Abstract:
A frictionally reduced hull is provided for a marine vessel, the hull having a water line, a bow end and an aft end. The hull has a first opening below the water line and a second opening below the water line. The first opening is closer than the second opening to the bow end. A first conduit extends from the first opening to the second opening, whereby water flows into the conduit through the first opening and passes through the conduit from the first opening towards the second opening, exiting at the second opening. A second conduit extends into the first conduit between the first opening and the second opening, fluid being drawn into the first conduit via the second conduit and exiting at the second opening.
Abstract:
Formations on the surface of bodies for reducing the drag relative to a medium which the body is located in or close to. The formations comprise a plurality of cavities (1,20,40,60). The surface in which the cavities are formed is closed. The cavity has a disruption edge (5,25,44,66) adjacent to the cavity, with the disruption edge located upstream of the cavity, so as to set the flowing medium most proximal to the surface into turbulence upon passing the disruption edge. The cavity has a maximum depth from the surface of at least approximately 2 mm.
Abstract:
A human powered marine vehicle is provided having a rigid front section and a flexible rear section which may be flexed at at least two point therealong. The arms and/or legs of one or more persons in the vehicle are used to power actuators for each flex point, which actuators are operated so as to provide a predetermined relationship, and in particular at least a predetermined phase relationship, between flexure at the various points so that the flexible section moves with a wave or fish-like motion. The person(s) operating the vehicle is trained so as to maintain the predetermined relationship and various techniques are disclosed to assist the operator(s), or otherwise facilitate, the maintenance of the desired relationship.
Abstract:
The system includes radiation generation and transmission components which radiate tuned microwave electromagnetic energy outwardly from a vehicle through an antenna into a fluid medium through which the vehicle is moving. The microwave radiation is at the frequency of harmonic resonance electromagnetic excitation of the molecules of the medium which produces efficient heating of the fluid resulting in a reduction of the mass density thereof. This reduction decreases the drag forces acting on the vehicle resulting in a greatly enhanced aerodynamic and/or hydrodynamic efficiency and also decreases the intensity of the shock waves (which often lead to sonic booms). An aircraft's dramatically higher speed in the surrounding rarefied medium can make it appear to be travelling at "supersonic" speeds.
Abstract:
There is presented an underwater vehicle polymer ejection control valve ambly comprising a valve in communication with a polymer reservoir and in communication with ejection ports. The assembly further comprises a valve actuator including structure responsive to the vehicle in an ascending mode reaching a first predetermined depth in a water column to open the valve to place the polymer reservoir in communication with the ejection ports. The aforementioned structure is further responsive to the vehicle reaching a second and lesser predetermined depth to close the valve to interrupt communication between the polymer reservoir and the ejection ports.
Abstract:
A paint for application to the exterior surface of waterborne vehicles indes a high molecular weight water soluble polymer with drag reducing properties which time releases into the fluid boundary layer immediately adjacent the vehicle surface to reduce turbulence and promote laminar flow.
Abstract:
The present invention provides a method of reducing the fluid friction drag of ships and fluid transport channels and prevent contamination and corrosion of a structure having an immersed portion. The method of forming an air layer over an immersed surface of a structure having an immersed portion, comprising the steps of: covering the immersed surface of a structure (hull 1) having an immersed portion with a coating layer 3, which has depressions 6 and projections 7 at the surface thereof and which has at least vertices 7' of the projections 7 formed of a water-repellent material 8; and supplying air a to the surface 10 of the coating layer to form an air film 12 between the coating surface 10 and water 13.
Abstract:
An improved aerodynamic surface for the exterior of vehicles moving through a gas and vehicles employing such improved surfaces. The improved surface comprises a matrix of dimples or depressions formed into the portions of the surface of the vehicle. The improved surface is most beneficially located either at a leading edge, where the vehicle first cleaves the pool of air through which it is traveling, or on vehicle surfaces which tend to move the air pool to accommodate the presence of the vehicle itself or on vehicle surfaces to which the designer wishes to provide a lift function. Wings, ailerons and rudder surfaces are examples of surfaces to which a lift function is most applicable. The vehicle may be of the nature of an automobile, a boat or an airplane. The invention is also applicable to the internal surface of pipes for conveying fluid.
Abstract:
The boundary layer of a fluid travelling in a mean-flow direction relative to a surface of a wall of a body is controlled by generating in a near-wall region of the flow a magnetic field B having flux lines parallel to the surface of the wall and an electric current density J traversing the magnetic flux lines in the fluid. An electrolyte or other conductivity-enhancing material is introduced into the flow to provide an electrical conductivity gradient in the near-wall region. The magnetic field B and the electric current density J create in the fluid a force J.times.B having a component normal to the surface of the wall that because of the increased conductivity gradient near the surface can stabilize or destabilize flow in the boundary layer. Numerous aspects of the fluid flow and its interaction with the body can thus be controlled. As examples, shear stress in the fluid at the wall can be decreased, with a corresponding reduction in viscous drag, the characteristics of the acoustic and pressure fields in the fluid surrounding the body can be controlled to reduce noise and fatigue, and boundary layer separation can be inhibited or induced.
Abstract:
A plurality of plate members for covering the outside of a ship's hull includes a base plate for shaping the plate members. The plate members are each coated with an inner and outer rubber resilient surface. Fasteners are used to attach the plate members to the ship's hull.