Loading patent…
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorsDavid B. Coakley, Stephen M. Shepherd, David A. Newborn
Estimating the term…
In the absence of inventive practice, the hydrodynamic flows on both sides of a vertically oriented bluff body (e.g., cylinder) traveling through water tend to hug the bluff body proximate its curved back surface and to converge behind the bluff body, resulting in lateral sway of the bluff body. Exemplary inventive practice provides for attachment of a pair of waterjet-streaming devices at opposite axial ends of a bluff body such as a cylinder. The waterjet streams discharged by the two inventive devices, which adjoin the vertical bluff body, deflect the hydrodynamic flows on both curved side surfaces of the bluff body. The inventive apparatus thereby encourages a continued approximate parallelity of the hydrodynamic flows behind the bluff body, resulting in significantly greater stability of the bluff body. Some exemplary embodiments of the present invention provide for attachment of a single waterjet-streaming device at one axial end of the bluff body.
An apparatus for effecting self-stabilizing movement in a fluidic environment, the apparatus comprising:
A method for stabilizing an approximately cylindrical vehicular structure characterized by a geometric longitudinal axis, an axial surface, and two axial ends, said axial surface having two lateral surface areas on opposite sides of said geometric longitudinal axis, the method comprising:
Hydrodynamic apparatus for use in association with an axisymmetric bluff body characterized by an approximately vertical geometric axis, two axial ends, and an exterior axial surface, the hydrodynamic apparatus comprising a device characterized by a substantially linear front edge, two curvilinear side edges, an approximately horizontal longitudinal geometric axis approximately perpendicular to said substantially linear front edge, and substantial axial symmetry with respect to said approximately horizontal longitudinal geometric axis, said device including a conduit for intake of hydrodynamic flow at said substantially linear front edge and for output of jet streaming at each said curvilinear side edge, said device being attachable to said axisymmetric bluff body at a said axial end so that said approximately horizontal longitudinal geometric axis and said approximately vertical geometric axis approximately perpendicularly intersect, wherein interaction of said jet streaming with at least some said hydrodynamic flow that is tangential to said exterior axial surface of a moving said axisymmetric body results in separation of at least some said tangential hydrodynamic flow from said exterior axial surface.
Dependencies are inferred from the claim text.