Abstract: The bearing structure such as a wing is fitted with toothed platelets (16) at its free edges to break tip vortex produced at these places by fluid pressure distribution. Vortex dissipation is accelerated, vortex remanence is considerably reduced. In the case of a deflector for a line of hydrophones (30) towed by a ship (31) to carry out seismic tests at sea, the noise disturbing the hydrophones (30) is reduced. In the case of marine applications, risks of cavitation are much reduced, particularly with regard to stabilizers or propellers. In the case of aeronautics applications, vortex remanence on take-off and on landing of planes is reduced.
Abstract: A method and device for operating special equipment provided in seismic cables, i.e., gun cables and streamers (2, 3) during seismic surveys at sea, whereby energy is supplied through wires (4), or wireless transmitting/receiving devices, to the equipment (B, C, D) in the cables, without this energy supply affecting the seismic surveys. In order to achieve this, low output energy (A) is supplied through wires (4, 17) to electrical units, such as a transformer (5) in a sealed chamber (9) used to charge batteries (6) in a separate sealed chamber (10) so that they can emit for brief periods sufficiently high outputs of energy in order to perform the necessary operation of the equipment such as motors (7) and fluid pumps ( 14 ) . Control devices ( 13 ) are provided where required for control of the operation.
Type:
Grant
Filed:
March 17, 1993
Date of Patent:
July 12, 1994
Assignee:
Geco AS
Inventors:
Odd O. Vatne, Hans Cappelen, Oyvind Sorbotten