ELONGATE WEATHER LOUVRE

Abstract

An elongate weather louvre 10 includes a leading longitudinal edge 12, a trailing longitudinal edge 14, and a crown portion 16 on a flow path defined between the leading longitudinal edge 12 and the trailing longitudinal edge 14. Also included is an intermediate portion 18 between the leading longitudinal edge 12 and the crown portion 16. The intermediate portion 18 has a leading surface 20 and a ramped projection 22 forming part of the leading surface 20 configured to direct airflow at least one of towards and over the crown portion 16.

Description

The present invention relates to an elongate weather louvre and particularly, but not necessarily exclusively, to a method of improving entrained moisture extraction upstream of a crown portion of an elongate weather louvre.

It is typically desirable for a building to have permanent or semi-permanent passive ventilation portions. These portions may be the inlet or outlet of an air ventilation duct as part of a heating, ventilation and air conditioning system or for providing natural ventilation to generator rooms. Whilst it is desirable to allow for air and airflow paths to access these portions of the building, the ventilation results in openings in the buildings, subjecting the buildings to moisture such as wind driven rain or humid air.

To prevent or inhibit the ingress of moisture or water, louvres may be used. An example of a known louvre assembly 1 having a plurality of louvres 2 is shown in the flow diagram of FIG. 1. Each louvre 2 is a conventionally elongate strip or blade which is laterally aligned with the opening of the portion of the building to be ventilated and waterproofed.

The known louvre 2 of FIG. 1 has an upwardly directed component 3, which helps to prevent wind driven rain from entering the opening by creating a barrier to it, and a downwardly directed component 4 to direct water which may overcome this barrier downwards and not into the building. The overall profile of the louvre 2 therefore provides a surface for air to move over.

The transition from an upwardly directed component 3 of the known louvre 2 to the downwardly directed component 4 typically creates a Venturi effect. This produces a pressure differential within the airflow path, thus helping to draw more air therethrough. This can be seen by the movement of air, indicated by arrows, in FIG. 1. The darkest arrows, which are shown in red in section X, indicate the fastest moving air along the louvre 2, and this starts at the intermediate portion 5 of the louvre 2 and crests the crown portion 6. The slower velocity air enters the louvre assembly 1 at section Y, and the air speeds up at section Z as it approaches the crown portion 6.

The core airflow speed produced by the known profile of the louvre 2 and the associated Venturi effect is around 3.4 m/s at section X. This core airflow speed carries a certain amount of entrained moisture through such a louvre assembly 1, and thus into a building.

It is an object of the present invention to solve or substantially obviate the aforementioned problems. More particularly, having a louvre profile that reduces the core airflow speed and/or moves or repositions the higher speed portions of the air flow relative to the louvre to thereby improve moisture egress prior to the air entering a building would be highly beneficial.

According to a first aspect of the present invention there is provided an elongate weather louvre comprising: a leading longitudinal edge; a trailing longitudinal edge; a crown portion on a flow path defined between the leading longitudinal edge and the trailing longitudinal edge; and an intermediate portion between the leading longitudinal edge and the crown portion, the intermediate portion having a leading surface and a ramped projection forming part of the leading surface for directing airflow towards and/or over the crown portion.

The structure of the louvre is such that air can flow over at least parts of the surface of the louvre at a reduced speed. This encourages moisture to drop out of or to be expelled from the air before the air moves into the building or associated ducting. This louvre design enables more moisture or entrained precipitation to be extracted from the air on the leading surface. This leads to more water droplets collecting prior to the crown of the louvre, and therefore being discharged at a front or nose of the louvre blade. Less moisture is therefore likely to be carried through the louvre assembly of the present invention, consequently reducing moisture build up within the building and further mitigating the likelihood of damp and mould forming within the air ventilation shafts and/or the structure of the building itself.

Preferably, in an in-use condition, the ramped projection is at least in part below an apex of the crown portion. Beneficially, in an in-use condition, the ramped projection may begin below an apex of the crown portion. Having the ramped projection below the apex of the crown portion promotes a slight change towards the vertical of the airstream or part of the airstream. With a similar louvre installed above, this causes a slight but noticeable increase in backpressure, resulting in a reduction in core airflow speed, and thus a beneficial slowing of a portion of the air flow on the leading surface. With such a slowing of core speed, improved egress of entrained precipitation is achieved.

Advantageously, in an in-use condition, the ramped projection may end below an apex of the crown portion. Having the ramped projection terminating entirely prior to the top of the crown portion shifts the decelerated portion of the airflow more towards the nose of the louvre.

Preferably, in use, the ramped projection of the intermediate portion is configured to promote an air-flow core velocity of less than or equal to 2 m/s. This reduced core velocity value at and/or adjacent to the intermediate portion promotes an increase in the egress of precipitation from the air, so that more water droplets collect prior to the crown of the louvre.

Optionally, an airflow-guide surface of the ramped projection may be concave. Such a curvature assists the slight change in flow direction towards the vertical, resulting in the beneficial pressure gradient and thus the reduction in core airflow speed at this point on the airflow path and prior to the crown portion.

Preferably, the concave airflow-guide surface extends from a leading ramp portion to a free intermediate ramp edge. Having the concaved surface extending over the entire lateral extent of the ramped projection promotes the required change of direction of the portion of the airflow, thus enabling slowing of the flow rate prior to the crown portion.

Beneficially, an in use vertical extent from a trailing ramp edge of the leading ramp portion to the free intermediate ramp edge may be less than or equal to 11 mm. A longer ramped projection promotes an airflow vortex at or adjacent to the trailing edge. This tends to re-accelerate the airflow at or adjacent to the apex of the crown portion.

Optionally, an in use vertical extent from the trailing ramp edge of the leading ramp portion to the free intermediate ramp edge is less than or equal to 1 mm. More preferably, an in use vertical extent from the trailing ramp edge of the leading ramp portion to the free intermediate ramp edge is between 0.65 mm and 0.85 mm. Flow analysis indicates that a lateral extent of ramp of below one millimetre, and more preferably between 0.65 mm and 0.85 mm provides an optimal lower core velocity along the leading surface.

Advantageously, the trailing ramp edge of the ramped projection may be contiguous with the crown portion. In this case, eliminating a ramp overhang increases louvre stiffness both laterally and longitudinally, whilst simplifying manufacturing.

Preferably, a backside ramp surface is below an apex of the crown portion. The position of the backside ramp surface being below the apex of the crown portion shifts the decelerated portion of the airflow more towards the nose of the louvre.

Beneficially, an underside of the ramped projection may overhang at least part of the crown portion. This promotes vortex production at or adjacent to the trailing longitudinal edge of the louvre. This re-accelerates the airflow which has previously been slowed along the leading surface over the crown portion and thus out of the louvre assembly.

Optionally, the crown portion may include a base portion and a wing portion. The wing portion advantageously works in conjunction with the ramped projection to further improve the slowing of the airflow along the leading surface, thus promoting an increase in earlier extraction of entrained precipitation.

Preferably, the base portion is convex. The convex curvature of the upper surface matches or substantially matches a curvature of the wing portion, thereby forming a vortex cavity for the louvre.

Advantageously, the wing portion may be recurved to extend towards or substantially towards the ramped projection. The recurved shape of the wing together with the base portion promotes the above-mentioned vortex cavity, causing resistance to at least a portion of the airflow and thus the beneficial drop in core flow velocity prior to an apex of the crown.

Optionally, in an in-use condition, the ramped projection and the wing portion may be configured to form a high-pressure region on the said flow path that causes a local reduction in airflow speed thereby promoting greater entrained moisture egress at or adjacent to the leading surface of the intermediate portion. The afore-mentioned vortex cavity defined at least in part by the ramped projection and the wing portion enables the high-pressure region to be formed during use.

Beneficially, in an in-use condition, the ramped projection may be configured to move a higher-velocity air-movement portion of the said flow path to or towards an apex of the crown portion, thereby promoting greater entrained moisture egress at or adjacent to the leading surface of the intermediate portion. Dependent on a lateral extent of the ramped projection, a velocity of the airflow may be slowed on a leading surface prior to the crown, and/or may be accelerated at or adjacent to the apex of the crown.

Preferably, the elongate weather louvre further comprises a trailing portion having the trailing longitudinal edge, the trailing portion extending from the wing portion. The trailing portion is also configured to form a trailing vortex region on the said flow path after the apex of the crown portion. This causes a localised pressure change in airflow speed, thus re-accelerating airflow over the crown.

According to a second aspect of the present invention there is provided an elongate weather louvre assembly comprising two or more elongate weather louvres as claimed in any one of the preceding claims. A larger number of the improved louvres can be formed into an assembly, thereby increasing the amount of precipitation expulsion on the leading surfaces as air flows through the assembly.

According to a third aspect of the present invention there is provided a method of improving entrained moisture extraction upstream of a crown portion of an elongate weather louvre, preferably in accordance with the first aspect of the invention, the method comprising the step of providing a ramped projection on an intermediate portion of the louvre, the ramped projection moving a higher-velocity air-movement portion of the flow path to or towards an apex of the crown portion, thereby promoting greater entrained moisture egress at or adjacent to the leading surface of the intermediate portion. With a leading surface of the louvre providing a significantly larger surface area than other parts thereof, causing at least a portion of the airflow to move at a reduced core velocity between a leading nose portion and the crown portion of the louvre blade advantageously allows for greater moisture extraction along that leading surface.

Preferably, the ramped projection is at least in part below an apex of the crown portion. Having the ramped projection below the apex of the crown portion promotes a slight change towards the vertical of the airstream or part of the airstream. With a similar louvre installed above, this causes a slight increase in backpressure, resulting in a reduction in core airflow speed, and thus a beneficial slowing of a portion of the air flow. With such a slowing of core speed, improved egress of entrained precipitation is achieved.

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made by way of example only to the accompanying drawings, in which:

FIG. 1 shows a prior art louvre assembly with in use exterior air flow-paths being shown by way of a plurality of arrows, the lighter the shade of an arrow, otherwise shown as blue or green arrows, indicating the slower the airspeed, and the darker the shade of arrow, otherwise shown as red arrows, indicating the faster airspeed, the highest velocity airspeed being located in section X;

FIG. 2 is a cross sectional view of a first embodiment of an elongate weather louvre, in accordance with a first aspect of the invention;

FIG. 3 is a first embodiment of an elongate weather louvre assembly in accordance with the second aspect of the invention, the elongate weather louvre assembly having a plurality of the elongate weather louvres of FIG. 2, with in use exterior air flow-paths being shown by way of a plurality of arrows, the lighter the shade of an arrow, otherwise shown as blue or green arrows, indicating the slower the airspeed, and the darker the shade of arrow, otherwise shown as red arrows, indicating the faster airspeed, the highest velocity airspeed being located in section A;

FIG. 4 is a cross-sectional view of a second embodiment of the elongate weather louvre, in accordance with the first aspect of the invention;

FIG. 5 is a second embodiment of an elongate weather louvre assembly in accordance with the second aspect of the invention, this elongate weather louvre assembly having a plurality of the elongate weather louvres of FIG. 4, with in use exterior air flow-paths being shown by way of a plurality of arrows, the lighter the shade of an arrow, otherwise shown as blue or green arrows, indicating the slower the airspeed, and the darker the shade of arrow, otherwise shown as red arrows, indicating the faster airspeed, the highest velocity airspeed being located in section E;

FIG. 6 is a cross-sectional view of a third embodiment of the elongate weather louvre, in accordance with the first aspect of the invention;

FIG. 7 is cross section of a third embodiment of an elongate weather louvre assembly in accordance with the second aspect of the invention and having a plurality of the elongate weather louvres as shown in FIG. 6; and

FIG. 8 is an isometric view of the elongate weather louvre assembly of FIG. 7 showing at least a portion of the longitudinal extent of the individual elongate weather louvres.

Referring firstly to FIGS. 2 and 3, there is shown a first embodiment of an elongate weather louvre, referred to as 10. The elongate weather louvre 10 has a leading longitudinal edge 12, a trailing longitudinal edge 14, a crown portion 16 and an intermediate portion 18 between the leading longitudinal edge 12 and the crown portion 16. The intermediate portion 18 has a leading surface 20 and a ramped projection 22 forming part of the leading surface 20.

FIG. 3 shows an elongate weather louvre assembly 100 having, in this case, five of the said elongate weather louvres 10. The elongate weather louvres 10 of the elongate weather louvre assembly 100 are vertically spaced apart from one another but are otherwise laterally aligned. Each elongate weather louvre 10 is preferably attached to a bracket (not show) which is attached to a building.

Each elongate weather louvre 10 is an elongate strip or blade which preferably has an upwardly directed component 24 to help prevent wind driven rain from entering the opening, and a downwardly directed component 26 which directs precipitated water downwards. Each elongate weather louvre 10 is preferably formed via extrusion for ease of manufacture and so that the user can specify the specific lateral extent of the elongate weather louvres 10. Each elongate weather louvre 10 is preferably substantially arcuate.

The leading longitudinal edge 12, or nose, is an edge at an in-use lower end 28 of the elongate weather louvre 10, which provides a ramp for water droplets to slide off. The leading longitudinal edge 12 is at an opposing end of the elongate weather louvre 10 to the trailing longitudinal edge 14. The leading longitudinal edge 12 is preferably below an apex 30 of the trailing longitudinal edge 14 when the elongate weather louvre 10 is in use.

A leading longitudinal portion 32 has the leading longitudinal edge 12, the leading longitudinal portion 32 being convex. The shape of the leading longitudinal portion 32 assists the flow of air onto the intermediate portion 18 of the elongate weather louvre 10. It is feasible that the leading longitudinal portion may not be convex and instead is linear or concave.

The leading longitudinal portion 32 preferably has an in-turned-lip 34 on an in-use lower surface 36 of the elongate weather louvre 10. The in-turned-lip 34 takes the form of a V-shaped recurve being directed towards the crown portion 16, or directed downstream. The leading longitudinal portion 32 thus has an internal surface 38, which faces the crown portion 16 and the direction of airflow, and an external surface 40 which faces away from the crown portion 16 and away from the direction of airflow. This in-turned-lip 34 helps direct airflow onto the elongate weather louvre 10 below in the elongate weather louvre assembly 100 as seen in FIG. 3. It is feasible that the in-turned-lip is not present.

On the in-use lower surface 36 of the elongate weather louvre 10 is preferably at least one spur or projection 42. The spur 42 is preferably spaced apart from the in-turned-lip 34. In FIGS. 2 and 3 there is only shown one spur 42 present. The spur 42, acting as a barrier, assists in reducing the core velocity of the airflow moving over the elongate weather louvre 10 below in the elongate weather louvre assembly 100. This improves the precipitation of water before the crown portion 16. It is feasible that there may be no spur present on the lower surface.

A trailing portion 44 includes the trailing longitudinal edge 14, the trailing portion 44 extending from the crown portion 16. The trailing portion 44 may further comprise an intermediate trailing portion 46 which is located between the crown portion 16 and the trailing longitudinal edge 14. The intermediate trailing portion 46 is preferably convex in shape, although it is possible that it may be linear or concave.

The trailing portion 44 is configured to form a trailing vortex region 48 on the said flow path after an apex 50 of the crown portion 16. The position of the apex 50 of the crown portion 16 is also indicated by a dashed line D1. The airflow travelling over the apex 50 of the crown portion 16 is re-accelerated due to a localised pressure change in airflow speed from the trailing vortex region 48. This is observed in the flow diagram of FIG. 3.

The trailing longitudinal edge 14 is or is preferably substantially perpendicular to the intermediate trailing portion 46. The trailing longitudinal edge 14 is at such an angle so as to provide a substantial attachment means for the elongate weather louvre 10 to attach to the bracket (not shown) attached to the building. The trailing longitudinal edge 14 may also form a water catchment portion 52 with the intermediate trailing portion 46. Water which has precipitated out of the airflow at the crown portion 16 and does not run down the leading surface 20 may collect in the water catchment portion 52 to prevent water entering the building.

The trailing longitudinal edge 14 has a trailing-edge free end 54. An in-use lower surface 56 of the trailing-edge free end 54 has a convex portion 58 which increases the attachment ability of the trailing longitudinal edge 14 to the bracket (not shown).

The crown portion 16 is located between, and contiguous with, a trailing portion 60 of the intermediate portion 18 and the trailing portion 44 of the elongate weather louvre 10. The crown portion 16 is therefore on a flow path defined between the leading longitudinal edge 12 and the trailing longitudinal edge 14.

The crown portion 16 has a base portion 62 and a wing portion 64. The intermediate trailing portion 46 is attached to the crown portion 16 at the interface between the base portion 62 and the wing portion 64 in this embodiment. The base portion 62 is preferably convex in shape, although it is feasible that the base portion may be linear. The convex curvature of an upper surface 66 of the base portion 62 matches or substantially matches a curvature of the wing portion 64, which forms a vortex cavity 68 for the elongate weather louvre 10.

An apex 70 of the base portion 62 is defined as the upper most portion of the base portion 62 when the elongate weather louvre 10 is in use. The position of the apex 70 of the base portion 62 is indicated by a dashed line D2. The apex 70 of the base portion 62 is below the apex 50 of the crown portion 16 when the elongate weather louvre 10 is in use. This offset is shown in FIG. 2 by the dashed lines D1 and D2.

The wing portion 64 preferably extends perpendicularly or substantially perpendicularly from a trailing edge 72 of the base portion 62. The wing portion 64 preferably has a free end 74. The wing portion 64 is preferably recurved to extend towards or substantially towards the ramped projection 22 and so the free end 74 of the wing portion 64 points upstream of the direction of airflow. The wing portion 64 thus has an internal surface 76, which faces the leading longitudinal edge 12 and away from the direction of airflow, and an external surface 78 which faces away from the leading longitudinal edge 12 and towards the direction of airflow.

The extent of the curvature of the recurve is such that a lateral cross-section here is, or is substantially, semi annular. However, it is appreciated that the recurve may in fact be curved to a lesser or greater extent.

The recurved shape of the wing portion 64 together with the base portion 62 deflects the air flowing along the leading surface 20 and promotes the formation of the vortex cavity 68 as shown in FIG. 3, causing resistance to at least a portion of the airflow. The vortex cavity 68 is preferably formed between the in use upper surface 66 of the base portion 62 and the internal surface 76 of the wing portion 64. The vortex cavity 68 includes high pressure air which moves in a vortex, which is indicated by lighter arrows, or blue arrows, in FIG. 3.

The core flow velocity of the airflow is therefore reduced prior to the apex 50 of the crown portion 16 due to the air in the vortex cavity 68. The release of high pressure air from the vortex cavity 68 disrupts the air flowing up the intermediate portion 18 and so reduces the core velocity airflow before moving over the apex 50 of the crown portion 16. This promotes the entrained moisture to precipitate out of the air prior to the crown portion 16.

The apex 50 of the crown portion 16 is defined as the upper most portion of the crown portion 16 when the elongate weather louvre 10 is in use.

The intermediate portion 18 includes the leading surface 20 and the ramped projection 22, which forms part of the leading surface 20. A leading portion 80 of the intermediate portion 18 is preferably contiguously formed with a trailing portion 82 of the leading longitudinal portion 32. The interface between the intermediate portion 18 and the leading longitudinal portion 32 is where the convex shape of the leading longitudinal portion 32 changes to the concave shape of the leading surface 20 of the intermediate portion 18.

The in-use lower surface 36 of the intermediate portion 18 preferably has at least one attachment means 84, or projection 84, which projects from the in use lower surface preferably proximal to the ramped projection 22. Two attachment means 84 are shown on the lower surface in FIGS. 2 and 3, and are configured to attach to the bracket (not shown) attached to the building. The in-use lower surface 36 is preferably convex in shape. The projections 84 assist in reducing the core velocity of the airflow moving over the elongate weather louvre 10 below in the elongate weather louvre assembly 100 and so improves the precipitation of water before the crown portion 16. It is feasible that there may be no projections present on the lower surface.

The leading surface 20 is the surface over which airflow moves. The leading surface 20 is preferably smooth and not discontinuous, however it is possible that the leading surface may have at least one channel therealong to further reduce the core velocity of the airflow as the movement of the air is disrupted. The leading surface 20 of the elongate weather louvre 10 is preferably elongate and therefore provides a large surface area for the air to flow over. At least a portion of the airflow can move at a reduced core velocity between the leading longitudinal edge 12 and the crown portion 16 which allows for greater moisture extraction along the leading surface 20 compared to the trailing portion of the louvre having a smaller surface area.

The ramped projection 22 directs airflow towards and/or over the crown portion 16. In an in-use condition in FIG. 2, the ramped projection 22 is preferably at least in part below the apex 50 of the crown portion 16 and begins below the apex 50 of the crown portion 16. Having the ramped projection 22 below the apex 50 of the crown portion 16 promotes a slight change towards the vertical of the airstream or part of the airstream. With a similar elongate weather louvre 10 installed above, this causes a slight but noticeable increase in backpressure, resulting in a reduction in core airflow speed, and thus a beneficial slowing of a portion of the airflow on the leading surface 20. With such a slowing of core speed, improved egress of entrained precipitation is achieved.

The ramped projection 22 is also shown to end below the apex 50 of the crown portion 16 in FIG. 2. This shifts the decelerated portion of the airflow more towards the leading longitudinal edge 12 of the elongate weather louvre 10 and so the entrained precipitation is promoted at the leading longitudinal edge 12 of the elongate weather louvre 10.

The ramped projection 22 of FIGS. 2 and 3 is configured to promote an air-flow core velocity of less than or equal to 2 m/s. Specifically, the core velocity achieved from experimental data is 1.8 m/s. Compared to the prior art, this reduced core velocity value, which is at and/or adjacent to the intermediate portion 18, may promote an increase in the egress of precipitation from the air. In this case, more water droplets can thus be collected prior to the crown portion 16 of the elongate weather louvre 10, resulting in less moisture entering the building.

To help achieve the reduced air-flow core velocity, an airflow-guide surface 86 of the ramped projection 22 may be concave. This curvature causes the airflow to change direction towards the vertical which results in a pressure gradient. The generation of this pressure gradient reduces the airflow speed before the air moves over the crown portion 16.

The ramped projection 22 preferably has a leading ramp portion 88 and a free intermediate ramp edge 90. The concave airflow-guide surface 86 preferably extends from the leading ramp portion 88 to the free intermediate ramp edge 90.

The leading ramp portion may have a channel located along its extent to further disrupt the airflow and thus reduce the core velocity.

The free intermediate ramp edge 90 is located below the apex 70 of the base portion 62 in this embodiment. The position of the free intermediate ramp edge 90 is indicated by a dashed line D3, and the offset between free intermediate ramp edge 90 and the apex 70 is shown in FIG. 2 between the dashed lines D2 and D3. It is feasible that the free intermediate ramp edge is above the apex of the base portion. It is also possible that the free intermediate ramp edge is located above both the apex of the base portion and the apex of the crown portion.

The ramped projection 22 preferably has a backside ramp surface 92 which is below the apex 50 of the crown portion 16. This positioning promotes the decelerated portion of the airflow to be shifted more towards the nose of the elongate weather louvre 10. It is possible that this backside ramp surface may be partially above the apex of the crown portion. The backside ramp surface 92 may be perpendicular to or substantially perpendicular to the leading ramp portion 88 to provide a significant ramp for the air to flow over. The backside ramp surface 92 is preferably below the apex 50 of the crown portion 16.

The ramped projection 22 may further have a trailing ramp edge 94. The trailing ramp edge 94 is at an opposite end of the backside ramp surface 92 to the free intermediate ramp edge 90. The position of the trailing ramp edge 94 is indicated by a dashed line D4.

The interface between the intermediate portion 18 and the base portion 62 is where the trailing ramp edge 94 meets with a leading edge 96 of the base portion 62. In other words, the trailing ramp edge 94 of the ramped projection 22 is contiguous with the crown portion 16.

An in use vertical extent V1 from the trailing ramp edge 94 of the leading ramp portion 88 to the free intermediate ramp edge 90 may be less than or equal to 1 mm and is more preferably between 0.65 mm and 0.85 mm. Specifically, the in use vertical extent V1 of the elongate weather louvre 10 shown in FIGS. 2 and 3 is 0.76 mm which according to flow analysis provides an optimal lower core velocity along the leading surface 20. The in use vertical extent V1 is measured as the distance from the trailing ramp edge 94 to the free intermediate ramp edge 90, otherwise indicated by the offset between dashed lines D3 and D4.

In use, as illustrated by FIG. 3, the air flows between the elongate weather louvres 10 of the elongate weather louvre assembly 100. Although not shown, the elongate weather louvres 10 are attached to brackets which are attached to the building. The trailing longitudinal edge 14 is proximal to the building and the leading longitudinal edge 12 is distal to the building when in use.

Specifically, the air flows along the intermediate portion 18, up over the ramped projection 22 and over the crown portion 16.

The concave shape of the leading surface 20 reduces turbulence effects as the air is directed upwards and promotes laminar flow.

The ramped projection 22 provided on the intermediate portion 18 of each of the elongate weather louvres 10 preferably moves a higher-velocity air-movement portion 98 of the airflow path to or towards the apex 50 of the crown portion 16. This is indicated by the area of darkest arrows, or red arrows in a section A in FIG. 3.

The air flowing over the ramped projection 22 is shifted vertically and thus reduces the core velocity of the airflow. This promotes greater entrained moisture egress at or adjacent to the leading surface 20 of the intermediate portion 18, where the slower air flows, as shown by the lighter arrows, or green and yellow arrows in a section B in FIG. 3.

The higher-velocity air-movement portion 98 may also be referred to as the maximum-velocity air-movement portion 98. In this case, the maximum-velocity air-movement portion 98 contains a portion of the airflow which has a maximum core velocity of 1.8 m/s, as indicated by the red arrows in section A. This is significantly lower than that of the prior art, and notably is repositioned compared to the prior art to be at and over the crown portion 16, and thus further downstream.

The air flowing in section B, shown by the green and orange arrows, has a core velocity between 1 m/s and 1.4 m/s and thus the air speed is shown to slow as it travels along the large surface area of the intermediate portion 18. This reduced air velocity promotes greater entrained moisture egress at or adjacent to the leading surface 20. In the prior art, the air initially travels into the louvre assembly 1 slowly at section Y and then speeds up along section Z. Comparatively, in the present embodiment of the invention, the air velocity is reduced along the intermediate portion 18 at section B promoting greater entrained moisture egress.

In an in-use condition, as shown by FIG. 3, the ramped projection 22 and the wing portion 64 are configured to form a high-pressure region, or vortex cavity 68, on the said flow path that causes a local reduction in airflow speed thereby promoting greater entrained moisture egress at or adjacent to the leading surface 20 of the intermediate portion 18. The vortex cavity 68 is also shown as section C in FIG. 3, where the air preferably has a core velocity of 0.5 m/s.

The local reduction in airflow speed is defined as the reduction in airflow speed at the vortex cavity 68 between the wing portion 64 and the ramped projection 22.

The airflow velocity moving up the leading surface 20 is reduced as the air within the vortex cavity 68 is pushed out of the vortex cavity 68. The release of air from the vortex cavity 68 disrupts the air flowing up the intermediate portion 18 and so reduces the core velocity airflow before moving over the apex 50 of the crown portion 16. This promotes greater egress of water from the airflow before the air enters the building. The prior art, in comparison has a vortex region on the corresponding lower surface of the louvre 2. The airflow moving along the intermediate portion 5 is not disrupted, and so is not slowed by this vortex as there is no opening in the crown portion 6 for the air to flow out of. Instead, the crown portion 6 is a continuous curved member. As the airflow is not slowed to the same extent as the first embodiment, there is less egress of moisture at the intermediate portion 5 in the prior art compared to the present invention.

Additionally, air with entrained moisture is typically heavier than air without entrained moisture, and therefore would be positioned vertically lower within the airflow. Air with less moisture is guided upwards and over the crown portion 16 of the lower elongate weather louvre 10 as moisture egress occurs due to the reduced core velocity.

Referring to FIGS. 4 and 5, there is shown a second embodiment of the elongate weather louvre, referred to as 110. Similar or identical reference numerals to the first embodiment have been used but with 100 added.

The second embodiment of the elongate weather louvre 110 and the use of the elongate weather louvre 110 is similar to the first embodiment, with the differences outlined below.

The elongate weather louvre 110 has a leading longitudinal edge 112, a trailing longitudinal edge 114, a crown portion 116 and an intermediate portion 118 between the leading longitudinal edge 112 and the crown portion 116. The intermediate portion 118 has a leading surface 120 and a ramped projection 122 forming part of the leading surface 120.

The ramped projection 122 of the intermediate portion 118 has a greater in-use vertical extent V10 compared to the first embodiment. The in use vertical extent V10 from the trailing ramp edge 194 of the leading ramp portion 188 to the free intermediate ramp edge 190 may be less than or equal to 11 mm. Specifically, the in use vertical extent V10 is 10.19 mm. This vertical extent V10 is shown by the offset between dashed lines D30 and D40, which is the position of the free intermediate ramp edge 190 and the position of the trailing ramp edge 194 respectively.

It is possible that the in use vertical extent may also feasibly be more than 11 mm, for example less than or equal to 15 mm.

Having an in use vertical extent V10 of less than or equal to 11 mm may be preferable in terms of an improved effect on the egress of moisture from the air flowing over the louvre. Ideally, water is precipitated further upstream, prior to the crown portion 116, and such a vertical extent V10 of the ramped projection 122 appears to achieve this.

As the ramped projection 122 is longer, the ramped projection 122 has an underside 1100. The ramped projection 122 extends towards the free end 174 of the wing portion 164 which provides a direction for the air to flow along. Although not visible, there may be a vortex cavity between the wing portion and the base portion where the core velocity of the airflow is negligible, 0 m/s or less than or equal to 0.4 m/s.

The underside of the ramped projection may overhang at least part of the crown portion. The underside 1100 of the ramped projection 122 may overhang at least a part of the base portion 162 of the crown portion 116, as shown in FIG. 4.

The free intermediate ramp edge 190, positioned at D30, is located above the apex 170 of the base portion 162 and below the apex 150 of the crown portion 116 in this embodiment. This offset is shown in FIG. 4 by dashed lines D10, D20 and D30, where the apex 150 of the crown portion 116 is positioned at D10 and the apex 170 of the base portion 162 is positioned at D20.

The overhang of the ramped projection 122 promotes vortex production at or adjacent to the trailing longitudinal edge 114 of the elongate weather louvre 110. This is referred to as the trailing vortex region 148, also shown as section D in FIG. 5. This re-accelerates the airflow which has previously been slowed along the leading surface 120 over the crown portion 116 and thus out of the elongate weather louvre assembly 200. The core velocity of the air in section D, the blue arrows in the trailing vortex region 148, is 0.4 m/s. The reduction in airflow velocity, therefore, promotes egress of moisture at the water catchment portion 152 before the air enters the building. The prior art, in comparison, does not have such a trailing vortex region 148 and so there is no reduction of air speed at this portion in the prior art.

The in use vertical extent V20 from the leading longitudinal edge 112 to the free intermediate ramp edge 190 may be less than or equal to 80 mm. Specifically, the vertical extent V20 is 76.87 mm. This vertical extent V20 is shown by the offset between dashed lines as shown by D30 and D50, which is the position of the free intermediate ramp edge 190 and the position of the leading longitudinal edge 112 respectively.

In use, due to the increased length of the ramped projection 122, the maximum-velocity air-movement portion 198 is shifted further downstream and over the crown portion 116 compared to the first embodiment. The maximum-velocity air-movement portion 198 is shown by a section E in the airflow diagram of FIG. 5.

The core velocity of the air in section E is 3.4 m/s. Although this is the same value of the core air velocity of the prior art, the maximum-velocity air-movement portion 198 of the present embodiment is shifted further downstream and over the crown portion 116 compared to the prior art. This shift downstream promotes egress of moisture at the intermediate portion 118 as the lower velocity air travelling between 1 m/s and 2.1 m/s, shown by the yellow arrows in section G, is prior to the crown portion 116.

Due to the blade profile of this embodiment, the air flow velocity is slowed as it approaches section G in FIG. 5, and so improved egress of moisture from the air occurs at and/or adjacent to section G along the intermediate portion 118.

The elongate weather louvres 210 of the elongate weather louvre assembly 200 of FIG. 5 are vertically spaced apart from one another but are otherwise laterally aligned.

Referring to FIGS. 6, 7 and 8 there is shown a third embodiment of the elongate weather louvre, referred to as 210. Similar or identical reference numerals to the first embodiment have been used but with 200 added.

The third embodiment of the elongate weather louvre 210 and the use of the elongate weather louvre 210 is similar to the first embodiment, with the differences outlined below.

The elongate weather louvre 210 has a leading longitudinal edge 212, a trailing longitudinal edge 214, a crown portion 216 and an intermediate portion 218 between the leading longitudinal edge 212 and the crown portion 216. The intermediate portion 218 has a leading surface 220 and a ramped projection 222 forming part of the leading surface 220.

The intermediate trailing portion 246 is preferably attached to the wing portion 264 of the crown portion 216. The intermediate trailing portion 246 is preferably attached to the wing portion 264 above the apex 270 of the base portion 262. The intermediate trailing portion 246 is preferably attached to the wing portion 264 below the apex 250 of the crown portion 216. The intermediate trailing portion 246 is thus preferably attached to the wing portion 264 between the apex 270 of the base portion and the apex 250 of the crown portion 216. This arrangement strengthens the structure of the elongate weather louvre 210. The intermediate trailing portion 246 is preferably linear in shape, although it is possible that it may be convex or concave.

The in use vertical extent V100 from the trailing ramp edge 294 of the leading ramp portion 288 to the free intermediate ramp edge 290 may be less than or equal to 1 mm. Specifically, the in use vertical extent V100 is 0.76 mm.

The position of the free intermediate ramp edge 290 is indicated by a dashed line D300. The position of the trailing ramp edge 294 is indicated by a dashed line D400. The in use vertical extent V100 is measured as the distance from the trailing ramp edge 294 to the free intermediate ramp edge 290, otherwise indicated by the offset between dashed lines D300 and D400.

An in use vertical extent V200 from the leading longitudinal edge 212 to the free intermediate ramp edge 290 may be less than or equal to 70 mm, which is the same as the corresponding in use vertical extent of the first embodiment. Specifically, the in use vertical extent V200 may be 67.44 mm, which is the same as the corresponding in use vertical extent of the first embodiment.

This vertical extent V200 is shown by the offset between dashed lines as shown by D300 and D500, which is the position of the free intermediate ramp edge 290 and the position of the leading longitudinal edge 212 respectively.

The in use horizontal extent H100 from the leading longitudinal edge 212 to the trailing-edge free end 254 is preferably less than or equal to 130 mm. More preferably, the in use horizontal extent H100 from the leading longitudinal edge 212 to the trailing-edge free end 254 is preferably less than or equal to 125 mm. More preferably, the in use horizontal extent H100 is preferably 124.21 mm. It is feasible that the in use horizontal extent may be greater than 130 mm, for example 150 mm or 200 mm.

The free intermediate ramp edge 290 is located below the apex 270 of the base portion 262, located at D200, and below the apex 250 of the crown portion 216, located at D100, in this embodiment. It is feasible that the free intermediate ramp edge is above the apex of the base portion. It is also possible that the free intermediate ramp edge is located above the apex of the base portion and the apex of the crown portion.

FIG. 7 shows an elongate weather louvre assembly 300 in an in use configuration having elongate weather louvres 210 of the third embodiment. The elongate weather louvres 210 are vertically spaced apart from one another but are otherwise laterally aligned.

FIG. 8 shows an isometric view of the elongate weather louvre assembly 300 having elongate weather louvres 210 of the third embodiment, showing an example of the lateral extent of the elongate weather louvres 210. It is feasible that the lateral extent of the elongate weather louvres may be larger or smaller than that shown in FIG. 8.

The large surface area of the leading surface 220 is also visible in FIG. 8, the large surface area providing a greater distance for the air to flow over which slows the air down. The reduction in core velocity due to this large surface area leads to a greater egress of moisture towards the leading longitudinal edge 212.

The ramped projection 222 is shown as a ledge in this view, which may be able to hold a small volume of precipitated water therein, to further reduce the core velocity of the flowing air as the water provides further resistance to the airflow.

It is therefore possible to provide an elongate weather louvre and an elongate weather louvre assembly which reduces the core velocity of air flowing into a building, such that there is improved egress of moisture from the air prior to the crown portion of the elongate weather louvre.

The words ‘comprises/comprising’ and the words ‘having/including’ when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps, or components, but do not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.

The embodiments described above are provided by way of example only, and various changes and modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims

1. An elongate weather louvre comprising:

a leading longitudinal edge;

a trailing longitudinal edge;

a crown portion on a flow path defined between the leading longitudinal edge and the trailing longitudinal edge; and

an intermediate portion between the leading longitudinal edge and the crown portion, the intermediate portion having a leading surface and a ramped projection forming part of the leading surface configured to direct airflow at least one of towards and over the crown portion.

2. The elongate weather louvre as claimed in claim 1, wherein, in an in-use condition, the ramped projection is at least in part below an apex of the crown portion.

3. The elongate weather louvre as claimed in claim 1, wherein, in an in-use condition, the ramped projection begins below an apex of the crown portion.

4. The elongate weather louvre as claimed in claim 1, wherein, in an in-use condition, the ramped projection ends below an apex of the crown portion.

5. The elongate weather louvre as claimed in claim 1, wherein in use, the ramped projection of the intermediate portion is configured to promote an air-flow core velocity of less than or equal to 2 m/s.

6. The elongate weather louvre as claimed in claim 1, wherein an airflow-guide surface of the ramped projection is concave and wherein the concave airflow-guide surface extends from a leading ramp portion to a free intermediate ramp edge.

7. The elongate weather louvre as claimed in claim 6, wherein an in use vertical extent from a trailing ramp edge of the leading ramp portion to the free intermediate ramp edge is less than or equal to 11 mm.

8. The elongate weather louvre as claimed in claim 7, wherein an in use vertical extent from the trailing ramp edge of the leading ramp portion to the free intermediate ramp edge is less than or equal to 1 mm.

9. The elongate weather louvre as claimed in claim 8, wherein an in use vertical extent from the trailing ramp edge of the leading ramp portion to the free intermediate ramp edge is between 0.65 mm and 0.85 mm.

10. The elongate weather louvre as claimed in claim 1, wherein a backside ramp surface is below an apex of the crown portion.

11. The elongate weather louvre as claimed in claim 1, wherein an underside of the ramped projection overhangs at least part of the crown portion.

12. The elongate weather louvre as claimed in claim 1, wherein the crown portion includes a base portion and a wing portion.

13. The elongate weather louvre as claimed in claim 12, wherein the base portion is convex.

14. The elongate weather louvre as claimed in claim 13, wherein the wing portion is recurved to extend towards the ramped projection.

15. The elongate weather louvre as claimed in claim 12, wherein, in an in-use condition, the ramped projection and the wing portion are configured to form a high-pressure region on the said flow path that causes a local reduction in airflow speed thereby promoting greater entrained moisture egress at or adjacent to the leading surface of the intermediate portion.

16. The elongate weather louvre as claimed in claim 12, wherein, in an in-use condition, the ramped projection is configured to move a higher-velocity air-movement portion of the said flow path to or towards an apex of the crown portion, thereby promoting greater entrained moisture egress at or adjacent to the leading surface of the intermediate portion.

17. The elongate weather louvre as claimed in claim 12, further comprising a trailing portion having the trailing longitudinal edge, the trailing portion extending from the wing portion.

18. The elongate weather louvre assembly comprising two or more elongate weather louvres as claimed in claim 1.

19. A method of improving entrained moisture extraction upstream of a crown portion of an elongate weather louvre as claimed in claim 1, the method comprising the step of providing a ramped projection on an intermediate portion of the louvre, the ramped projection moving a higher-velocity air-movement portion of the flow path to or towards an apex of the crown portion, thereby promoting greater entrained moisture egress at or adjacent to the leading surface of the intermediate portion.

20. The method as claimed in claim 19, wherein the ramped projection is at least in part below an apex of the crown portion.