Mixed regime passive valve

Patent metadata

Field	Value
Publication number	US-11519508-B1
Application number	US-202117313092-A
Country	US
Kind code	B1
Filing date	May 6, 2021
Priority date	May 6, 2021
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

A system for gas extraction is provided with a flap valve coupled to a bore with a pivot axis offset from an axis of the bore. The valve includes a higher mass on a shorter side of the pivot axis. A valve surface on the shorter side is inclined above a horizontal plane when the valve closes. The valve opens during liquid and gas flow to extract gas from the flow. As liquid flows over the valve, the valve is forced to close. The center of gravity of the valve relative to the offset pivot point ensures that the valve remains closed during liquid flow. As gas flows over the valve, closing forces are reduced and under internal vacuum, the mass distribution about the offset pivot axis allows the flap of the valve to tilt; opening the valve and allowing gas to enter the bore.

First claim

What is claimed is:

1. A valve system for gas extraction, said valve system comprising: a vertically arranged bore having a central axis; and
a pivotable flap valve coupled to said bore with said flap valve having a pivot axis axially offset from the central axis of said bore, said flap valve having a higher mass on a first, shorter side of the pivot axis with a top surface of said flap valve on the shorter side of the pivot axis inclined above a horizontal plane when said flap valve is closed;
wherein said flap valve is closed covering said bore during flow of a liquid over said valve system, and wherein said flap valve is open partly exposing said bore during flow of only gas over the valve system thereby allowing gas to enter the bore.

2. The system of claim 1 , wherein the horizontal plane is along a rim of said bore with said system further comprising a peripheral portion of said flap valve adjoining the top surface of said flap valve protruding outward from the horizontal plane when said flap valve is closed.

3. The system of claim 2 , wherein the rim of said bore is radially symmetric and wherein an inner surface of said bore includes a first arcuate section and a second arcuate section alternating with a first flat section and a second flat section.

4. The system of claim 3 , wherein the coupling of said flap valve at the pivot axis includes attaching said flap valve to each of a first pivot point on the first flat section and a second pivot point on the second flat section, the pivot axis connecting the first pivot point and the second pivot point.

5. The system of claim 4 , further comprising a restraining lip along the second arcuate section of the inner surface of said bore extending from the first flat section to the second flat section.

6. The system of claim 5 , wherein said flap valve is subdivided into a second, longer side between the pivot axis and the second arcuate section, and the first, shorter side between the pivot axis and the second arcuate section, the central axis passing through the second, longer side.

7. The system of claim 6 , wherein the first, shorter side includes a hemispherical lower surface, the hemispherical lower surface leading to a cylindrical section.

8. The system of claim 7 , wherein when said flap valve is closed, an edge of the second side of said flap valve rests on said restraining lip forming a first angle between the horizontal plane of the rim and an upper surface of the second side of said flap valve.

9. The system of claim 8 , wherein when said flap valve is open, the second side of said flap valve tilts within said bore forming a right angle between the horizontal plane of the rim and the upper surface of the first side of said flap valve protrudes out of the horizontal plane.

10. The system of claim 1 , wherein said flap valve dynamically opens by rotating about the pivot axis in a first direction in an absence of hydrodynamic forces and a presence of an internal vacuum, and wherein said flap valve dynamically closes by rotating in a second direction about the pivot axis due to the hydrodynamic forces exerted by the liquid flowing over said valve system regardless of the presence of the internal vacuum, the second direction being opposite to the first direction.

11. A method for operating a passively actuated valve coupled at an opening of a passage, said method comprising the steps of:
closing the valve by exerting hydrodynamic forces generated by a flow of a liquid over a flap of the valve;
opening the valve by suspending the flow of the liquid over the flap and applying vacuum within the passage; and
routing a gas flowing over the valve into the passage via the opened valve, the flap coupled to the opening along a pivot axis offset relative to a central axis of the opening.

12. The method of claim 11 , wherein the flap includes a first, heavier segment on a first side of the pivot axis and a second, lighter segment on a second side of the pivot axis.

13. The method of claim 12 , wherein the flap rotates counter-clockwise in a range of 30-60° about the pivot axis for opening the valve and wherein the flap rotates clockwise about the pivot axis for closing the valve.

14. The method of claim 13 , wherein upon closing of the valve, a top surface of the first, heavier segment is tilted upwards out of a horizontal plane of a rim of the passage and a top surface of the second, lighter segment is angled inward within the passage forming a first angle between the horizontal plane of the rim and the top surface of the second, lighter segment.

15. The method of claim 14 , wherein upon opening of the valve, is angled inward within the passage forming a second angle between the horizontal plane of the rim and the top surface of the second, lighter segment, and the first, heavier segment is protruded outward from the horizontal plane, the second angle larger than the first angle.

16. A method for a flap valve regulating flow of fluid into a bore, said method comprising the steps of:
during a first condition, opening the valve passively by rotating the flap valve about an off-centered pivot axis in a first direction in a presence of internal vacuum to allow flow of gases into the bore; and
during a second condition, closing the valve passively by rotating the flap valve about the off-centered pivot axis in a second, opposite, direction in the presence or absence of internal vacuum to block liquids from entering the bore, the flap valve includes unequal mass distribution about the off-centered pivot axis.

17. The method of claim 16 , wherein the first condition includes a flow of only gases over a surface contacting the flap valve in the presence of the internal vacuum, and wherein the second condition includes a flow of liquids over the surface applying dynamic force on the valve.

18. The method of claim 17 , wherein the off-centered pivot axis is shifted towards one side of a central axis of the bore, the flap valve rotatable in a range of 30-60° about the pivot axis.

19. The method of claim 18 , wherein the unequal mass distribution includes a heavier, first segment of the flap valve on a first side of the pivot axis including a hemispherical lower surface, and a lighter, second segment of the flap valve on a second side of the pivot axis including a cutout on a lower surface.

Assignees

• Us Navy

Inventors

• Dooley Richard E
• Chapman John H

Classifications

• F16K27/0227

  with the valve members swinging around an axis located at the edge of or outside the valve member · CPC title

• B01D19/0063

  Regulation, control including valves and floats (for construction and details of valves F16K) · CPC title

• F16K1/2014 Primary

  Shaping of the valve member · CPC title

• F16K15/034

  weight-loaded · CPC title

• F16K1/222

  Shaping of the valve member · CPC title