion mechanism are studied in this paper using an advanced vortex method. The wing (NACA0010 airfoil) and channel are approximated by source and vortex panels, and free vortices are introduced away...

... instability propulsion In devices such as pumps, turbines, and marine propellers, cavitation has many adverse effects including material erosion and performance degradation. In addition, it can give rise to instabilities that do not occur in single phase flow. For example, high-speed turbopumps often...

... of the Americas, and Wa¨rtsila¨ Propulsion. The authors wish to thank Mr. Kevin Mitchell and Dr. Brant Savander of Michigan Wheel for making available to them the geometry of a supercavitating propeller. α = angle of attack for 3-D hydrofoil C p = pressure coefficient, C p...

...Motomu Nakashima, Research Associate; Kyosuke Ono, Professor In our previous paper, we proposed a numerical method based on the discrete vortex method for a bending propulsion mechanism of fish or cetaceans in water, and we demonstrated its validity by comparing the results with an experiment using...

... velocimetry maps of vorticity-velocity vectors in the axial and cross-stream planes of the near-wake, as well as dye flow visualization. The mechanism of flapping foil propulsion and maneuvering is much richer than reported before. They can be classified as natural or forced. This work is of the latter type...

.../Reversing Exhaust Nozzles,” AIAA/ASME/SAE/ASEE 24th Joint Propulsion Conference , Boston, MA, Paper AIAA-88-3239. Nguyen, L. T., and Gilbert, W. P., 1990, “Impact of Emerging Technologies on Future Combat Aircraft Agility,” AIAA/SFTE/DGLR/SETP Fifth Biannual Flight Test Conference , Ontario, CA, Paper...

... in the JOURNAL OF FLUIDS ENGINEERING . Manuscript received by the Fluids Engineering Division February 19, 1998; revised manuscript received December 7, 1999. Associate Technical Editor: P. R. Bandyopadhyay. 19 February 1998 07 December 1999 biomechanics propulsion vortices wakes flow...