Polymer drag reduction systems on vehicle surfaces

Patent metadata

Field	Value
Publication number	US-10023267-B2
Application number	US-201615255831-A
Country	US
Kind code	B2
Filing date	Sep 2, 2016
Priority date	Sep 4, 2015
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

Systems and methods of reducing drag on outer surfaces of vehicles that are in contact with water using a polymer solution that reduces the drag on the outer surfaces of the vehicles as the vehicles travel through water. A polymer solution is passively ejected into the boundary layer of the water flowing past the outer surface of the vehicle. The polymer solution is mixed and introduced into the boundary layer passively with minimal or no usage of electrical energy. The passive mixing and ejection of the polymer solution minimizes energy consumption, thereby maximizing electrical energy consumption efficiency during operation of the vehicle.

First claim

The invention claimed is:

1. A reduced drag vehicle, comprising:
a structure having a forward end, an interior, and an outer surface;
a plurality of water inlets in the forward end through which water can flow into the interior of the structure;
a mixing chamber in the interior of the structure in fluid communication with the plurality of water inlets and receiving water that flows into the structure through the plurality of water inlets;
a liquid polymer within a storage chamber disposed in the interior of the structure;
at least one fluid passage extending from the storage chamber and fluidly connecting to the mixing chamber to allow the liquid polymer from the storage chamber to mix with the water in the mixing chamber to form a polymer solution;
a metering valve in the at least one fluid passage that controls the flow of the liquid polymer from the storage chamber into the mixing chamber;
a plurality of polymer solution outlets in the outer surface in fluid communication with the mixing chamber through which the polymer solution is ejected from the structure into a boundary layer to reduce drag on the outer surface as the structure moves in a forward direction through water with the water flowing past the forward end and then over the polymer solution outlets in the outer surface;
the plurality of water inlets are positioned forwardly of the plurality of polymer solution outlets;
the plurality of polymer solution outlets are positioned rearwardly of at least a portion of the mixing chamber; and
the pressure at the water inlets is higher than the pressure at the polymer solution outlets so that the polymer solution is passively ejected from at least one of the polymer solution outlets.

2. A reduced drag vehicle, comprising:
a structure having a forward end, an interior, and an outer surface;
a plurality of water inlets in the forward end through which water can flow into the interior of the structure;
a mixing chamber in the interior of the structure in fluid communication with the plurality of water inlets and receiving water that flows into the structure through the plurality of water inlets;
a polymer within the interior of the structure in communication with the mixing chamber, the polymer mixes with the water in the mixing chamber to form a polymer solution;
a plurality of polymer solution outlets in the outer surface in fluid communication with the mixing chamber through which the polymer solution is ejected from the structure into a boundary layer to reduce drag on the outer surface as the structure moves in a forward direction through water with the water flowing past the forward end and then over the polymer solution outlets in the outer surface;
the plurality of water inlets are positioned forwardly of the plurality of polymer solution outlets;
the plurality of polymer solution outlets are positioned rearwardly of at least a portion of the mixing chamber;
the pressure at the water inlets is higher than the pressure at the polymer solution outlets so that the polymer solution is passively ejected from at least one of the polymer solution outlets;
the polymer is a liquid polymer that is contained in a storage chamber that is fluidly connected to the mixing chamber; and
wherein the storage chamber is a compressible bladder, the compressible bladder is exposed to ambient pressure of water that the reduced drag vehicle is operating in, and further comprising a force applying mechanism acting on the compressible bladder.

3. The reduced drag vehicle of claim 1 , wherein the reduced drag vehicle is devoid of an electrically driven pump so that water that flows into the plurality of water inlets, the liquid polymer and the polymer solution are not distributed by a pump.

4. A reduced drag vehicle, comprising:
a structure having an interior, a forward end, and at least one outer surface that is subject to drag as a result of the structure moving in a forward direction through water with the water flowing past the forward end and then over the at least one outer surface;
a compressible bladder contained in the interior of the structure and exposed to ambient pressure, the compressible bladder containing a liquid polymer;
a mixing chamber in the interior of the structure in fluid communication with the compressible bladder to receive liquid polymer therefrom;
a metering valve that controls the flow of liquid polymer from the compressible bladder into the mixing chamber;
at least one water inlet on the structure through which water can flow into the interior of the structure, the at least one water inlet is fluidly connected to the mixing chamber;
wherein liquid polymer from the compressible bladder and water from the at least one water inlet mix in the mixing chamber to form a polymer solution;
a polymer solution discharge line fluidly connected to the mixing chamber;
at least one polymer solution outlet formed in the at least one outer surface that is subject to drag and fluidly connected to the polymer solution discharge line to discharge polymer solution from the at least one polymer solution outlet to reduce drag on the at least one outer surface; and
the pressure at the at least one water inlet is higher than the pressure at the at least one polymer solution outlet so that the polymer solution is passively ejected from the at least one polymer solution outlet without use of an electrically driven pump.

5. The reduced drag vehicle of claim 4 , wherein the structure is a hull, and the at least one outer surface is a surface of the hull.

6. The reduced drag vehicle of claim 4 , wherein the structure is a fixed or actuatable fin, and the at least one outer surface is an outer surface of the fin.

7. The reduced drag vehicle of claim 4 , wherein the structure is a duct of a propulsion mechanism, and the at least one outer surface is an outer surface of the duct.

8. The reduced drag vehicle of claim 4 , further comprising a force applying mechanism acting on the compressible bladder.

9. A reduced drag vehicle, comprising:
a structure having an interior, a forward end, and at least one outer surface that is subject to drag as a result of the structure moving through water with the water flowing past the forward end and then over the at least one outer surface;
at least one water inlet on the structure through which water can flow into the interior of the structure;
a mixing chamber in the interior of the structure and fluidly connected to the at least one water inlet and receiving water that flows into the structure through the at least one water inlet;
a water-soluble solid polymer disposed in the mixing chamber, wherein water entering the mixing chamber dissolves at least a portion of the water-soluble solid polymer to form a polymer solution in the mixing chamber;
at least one polymer solution outlet formed in the at least one outer surface that is subject to drag and fluidly connected to the mixing chamber to discharge polymer solution from the at least one polymer solution outlet to reduce drag on the at least one outer surface;
the at least one water inlet is positioned forwardly of the at least one polymer solution outlet; and
the at least one polymer solution outlet is positioned radially outward of the water-soluble solid polymer and the mixing chamber.

10. The reduced drag vehicle of claim 9 , wherein the structure is a hull, and the at least one outer surface is a surface of the hull.

11. The reduced drag vehicle of claim 9 , wherein the structure is a fixed or actuatable fin, and the at least one outer surface is an outer surface of the fin.

12. A reduced drag vehicle, comprising:
a structure having an interior, a forward end,

Assignees

• Lockheed Corp

Inventors

• Brandes John C
• Bullock Steven Edward
• Cuschieri Joseph M
• Forst Vincent J
• Said Brian Robert
• Solenski Joseph M

Classifications

• B63G8/04

  Superstructure · CPC title

• B63B2001/345

  by ejecting friction reducing solids or liquids, e.g. polymers · CPC title

• B63G2008/004

  autonomously operating · CPC title

• B63B1/34 Primary

  by reducing surface friction · CPC title

• B63G8/001

  Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations (self-propelled or direction controlled diving chambers with mechanical link to a base B63C11/42) · CPC title