IMPROVEMENTS IN OR RELATING TO FLUID JETS ASSOCIATED WITH SUBSEA EXCAVATION

摘要

The present invention relates to improvements in or relating to fluid jets and their effects and apparatus that can be developed to take advantage of specific forms of jets and methods of performing functions using such jets. We describean apparatus comprising a body having a fluid flow path defined between a fluid inlet and a fluid outlet and thrust means (4) mounted within the fluid flow path to direct, in use, a flow of fluid, along the fluid flow path. At least a portion of the fluid flow path comprises a duct (1) and the thrust means comprises a propeller (4) mounted within the duct. The apparatus further comprises a plate (25) spaced from the fluid inlet defining a space therebetween; wherein a plurality of elongate pivotable vanes (22) are positioned in a circular orientation in the space, about the axis of the flow path and with their pivoting axes (26) aligned with the axis of the flow path. The thrust means (4) is adapted to rotate in a direction opposite to the direction of flow of fluid through the vanes (22) into the space.