Experiments with impulsive motion of a foil to generate large lift and thrust forces

As underwater vehicles become increasingly versatile and capable, bio-inspired propulsion systems are becoming a viable possibility for future vehicles. In particular, flapping foil actuators are promising in their abilities for propulsion and maneuvering. Current underwater vehicles rely on propellers, which form a jet wake to produce propulsion forces, and, as such, experience an inherent delay between the movement of the propeller and the vehicle feeling a propulsive force. To mitigate this shortcoming, flapping foils were moved in swift, one-time strokes to produce large, transient forces in still water to produce propulsive and/or maneuvering forces almost instantaneously. Previous work produced trajectories, characterized by heave and pitch motions, for which the lift and thrust profiles were confirmed. These strokes take advantage of added mass/inertial effects to produce propulsive forces useful for maintaining position or orientation or for precise maneuverability. Various novel combinations of heave and pitch motions were tested and dye visualization was performed with a custom wing to elucidate the wake and vortical structures produced by these strokes.

Name thesis:degree_name

Master

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2019

Author dc:creator

• Kotidis, Miranda.

Advisor dc:contributor.advisor

• Michael Triantafyllou.

• Mechanical Engineering.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/123749

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/123749