Results 251 to 260 of about 3,835 (288)

Liquid resistance in underwater laser propulsion

Applied Optics
To investigate liquid resistance in underwater laser propulsion, we conducted underwater propulsion experiments with cylindrical titanium targets of identical mass but varying propulsion areas through high-speed photography. An analytical formula was derived to elucidate the relationship among the kinetic energy of the target, the energy of the bubble ...
Hao, Qiang, Yi, Gao, Jun, Chen, Yang, Li, Yuya, Cui, Yan, Zhao, Qinggong, Hou   +6 more
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Myometry-driven compliant-body design for underwater propulsion

2010 IEEE International Conference on Robotics and Automation, 2010
Within the broader scope of underwater biomimetics, in this paper we address the relevance of factors such as shape and elasticity distribution in the ability of a compliant device to imitate the kinematic behaviour of a fish. We assess the viability of myometry as a tool to determine candidate mechanical parameters without relying solely on analytical
Otar Akanyeti, Andres Ernits, Maria-Camilla Fiazza, Gert Toming, Guntis Kulikovskis, Madis Listak, Rasmus Raag, Taavi Salumae, Paolo Fiorini, Maarja Kruusmaa   +9 more
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THE HYDRODYNAMICS OF UNDERWATER JET PROPULSION

1953
Abstract : Force measurements were obtained with a new sensitive balance for a range of nose shapes and cavitation parameters (K) under conditions of open- cavity flow. Drag-coefficient (CD) data were obtained for a 12- to 25-ft/sec range on model sizes ranging from 0.500 to 1.414 in. in diameter for the sharper cone.
openaire   +2 more sources

The mechanism of flapping propulsion of an underwater glider

Journal of Hydrodynamics, 2016
Abstract To develop a bionic maneuverable propulsion system to be applied in a small underwater vehicle, a new conceptual design of the bionic propulsion is applied to the traditional underwater glider. The numerical simulation focuses on the autonomous underwater glider (AUG)'s flapping propulsion at by solving the incompressible viscous Navier ...
Yong-cheng Li, Ding-yi Pan, Zheng Ma
openaire   +1 more source

Multiphase Computations for Underwater Propulsive Flows

16th AIAA Computational Fluid Dynamics Conference, 2003
An algorithm for modeling compressible phenomena in multi-phase, reacting flows is developed. Time-marching preconditioned methodology is used as the algorithmic framework because of its inherent capability of handling multiple flow regimes, such as the incompressible bulk liquid flow, low Mach number compressible vapor flow and transonic/supersonic ...
Jules Lindau, Sankaran Venkateswaran, Robert Kunz, Charles Merkle   +3 more
openaire   +1 more source

Magnetohydrodynamic Underwater Vehicular Propulsion Systems

Proceedings of the 25th Intersociety Energy Conversion Engineering Conference, 2005
The development of magnetohydrodynamic propulsion systems for underwater vehicles is a high risk endeavor that offers the possibility of anumber of significant advantages over conventional propeller propulsion systems. These advantages may include the potential for greater stealth characteristics, increased maneuverability, enhanced survivability ...
D.W. Swallom, I. Sadovnik, J.S. Gibbs, H. Gurol, null Long Nguyen   +4 more
openaire   +1 more source

Propulsive efficiency of underwater vehicles using unsteady propulsors

2013 American Control Conference, 2013
This study examines the propulsive efficiency of underwater vehicles which are driven by unsteady propulsors. The analysis is focused on vehicles utilizing a novel thruster which expels finite propulsive jets periodically. This analysis also applies to swimming squid and jellyfish (from which the thruster was inspired), and can be extended to any ...
Michael Krieg, Kamran Mohseni
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Stored chemical energy propulsion system for underwater applications

17th Joint Propulsion Conference, 1981
An underwater propulsion system that couples a lithium fueled boiler with a standard Rankine cycle has been developed and demonstrated in an ocean environment. Although the demonstration vehicle was a small diameter axisymmetric body, other configurations have been subjected to study and experimentation.
T. G. Hughes, R. B. Smith, D. H. Kiely
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Propulsive efficiency of a biomorphic pulsed-jet underwater vehicle

Bioinspiration & Biomimetics, 2010
The effect of the velocity program and duty cycle (St(L)) on the propulsive efficiency of pulsed-jet propulsion was studied experimentally on a self-propelled, pulsed-jet underwater vehicle, dubbed Robosquid due to the similarity of essential elements of its propulsion system with squid jet propulsion.
Ali A, Moslemi, Paul S, Krueger
openaire   +2 more sources

DEVELOPMENT OF A LITHIUM RECHARGEABLE BATTERY FOR UNDERWATER VEHICLE PROPULSION

Naval Engineers Journal, 1991
ABSTRACTThe Navy is researching lithium rechargeable batteries as a possible replacement for silver oxide/zinc cells in powering the next generation of naval underwater vehicles. This paper summarizes progress made with the most promising lithium system — lithium/cobalt oxide, which has 2.5 times the theoretical energy density of silver oxide/zinc ...
PATRICIA H. SMITH, DAVID L. CHUA, STANLEY D. JAMES   +2 more
openaire   +1 more source