WO2017137620A1

WO2017137620A1 - A fluid actuated vent

Info

Publication number: WO2017137620A1
Application number: PCT/EP2017/053130
Authority: WO
Inventors: James Smyth; Peter Smyth; David Smyth; Gerard Smyth; Andrew Smyth
Original assignee: New World Energy Enterprises Ltd
Priority date: 2016-02-12
Filing date: 2017-02-13
Publication date: 2017-08-17
Also published as: GB201602580D0; GB2547264A

Abstract

The present invention provides a fluid actuated vent, for example a vent for terminating a ventilation duct or the like, and being arranged to both passively prevent the ingress of rain while simultaneously effecting the active ejection of any rain which enters the vent, the vent comprising an array of baffles spaced from one another to define a flow channel between adjacent pairs of baffles through which channels fluid can flow through the vent, the baffles being shaped to generate a vortex within each of the flow channels which will act to drive rain from the vent.

Description

A fluid actuated vent

Field of the invention

The present invention is concerned with a fluid actuated vent, for example a vent for terminating a ventilation duct or the like, or for closing an opening along the duct, the vent providing a means to prevent ingress to the duct, for example to precipitation or the like, and actively displacing fluid and any precipitation entrained in the fluid out of the vent.

Background of the invention

Vents used in the termination of a ventilation duct or the like, or an opening along such a duct, in particular but not exclusively when used to provide weatherproofing in an external environment, are commonly of louvered design. This type of vent generally comprises a number of parallel horizontal and partially overlapping slats which, in use, slope downwardly from an upper to a lower edge. This configuration allows rain or other precipitation to fall onto the outer face of the vent and drain downwardly over successive slats and away from the opening, which thus provide an effective barrier to the ingress of rain while still allowing gas to be exhausted through the vent. This type of conventional louvered vent thus provides a purely passive barrier to rain or other precipitation, which may not provide adequate protection in the event of strong winds or the like which can act to drive rain upwardly between the slats of the vent. While such vents essentially provide weatherproofing to the above mentioned duct or opening, they can often restrict the free flow of exhaust air, gas or other fluid through the ventilation duct or opening. A vent may often have to favour one functionality over another in overall design, either allowing free flow through the vent at the expense of weatherproofing, or vice versa. It is therefore an object of the present invention to provide a vent which seeks to address the above mentioned issues.

Summary of the invention

According to the present invention there is provided a fluid actuated vent comprising a first face, an opposed second face, and at least a pair of baffles spaced from one another to define a flow channel between the pair of baffles through which fluid can flow between the first and second faces;

characterised in that one or more of the baffles are shaped to direct fluid travelling through the respective flow channel against an adjacent baffle in order to generate a vortex within the flow channel in response to the flow of fluid between the faces. Preferably, the one or more baffles are arranged to accelerate the fluid within the vortex so as to establish a pressure differential between the flow channel and an exterior of the vent. Preferably, the one or more baffles are shaped such that the vortex rotates in a direction which accelerates fluid from the second face to the first face.

Preferably, the one or more baffles comprise a lower edge and an upper edge, each baffle having a curved lip terminating at the upper edge such that the upper edge faces a lower surface of an adjacent baffle.

Preferably, the slope of the baffle reverses between the lower and the upper edge,

Preferably, the one or more baffles define a convergent divergent profile converging inwardly from the lower edge towards a throat and diverging outwardly from the throat towards the upper edge.

Preferably, at least a divergent portion of the baffle has a curved profile.

Preferably, the baffles define a flow path that is oblique with respect to a plane of the first and second faces.

Preferably, the plurality of baffles are provided in a louvered arrangement.

Preferably, the vent comprises a frame surrounding at least one of the faces.

Preferably, the frame defines a flow augmentor.

Preferably, the frame defines a shroud for fluid flow in one direction between the faces and a diffuser for fluid flow in the other direction.

Preferably, one or more of the baffles comprise one or more apertures to permit fluid to flow from the flow channel through the aperture.

As used herein, the term "vent" is intended to mean a cover through which a fluid, for example air, can flow, the cover being used to close or terminate an opening in a surface such as a wall or the like or at the terminal end of a ventilation duct, etc.

Brief description of the drawings

The present invention will now be described with reference to the accompanying drawings, in which; Figure 1 illustrates a perspective view of a fluid actuated vent according to an embodiment of the present invention; Figure 2 illustrates a front elevation of the vent shown in Figure 1 ;

Figure 3 illustrates a sectioned side of the vent shown in Figures 1 and 2;

Figure 4 illustrates an enlarged view of a portion of the vent as shown in Figure 3; and

Figure 5 illustrates a plan view of the vent shown in the previous Figures, with a ventilation duct shown in broken lines.

Detailed description of the drawings

Referring now to the accompanying drawings there is illustrated a fluid actuated vent, generally indicated as 10, for particular but not exclusive use in terminating a ventilation duct D (shown in Figure 5). The vent 10 provides both a protective cover about the end of the duct D for keeping out precipitation and bird or animal life, while also effecting the active displacement of fluid, for example air, from within the duct D through the vent 10 to the exterior, as will be described in detail hereinafter. The process of actively displacing fluid such as air from the vent 10 will also actively displace any precipitation that may have been driven into flow channels 18, for example by strong wind or the like, as this precipitation will become entrained within the air in the flow channels 18. The vent 10 is thus particularly intended to be used in exterior environments where the vent 10 will be exposed to wind and rain.

The vent 10 comprises an array of baffles 12 which are preferably arranged in essentially parallel spaced relationship to one another in order to define a louvered configuration. When mounted in position at the termination of the ventilation duct D or other location, the baffles 12 extend in a substantially horizontal orientation across the width of the vent 10. The vent 10 has a first or outer face 14 and an opposed second or inner face 16, the baffles 12 defining a plurality of flow channels 18 between adjacent baffles 12 and through which fluid such as air can flow between the first and second faces 14, 16.

In use the first face 14 faces an exterior, for example the outside environment, while the second face 16 faces into the interior of the duct D. In used the primary flow of fluid across the vent 10 is intended to be in the direction from the second face 16 to the first face 14, for example a fluid being exhausted from a remote location through the ventilation duct D to the exterior environment. It will however be appreciated that the vent 10 may simply be used to provide a covering across an opening in a surface or structure such as a wall or the like, in order to allow ventilation between either side of the structure and the other.

Each of the baffles 12 has a thin planar form, with an upper surface 20 and an opposed lower surface 22, each of the baffles 12 extending between a lower edge 24 and an upper edge 26. The baffles 12 are arranged, when in a working orientation, to slope obliquely upward from the lower edge 24 located adjacent the first face 14 toward the upper edge 26 located adjacent the second face 16, which arrangement provides a physical barrier to the ingress of precipitation or the like, with precipitation such as rain cascading down from one baffle 12 to the next due to the upwardly sloping orientation of each baffle 12. The baffles 12 preferably overlap when viewed horizontally, such that the lower edge 24 of one baffle 12 extends vertically down beyond the upper edge 26 of the adjacent lower baffle 12. This provides passive weatherproofing against rain or other precipitation which may be being driven horizontally by strong winds or the like. As a result the flow channels 18 slope upwardly from the outer face 14 to the inner face 16.

However the baffles 12 are shaped or profiled such that the slope of the baffle 12 reverses between the lower edge 24 and the upper edge 26, as can be clearly seen in the sectioned view of Figure 3, in which the slope of each baffle 12 is reversed at the upper edge 26 relative to the slope at the lower edge 24, such that each baffle 26 has a curved region or lip which terminates at the upper edge 26. In this way the upper edge 26 faces back towards the outer face 14 and thus also faces towards the lower surface 22 of the upper adjacent baffle 12. The baffles 12 can thus be defined as having a convergent divergent profile or shape, converging from the lower edge 24 towards a throat 28 before diverging back outwardly towards the upper edge 26. The throat 28 can thus be defined as an inflection point being the point at which the slope of the baffle 12 reverses between the lower edge 24 and the upper edge 26.

The baffle 12 is preferably curved, at least in the region of the throat 28 and outwardly to the upper edge 26, in order to minimise the generation of turbulence and boundary layer separation as fluid such as air flows along the upper surface 20 of each baffle 12, before being deflected by the reversal in slope at the throat 28 and upper edge 26. However the portion of the baffle 12 between the lower edge 24 and the throat 28 may also have a shallow curvature in order to again reduce turbulence and boundary layer separation in deflecting the fluid flow, as hereinafter described.

Thus in use with the vent 10 positioned as a closure within the mouth of the duct D, or any other suitable location, the outer face 14 will face the external environment and will normally be exposed to moving air flow incident thereon, for example from wind or the like. While the louvered arrangement of the baffles 12 will deflect a significant proportion of this incident air flow, a proportion will enter each of the flow channels 18 defined between adjacent baffles 12. This airflow or other fluid flow will then travel upwardly from the first face 14, through the flow channel 18 towards the second face 16. However as the airflow reaches the throat 28 it will be deflected as a result of the reversal of the slope of the baffle 12, before flowing off the upper edge 26. The airflow will thus have been redirected towards the lower surface 22 of the upper adjacent baffle 12, which will act to further redirect the airflow back in the direction of the outer face 14.

This deflection will result in the generation of a localised vortex within the respective flow channel 18 in the area about the upper edge 26. From the perspective of Figures 3 and 4 this vortex will be rotating in a counter clockwise direction. The vortex will act to accelerate the airflow entrained therein, thereby reducing the pressure of the air or other fluid within the flow channel 18, and thereby resulting in a pressure differential between the flow channel 18 and the inner face 16. This pressure differential will act to positively displace fluid from the interior of the duct D, adjacent the inner face 16, through the flow channels 18 to be exhausted from the vent 10 via the outer face 14. It will be appreciated that the vent 10 will result in the generation of multiple vortices, one in each of the flow channels 18, thereby actively exhausting fluid across substantially the full height and width of the vent 10. In addition to actively exhausting fluid from within the duct D the vortices generated within the flow channels 18 will also entrain any precipitation such as rain or the like which may be driven upwardly through the flow channels 18 by the wind or other incident airflow blowing against the outer face 14. This entrained precipitation will then be exhausted back out of the flow channels 18 as a result of the above mentioned pressure differential generated between the inner face 16 and the flow channels 18. As a result the vent 10 provides an active means of ejecting or displacing rain from the interior of the vent 10, and the stronger the wind the higher the velocity of the vortices generated and consequently the greater the rain ejection action.

In order to provide an additional source of air flow to feed and maintain the vortices, the baffles 12 are preferably provided with one or more, and preferably an array of openings 30, preferably located adjacent the lower edge 24 of the respective baffle 12, which provide ports through which exterior air flow may be drawn into the flow channels 18 to become entrained in the vortices. Any precipitation that passes through the openings 30 will simply fall downwardly onto the adjacent baffle 12, or if entrained within the airflow within the flow channel 18 will ultimately be exhausted back out the first face 14 as a result of the action of the vortices.

In the embodiment illustrated the vent 10 comprises a substantially rectangular frame 32

circumscribing and supporting the array of baffles 12 in substantially conventional form. An array of parallel rod like supports 34 extend across the width of the frame 32, onto which the baffles 12 may be clipped or otherwise secured, although it will be appreciated that any other suitable means of securing the baffles 12 to the frame 32 may be employed.

The frame 32 is adapted to augment the air or other fluid flowing into or out of the vent 10, funnelling air flow towards the outer face 14 in order to assist in the generation of the vortices within the flow of channels 18, which in the embodiment illustrated is achieved by shaping the frame 32 to flare outwardly in the form of a rectangular funnel. Conversely this flared frame 32 acts as a diffuser to air flowing out of the first face 14, thereby reducing the pressure of said airflow and thus increasing the pressure differential relative to the second face 16 to further drive fluid flow through the vent 10. It is however to be understood that the frame 32 could be of a standard shape or profile which would sit flush with the surrounding duct D or surface in which the vent 10 is installed. It should also be understood that the vent 10 could be produced without any frame 32, or conversely a frame 32 could additionally be provided about the inner face 16.

In the absence of wind or other fluid flow acting against the outer face 14, the fluid to be exhausted from the duct D will approach the inner face 16 and will initially encounter the throat 28 of each of the baffles 12, which will thus act to divide the airflow, with a portion flowing upwardly over the upper edge 26 and a portion flowing downwardly into the flow channel 18 below. The airflow that is deflected upwardly over the upper edge 26 will then be directed against the lower surface 22 of the upper adjacent baffle 12, which will deflect the airflow back downwardly into the flow channel 18, thus again establishing a vortex within the flow channel 18. As a result a vortex will be generated in each of the flow channels 18, which will again accelerate the airflow and establish a pressure differential between the flow channels 18 and the inner face 16 which will serve to actively displace fluid from the duct D through the flow channels 18 to exit the outer face 14.

It will thus be appreciated that the vent 10 of the present invention provides a simple alternative to a conventional louvered vent cover (not shown) which remains of simple design devoid of moving parts but which nevertheless is adapted to both passively and actively displace rain or other precipitation from the vent.

Claims

A fluid actuated vent comprising a first face, an opposed second face, and at least a pair of baffles spaced from one another to define a flow channel between the pair of baffles through which fluid can flow between the first and second faces; characterised in that one or more of the baffles are shaped to direct fluid travelling through the respective flow channel against an adjacent baffle in order to generate a vortex within the flow channel in response to the flow of fluid between the faces.

A fluid actuated vent in which the one or more baffles are arranged to accelerate the fluid within the vortex so as to establish a pressure differential between the flow channel and an exterior of the vent.

A fluid actuated vent according to claim 1 in which the one or more baffles are shaped such that the vortex rotates in a direction which accelerates fluid from the second face to the first face.

A fluid actuated vent according to any preceding claim in which the one or more baffles comprise a lower edge and an upper edge, each baffle having a curved lip terminating at the upper edge such that the upper edge faces a lower surface of an adjacent baffle.

A fluid actuated vent according to claim 4 in which the slope of the baffle reverses between the lower and the upper edge.

A fluid actuated vent according to claim 4 in which the one or more baffles define a convergent divergent profile converging inwardly from the lower edge towards a throat and diverging outwardly from the throat towards the upper edge.

A fluid actuated vent according to claim 6 in which at least a divergent portion of the baffle has a curved profile.

8. A fluid actuated vent according to any preceding claim in which the baffles define a flow path that is oblique with respect to a plane of the first and second faces.

A fluid actuated vent according to any preceding claim in which the plurality of baffles provided in a louvered arrangement.

10. A fluid actuated vent according to any preceding claim comprising a frame surrounding at least one of the faces.

1 1. A fluid actuated vent according to claim 10 in which the frame defines a flow augmentor.

12. A fluid actuated vent according to claim 1 1 in which the frame defines a shroud for fluid flow in one direction between the faces and a diffuser for fluid flow in the other direction.

13. A fluid actuated vent according to any preceding claim in which one or more of the baffles comprise one or more apertures to permit fluid to flow from the flow channel through the aperture.