Experimental analysis of the three-dimensional vortex wakes generated by bio-inspired body-cauldal fin flow field interactions
Abstract
Experimental analysis of the three-dimensional vortex wakes generated by bio-inspired body-cauldal fin flow field interactionsBio-inspired hydrodynamic propulsion mechanisms have great potential for a range of man-made naval vehicles. The swimming of fish and aq"uatic mammals has been observed to be exceedingly efficient (migrating whales), powerful (hunting sharks), or maneuverable (articula""ting reef fish). In order to employ these locomotive characteristics for engineered vehicles, it must first be established what th""e connections are among the design and actuation of the body, the flow field generatedby that body motion, and the actual forces,"" moments, and efficiencies of the resulting propulsiveperformance. In the proposed work, previous results on isolated caudal- fin-l""ike models with be augmented with upstream fish/mammal-like bodies in order to explore the flow- fields generated by each, along wi"th their dynamic interactions. It will be explored whether these interactions are inherently constructive or destructive for swimmin"g performance, or whether that relationshipcan change with a variation in non-dimensional parameters associated with the kinematics"" of thebody motion, or the geometry of the body and tail design. To accomplish this, the team will usescanning stereoscopic PIV me"asurements in a water tunnel facility to measure and recreate phase-averaged three-dimensional flow fields around the body and ca"udal fin models. This velocity fielddata will be post-processed using the finite-time Lyapunov exponent (FTLE), which has previo"uslydemonstrated the ability to reveal the underlying structure of vortex-dominated three-dimensional flow fields. These results w"ill be combined with time-resolved force measurements to establish the connection between body motion profile, flow field structure"", and performance. From there, a strategy for design and actuation of efficient platforms that take advantage of (or mitigate negati"ve effects of) flow field interactions can be proposed.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 01, 2017
- Source ID
- N000141712759
Entities
People
- Melissa A. Green
Organizations
- Office of Naval Research
- Syracuse University
- United States Navy