Patent ID: 6357374
Filing Date: 2002-03-19
Classification: B63B,Y02T

Abstract:
A method of ejecting a drag-reducing substance into a first fluid in a manner that avoids disruption and â€œblow-offâ€  of the first fluid and reduces the rate of diffusion of the drag-reducing substance in the first fluid to thereby increase the effectiveness of the drag-reducing substance in reducing drag of the first fluid in moving relative to a wall, said method comprising the following steps, performed in the order indicated:a) conditioning the drag-reducing substance by causing a second fluid, which includes the drag-reducing substance as a dispersed solid, liquid or gas microbubble and substance mixture, to flow through a nozzle that produces an axial velocity gradient within the second fluid containing the additive as a mixture or in solution, to thereby unwind, align and extend molecules of the drag-reducing substance; b) passing the second fluid by a vortex chamber, to establish a vortex within the vortex chamber, thereby reducing the vorticity of the second fluid; c) ejecting the second fluid through a first ejector, having an aperture in a wall, into the first fluid as said first fluid flows past said wall, said aperture formed to include a first Coanda surface as a portion thereof.