Accession Number : ADA604777


Title :   Pitching Flexible Propulsors: Experimental Assessment of Performance Characteristics


Descriptive Note : Trident Scholar Project rept. no. 425


Corporate Author : NAVAL ACADEMY ANNAPOLIS MD


Personal Author(s) : Egan, Brendan C


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a604777.pdf


Report Date : 09 May 2014


Pagination or Media Count : 60


Abstract : Many applications for Autonomous Underwater Vehicles (AUV) require higher maneuverability than is available with traditional propulsion. An understanding of flexible propulsor performance characteristics is required for application in marine systems. This project investigates relationships between a flexible propulsors' instantaneous shape, performance, and interaction with the surrounding fluid. The analysis is conducted through reduction of the measured force and torque data and multiple wake flow analysis techniques, including particle image velocimetry and dye injection. The experiments take place in USNA's large water channel, using full span flexible propulsor models. The propulsor pitches about a fixed axis at its quarter chord, with a six-axis load cell measuring the forces and torques on the shaft. The non-dimensional parameters, the Reynolds Number, Strouhal Number, and Stiffness Constant, act as a reference for the efficiency of the propulsor and the Coefficients of Thrust and Lift. The ensemble data will facilitate the engineering of fish-like propulsion systems for future application of this technology.


Descriptors :   *BIOENGINEERING , *MARINE PROPULSION , EXPERIMENTAL DESIGN , FISHES , FLEXIBLE STRUCTURES , HYDRODYNAMICS , HYDROELASTICITY , MANEUVERABILITY , SELF OPERATION , SWIMMING , TORQUE , UNDERWATER VEHICLES


Subject Categories : Marine Engineering
      Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE