GB2267976A

GB2267976A - Vortex valve flow control

Info

Publication number: GB2267976A
Application number: GB9212368A
Authority: GB
Inventors: Robert Philip Maudslay Smisson
Original assignee: Hydro International Ltd
Current assignee: Hydro International Ltd
Priority date: 1992-06-11
Filing date: 1992-06-11
Publication date: 1993-12-22
Also published as: GB9212368D0

Abstract

A liquid barrier 3 having an opening (5a) through which liquid may flow across the barrier and an associated vortex valve flow control (6) which is arranged in communication with the opening (5a) to control passage of liquid through the barrier (3), characterised in that the vortex chamber (10) of the vortex valve flow control (6) does not extend in a direction upstream of the liquid barrier (3). Such valves are often used in sewers and gullies to cope with storm conditions, and can be damaged by cleaning equipment if they protrude, as has been the case previously, into the gullies. <IMAGE>

Description

VORTEX VALVE FLOW CONTROL This invention relates to vortex valve flow controls.

Vortex valves are devices for controlling fluid flow by a hydraulic effect without requiring moving parts. US Patent No. 4206783 discloses a vortex valve having a conical vortex chamber with a tangential inlet and an outlet at the narrow end of the chamber. At low flow rates, water entering through the inlet passes through the vortex chamber to the outlet with substantially no pressure drop and the valve can be considered to be open. However, at high flow rate water enters through the inlet with enough energy to create a vortex in the vortex chamber which results in a considerable pressure drop between the inlet and the outlet and may greatly restrict flow through the outlet, or even substantially cut it off altogether.

Thus, the valve serves to limit the rate of flow through it automatically. Vortex valves of this type can be used, for example, to control the flow of storm water in sewers, to ensure that equipment downstream of the valve is not overloaded during periods of heavy rainfall.

GB-A-2210995 describes a vortex valve flow control in which the upstream end wall of the housing is provided with an opening normally closed by a closure, the opening being operable, by means remote from the vortex-valve, between the closed position and an open position, in which open position liquid may enter the vortex chamber by-passing the inlet.

A problem associated with vortex valves which are situated at the outlet opening of road gullies is that they are susceptible to damage by cleaning equipment which is periodically employed to remove detritus from the bottom of road gullies. Typically, such equipment comprises a flexible hose to which is attached a heavy shoe which, in use, is dropped into the road gully and sinks to the bottom thereof; liquid and associated detritus is then withdrawn, under reduced pressure, from the base of the road gully. Unfortunately, it is difficult to guide the cleaning apparatus accurately to the position at which it is required in the bottom of the road gulley and, as a result, vortex valve flow controls situated at the outlet opening of the road gully are prone to being damaged, and even of being knocked away from their position at the outlet of the gulley.

With a view to alleviating this problem, it is now proposed to provide, in accordance with the present invention, a liquid barrier having an opening through which liquid may flow across the barrier and a vortex valve flow control which is arranged in communication with the opening to control passage of liquid through the barrier, characterised in that the vortex chamber of the vortex valve flow control does not extend in a direction upstream of the liquid barrier.

The vortex valve flow control employed in the present invention comprises a housing defining the vortex chamber, there being an inlet through which liquid may enter the vortex chamber in a manner to promote swirl within the vortex chamber and an outlet at one axial end of the vortex chamber.

Preferably, the upstream end of the housing is provided with an opening normally closed by a closure, said opening being operable between the closed position and an open position (in which open position liquid may enter the vortex chamber by-passing the inlet) preferably by means which are remote from the vortexvalve.

In a first embodiment of the present invention, the vortex chamber may be formed or located wholly within the liquid barrier itself. Thus, the vortex chamber may be formed within the liquid barrier by, for instance, a moulding or casting technique in which a recess in the shape of a desired vortex chamber is premoulded or cast into the liquid barrier. The "open" vortex chamber thus-formed is closed by a closure or cover plate which is secured over the open chamber at the upstream side of the barrier, provision being made, in the form of an opening in the closure, for an inlet to the vortex chamber.To ensure a tangential inlet to the vortex chamber, there may additionally be formed in the liquid barrier an open channel which is tangential to and communicates with the vortex chamber formed in the liquid barrier; the closure is then adapted to cover fully the vortex chamber but to cover only partially the said channel whereby liquid may flow into the channel and from there be directed tangentially into the vortex chamber. The closure may be fixed or may be removable, for instance it may be slidable vertically in retaining channels to permit access to the vortex chamber and allow maintenance of the vortex valve.

In a second embodiment of the present invention, the vortex valve may be formed separately and secured in a recess in the liquid barrier with the axis of the vortex valve being substantially perpendicular to the plane of the liquid barrier and the outlet of the vortex valve communicating with the downstream side of the liquid barrier.

In a third embodiment of the present invention, the vortex chamber may extend downstream of the liquid barrier. In this third embodiment, a suitable housing may be secured to the downstream wall of the liquid barrier over an enlarged opening of the barrier to define the vortex chamber. Alternatively, the vortex chamber may be formed downstream of the liquid barrier as part of the liquid barrier, for instance by a casting or moulding technique.

The liquid barrier may be for instance a wall of a road gully and may, for example, be formed of concrete or a metal or plastic material.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings in which: Figures 1 and 2 show a road gully including a liquid barrier and associated vortex valve flow control in accordance with one aspect of the present invention (Figure 2 is a section on the line Il-Il in Figure 1); Figure 3 is an exploded perspective view showing, in detail, the liquid barrier and associated vortex valve illustrated in Figure 1; Figure 4 shows, in cross-section, another embodiment of a liquid barrier and associated vortex valve flow control in accordance with the present invention; Figure 5 illustrates a further embodiment of a liquid barrier and associated vortex valve in accordance with the present invention; ; Figure 6 shows, in cross-section, the liquid barrier and associated flow control of Figure 5; and Figure 7 is a view towards the upstream end wall of the vortex valve shown in Figures 5.

With reference to Figures 1 to 3, there is shown a road gully 1 having a base 2 and an upstanding wall 3 to define a chamber 4 or reservoir. The wall 3 can be considered a liquid barrier 3a since, in use, it is a barrier to the flow of liquid out of the gully 1. In one section of the liquid barrier is provided a recess 5 in which there is situated a vortex valve flow control 6. The recess in the liquid barrier 3a has an opening 5a through which liquid may flow across the barrier 3a and the vortex valve flow control 6 is secured by suitable fixing means 7 in the recess 5 in the liquid barrier 3a in communication with the opening 5a to control passage of liquid through the barrier 3a.

The vortex valve flow control 6 shown is of the type having flat, parallel end walls 8, 8a joined by a side wall 9 which, when viewed from one end has the shape of a logarithmic spiral; these walls 8, 8a form a housing which defines a vortex chamber 10. The side wall section 9 of the housing is provided with an inlet 11 through which, in use, liquid may enter the vortex chamber 6 tangentially in a manner to promote swirl within the vortex chamber 10. The housing is also provided with an outlet 12 at the downstream axial end of the vortex chamber 6, the outlet 12 communicating with a conduit 13 or pipe which extends through the opening 5a in the liquid barrier 3a.It will be noted that the vortex valve flow control 6 does not extend in a direction upstream of the liquid barrier 3a and is therefore protected from damage by equipment which may be dropped or lowered into a position adjacent the liquid barrier 3a.

Although not shown, the upstream end 8 of the housing may be provided with an opening normally closed by a closure, the opening being operable between the closed position and an open position (in which open position liquid may enter the vortex chamber by-passing the inlet 11) preferably by means which are remote from the vortex-valve, as is disclosed in our British Patent No. 2210995.

In use, the gully 1 fills with liquid, for instance water run-off from a highway, and in normal conditions, the level of water will be defined by the bottom of the outlet 11 of the vortex valve 6, thereby providing an air trap to ensure that any noxious gases do not escape into the gully 1 from the sewer downstream of the gully 1. In storm conditions, the vortex valve 6 regulates the flow of liquid out of the gully 1 so that the sewerage system does not become overloaded. Water backs up in the gully 1 providing the necessary pressure head for operation of the vortex valve; as the storm subsides, the level in the gully 1 can return to normal.

In the embodiment shown in Figure 4, which is similar to that of Figures 1 to 3, the upstream end wall 8 of the housing extends beyond the side wall 9 to form a flange 14. The liquid barrier 3a is provided with a large opening 15 to accommodate the vortex valve 6 and a ledge 16 to which the vortex valve may be secured by means of the flange 14. The upstream end wall 8 also includes an opening 17 adjacent the tangential inlet 11 to the vortex chamber 10 to permit the flow of liquid to the vortex chamber 10.

In the embodiment shown in Figures 5 to 7, the vortex chamber 10 is formed wholly within the liquid barrier 3a by a moulding or casting technique in which a recess in the shape of a desired vortex chamber (such as that shown in Figures 1 to 3) is pre-moulded or cast into the liquid barrier 3a. A separate arcuate section 20 is additionally secured in the recess to complete the necessary side wall 9 to the vortex chamber 10 and to define an open channel 21 which is tangential to and communicates with the main vortex chamber 10. Also cast into the barrier 3a is a box 22 adjacent the inlet. The "open" vortex chamber is closed by a closure 23 which is secured by suitable fixing means 24 over the open chamber at the upstream side of the barrier. The closure 23 includes an opening 25 which is aligned with the box 22 cast in the barrier 3a.

Liquid passing through the opening 25 in the closure 23 fills the box 22 and is then directed tangentially into the vortex chamber 10 from where it flows out through axial outlet away from the gully 1 by conduit 13.

Claims

CLAIMS:

1. A liquid barrier having an opening through which liquid may flow across the barrier and an associated vortex valve flow control which is arranged in communication with the opening to control passage of liquid through the barrier, characterised in that the vortex chamber of the vortex valve flow control does not extend in a direction upstream of the liquid barrier.

2. A liquid barrier and associated vortex valve in accordance with claim 1, wherein the vortex chamber is formed or located wholly within the liquid barrier itself.

3. A liquid barrier and associated vortex valve in accordance with claim 1 or 2, wherein the vortex chamber is formed within the liquid barrier by a moulding or casting technique in which a recess in the shape of a desired vortex chamber is pre-moulded or cast into the liquid barrier.

4. A liquid barrier and associated vortex valve in accordance with claim 3, wherein the recess is closed by a closure or cover plate which is secured over the open chamber at the upstream side of the barrier, provision being made, in the form of an opening in the closure, for an inlet to the vortex chamber.

5. A liquid barrier and associated vortex valve in accordance with claim 3 or 4, wherein there is additionally formed in the liquid barrier an open channel which is tangential to and communicates with the vortex chamber formed in the liquid barrier.

6. A liquid barrier and associated vortex valve in accordance with claim 5, wherein the closure is adapted to cover fully the vortex chamber but to cover only partially the said channel whereby liquid may flow into the channel and from there be directed tangentially into the vortex chamber.

7. A liquid barrier and associated vortex valve in accordance with claim 1, wherein the vortex valve is formed separately and secured in a recess in the liquid barrier with the axis of the vortex valve being substantially perpendicular to the plane of the liquid barrier and the outlet of the vortex valve communicates with the downstream side of the liquid barrier.

8. A liquid barrier and associated vortex valve in accordance with claim 1, wherein the vortex chamber extends downstream of the liquid barrier.

9. A liquid barrier and associated vortex valve in accordance with claim 8, wherein a suitable housing is secured to the downstream wall of the liquid barrier over an enlarged opening of the barrier to define the vortex chamber.

10. A liquid barrier and associated vortex valve in accordance with claim 8, wherein the vortex chamber is formed downstream of the liquid barrier, as part of the liquid barrier.

11. A liquid barrier and associated vortex valve in accordance with claim 1, wherein the liquid barrier is a wall of a road gully.

12. A liquid barrier and associated vortex valve substantially as hereinbefore described, with reference to the accompanying drawings.