US20120204497A1 - Airstream deflection system for outdoor areas - Google Patents

Abstract

A shielding system that mitigates the effects of wind on an open-air venue by at least partially deflecting wind flow over the field. The shielding system includes shielding modules in abutment around the periphery of the field, each module including an upright member and a horizontal member. The upright member is curvilinear and projects inward toward the field, while the horizontal member is generally planar, mounted at the lower end of the upright member, and it also projects inward. The upright member and the horizontal member define a closed trap zone. An impinging airstream encounters the convex upwind side of the shielding system and is lifted over the field. At the downwind side of the shielding system, the airflow pressure against the closed trap zones produces a region of high pressure, deflecting the airflow over the downwind side of the shielding system.

Description

FIELD OF THE INVENTION
• The present disclosure deals generally with weather protection systems, and more particularly with wind shielding systems around outdoor areas.
BACKGROUND OF THE INVENTION
• Most open-air venues such as playing fields and stadiums for outdoor games, open air theatres, concert venues, and the like are generally drastically affected by wind. Substantial momentum and high turbulence in a blowing airstream often creates undesirable annoyance in such open roof event venues. As an example, at a soccer field, high winds have sufficient momentum to substantially deflect the ball, thus affecting the game and the players' performance. As a further example, cricket matches occur in open-air grounds and many times winds create unwanted interruptions in the game. During open-air concerts and cultural events, this problem becomes persistently troubling when the event occurs on a windy day. Many large swimming pools are located in the open, and a blowing wind can not only annoy the pool patrons, but it can also carry unwanted dust and debris.
• Although efforts have been continuously made to minimize the effects of wind on open-air venues, none of these efforts has been successful in substantially mitigating wind effects. Most of the past and the current wind shielding systems employ only a single surface, and the structures have not been effective in preventing wind. Thus, a need exists for an effective system to shield outdoor venues from wind effects.
SUMMARY
• The present disclosure is directed to a shielding system around a field that mitigates the effects of wind on the field by at least partially deflecting the flow over the field. The shielding system utilizes the collaborative effect of two surfaces that redirect the wind flow over the field, largely preventing them from impacting the surface region. At the same time, the shielding system would facilitate the operation of air-conditioning systems at and around the field surface. The system further substantially reduces the wind turbulence at the field level.
• In one aspect, a shielding system for a field is provided which includes a plurality of upright members mounted in mutual abutment adjacent to the field. Each upright member is curvilinear in form and has a distal end that projects inwardly into the field. A horizontal member is associated with each upright member and is mounted at a lower end of the associated upright member. The horizontal member also projects inwardly into the field. The connection between the upright member and the horizontal member defines a closed end that blocks airflow between them. The curvilinear upright member further has a concave surface and a convex surface. The concave surface faces the field and the convex surface is configured to face airstreams impinging on the field. Further, the upright member projects at least partially over the horizontal member in a manner that defines a partially opened space (trap zone) facing the field, between the horizontal member and the upright member.
• In another aspect, a shielding system for a field is disclosed which includes multiple shielding modules disposed adjacent to the field, and preferably around the periphery of the field. Each of the shielding modules includes a frame, an upright member and a horizontal member associated with the upright member, the horizontal member and the upright member being both mounted over the frame. The upright member is curvilinear in form and lies adjacent to the field in a mounted position, in a manner that it projects inwardly toward the field. The horizontal member preferably has a substantially flat surface. Further, the horizontal member of each shielding module is connected to a lower end of the associated upright member of the shielding module. The connection between the horizontal member and the upright member defines a trap zone between them that deflects impinging airstreams over the field. The upright member presents a concave surface and a convex surface such that when the shielding module is disposed over a peripheral surface of the field, the concave surface faces the field and the convex surface faces airstreams impinging into the field and tending to penetrate therein. The impinging airstream strikes the convex surface of the upright members of shielding modules located at the upstream side, and is redirected to flow along the curvature of the upright members. The redirected airstream strikes the trap zones of the shielding modules located at the downstream side, and creates a high pressure region within those trap zones.
• Advantages of the ‘Coanda effect’ have been utilized in the disclosed shielding system. According to Coanda effect, when a freely flowing airstream experiences an obstructing surface in its path, the stream has a tendency to stick to the surface and follow its curvature, rather than continuing its straight line flow. The impinging airstream encounters an upright member which is an integral part of the shielding modules that constitute the shielding system around the field, and the airflow follows the curvature of the upright member, raising the altitude of the airstream so that it flows over the field. Further, the elevated stream creates high pressure regions in the shielding modules disposed at the downwind side of the field, and these regions act as a barrier, deflecting the airstream upward and over the downwind side of the shielding system. In this manner, the impact of wind on the field is minimized, allowing participants and spectators to perform and watch in a congenial environment.
• Additional features and advantages of the invention will be made apparent from the following detailed description of illustrative embodiments that proceed with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
• The summary above, as well as the following detailed description of preferred embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, exemplary constructions of the invention are shown in the drawings. The invention is not limited to the specific methods and instrumentalities disclosed however. Moreover, those skilled in the art would understand that the drawings are not to scale. Wherever possible, like elements are indicated by identical reference numerals.
• FIG. 1 is an exemplary assembled view of a shielding module in accordance with the present disclosure.
• FIG. 2 illustrates the different components of a frame used in conjunction with the shielding module ofFIG. 1.
• FIG. 3 shows the exemplary shielding module ofFIG. 1 in disassembled form.
• FIG. 4 depicts a typical trap zone between the upright member and the horizontal member of an assembled shielding module of the present disclosure.
• FIG. 5 illustrates a portion of the shielding system of the present disclosure.
• FIG. 6 shows another portion of the shielding system of the present disclosure.
• FIG. 7 illustrates a complete shielding system of the present disclosure, installed at an outdoor sports venue.
• FIG. 8 illustrates the flow path of an airstream tending to impinge on a field and being subsequently deflected over the field by the shielding system.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
• The description below illustrates embodiments of the claimed invention to those of skill in the art. This description illustrates aspects of the invention but does not define or limit the invention, such definition and limitation being contained solely in the claims appended hereto. Those of skill in the art will understand that the invention can be implemented in a number of ways different from those set out here, in conjunction with other present or future technologies.
• The claimed invention discloses a wind shielding system to be installed adjacent to and preferably over the boundaries of a playing field (or any open-air venue) to prevent or minimize impact of wind on the playing field. Here, the term “field” will be used to refer to any outdoor playing field or other venue, lacking a roof. Activities on the field will thus remain unaffected by the wind. Moreover, the air close to the field itself will remain relatively still. This result may further help in conditioning the air around the field in cases where air-conditioning is desired.
• The shielding system of the present disclosure is made up of multiple identical shielding modules, mounted in abutment around the field's periphery surface to protect the field from wind flowing from any direction. Shielding modules can be assembled and mounted employing suitable construction methods known to the art.
• Each shielding module includes two elements. An upright member is curvilinear in form and is mounted at the periphery of the field, with its upper end projecting inward toward the field. Thus, the upright member presents its convex surface toward any oncoming wind, deflecting the flow upward. A horizontal member is associated with the upright member, and it is mounted at the lower end of the upright member in a manner that it projects towards the field. The connection between the upright member and the horizontal member defines a closed end which blocks the passage of air. The two members define a trap zone between them, and any oncoming wind will compress the air within the trap zone, creating a zone of higher pressure within.
• A number abutting shielding modules form a shielding system, mounted around the outer periphery of the field. An oncoming wind impinging on the shielding system encounters the convex surface of the upright members, and the wind flow is deflected upward. At the downwind side of the field, the wind acts on the trap zone to produce a region of high pressure, further deflecting the airflow upwards and away from the field itself
• FIG. 1 shows an exemplaryassembled shielding module100. As illustrated, theshielding module100 includes anupright member120 and ahorizontal member130. Theupright member120 is positioned generally vertically, and is curvilinear in form. Thehorizontal member130 projects inward toward the field, mounted at the lower end of its associated upright member. Theupright member120 and thehorizontal member130 are mounted over aframe110. Details of the upright and horizontal members are set out below, in connection withFIG. 4.
• Constructional aspects of the shielding system are shown inFIGS. 2 and 3. As seen there, theframe110 includes a pair of front supporting legs112(a) and112(b) and a pair of back supporting legs114(a) and114(b). Two horizontal bars116(a) and116(b) connect the front supporting legs to the back supporting legs and provide stability to the frame. In a preferred embodiment, the horizontal bars are welded to the front supporting legs112(a) and112(b) and the back supporting legs114(a) and114(b). The front supporting legs112(a) and112(b), and the back supporting legs114(a) and114(b) are aligned vertically with respect to ground to a certain height and are connected to a pair of curved support members119(a) and119(b) thereafter. Specifically, the first curved support member119(a) is connected to the back supporting leg114(a) at a joint A and the front supporting leg112(a) at joint B. Similarly, the second curved support member119(b) is connected to the back supporting leg114(b) at a joint and the front supporting leg112(b) at joint B as illustrated inFIG. 2. Any suitable means may be employed to connect the front supporting legs112(a) and112(b), and the back supporting legs114(a) and114(b) to the curved support members119(a) and119(b). Preferred embodiments can include welding, soldering or brazing at the joints A, A, B and B.
• Referring specifically toFIG. 2, two horizontal support members118(a) and118(b) are connected at one of their ends to the curved support members119(a) and119(b) respectively. Specifically, one end of the first horizontal support member118(a) is connected (preferably welded) to the first curved support member119(a) and thus connected to theframe110. Similarly one end of the second horizontal support member118(b) is connected to the second curved support member119(b) and hence connected to theframe110. The curved support members119(a) and119(b) are equal in length and have identical geometrical structure and dimensions. Not limiting the scope, the horizontal support members118(a) and118(b) may also be connected to any other suitable location on theframe110 instead of being connected to the curved support members119(a) and119(b). A major fraction of the length of the horizontal support members118(a) and118(b) hangs in the air and acts as a base for mounting thehorizontal member130.
• Referring toFIG. 3, theupright member120 is mountable over the curved support members119(a) and119(b).
• Aplank122 is provided at the base of theframe110, and is disposed between the back supporting legs114(a) and114(b). Thebase edge123 of theupright member120 rests over the top of theplank122 and the edges of theupright member120 fit into a set of rectilinear slots provided inside the curved support members119(a) and119(b). More specifically, aslot127 is provided at the plank's top surface, extending to a specific depth within theplank122, and thebase edge123 of theupright member120 is inserted within theslot127 when theupright member120 is mounted over theframe110. Similarly, slots are engraved within inner surfaces of the curved support members119(a) &119(b) and the side edges124 and125 of theupright member120 remain respectively inserted within the slots in these curved support members119(a) and119(b) when theupright member120 is in a mounted position over theframe110.
• In the assembled state of theshielding module100, theupright member120 extends to the tip of the curved support members119(a) and119(b), though it can also extend further in certain embodiments. Thehorizontal member130 is carried partially beneath theupright member120 and extends further beyond it in the mounted position over theframe110.
• FIG. 4 depicts acomplete shielding module100, including anupright member120 and an associatedhorizontal member130
• Theupright member120 stands generally erect, curving inward toward the field. This curvilinear shape thus has a concave surface121(a) and a convex surface121(b). The concave surface121(a) of theupright member120 faces the field and the convex surface121(b) faces impinging airflows. As shown, the curvature of this member is generally uniform; other embodiments may be formed in a variety of curvilinear profiles, suited to particular situations. For example, a given field may require anupright member120 having at least its lower portion approaching the vertical before curving inward. Other embodiments could require the upper portion of the upright member to curve sharply inwards toward the horizontal. Those of skill in the art will understand the principles set out in this disclosure to design an upright member meeting local requirements.
• Upright member120 can be formed from any suitable material, taking into account requirements of rigidity and stability, as adapted to the circumstances of the field where the shielding system will be installed. A significant proportion of design criteria for the upright member will depend on the nature of the field. In a large sports stadium, for example, the upright members could be formed of concrete, integral with or attached to the stadium walls. Other installations might require a lighter material, while other installations could be made on a temporary basis. Such constructional details are well within the level of skill in the art.
• Theupright member120 has associated with it ahorizontal member130, the latter member being generally planar and rectangular in form. Here, the function of this element, as set out below, allows for considerable divergence from flatness if desired. It will be understood that a curved element, while not ruled out by design considerations, will most likely not perform as well as a generally planar one. As shown,horizontal member130 is mounted at the lower end of its associatedupright member120. In some embodiments, thehorizontal member130 may be attached directly to theupright member120. The implementation described above, however, employing an indirect method, as described in connection withFIG. 3. The point on theupright member120 at which the two members meet is chosen based on design criteria present at the field where given shieldingmodules100 are installed. Those of skill in the art will understand the process of selecting an appropriate design.
• The orientation of thehorizontal member130 lies generally parallel to the surface of the field. Some variation is possible in certain embodiments, at a price of reduced performance. The volume defined by the overlap of theupper member120 andhorizontal member130 is a critical performance factor, as explained below. With an increase in inclination ofhorizontal member130 above the horizontal, that volume would decrease, impairing the collaborative functionality of theupright member120 and thehorizontal member130. Therefore, inclination of thehorizontal member130 either above or below the defined horizontal level should not preferably vary beyond a range of 0 to 30 degrees for being functionally effective, the preferred orientation being generally parallel to the defined horizontal level.
• The extension of thehorizontal member130 beyond theupright member130 and hence its projection towards the field is a variable aspect dependent on parameters including the field size. For an implementation over a playing field, the extent of the spectators' seating area should also be considered. With appropriate design consideration,horizontal member130 can extend to also serve as a sunshade for at least some spectators during daylight hours.
• Two supporting wires140 (shown inFIG. 2) provide further support for thehorizontal member130 by connecting it to the curved support members119(a) and119(b) of theframe110. The supportingwires140 reduce the gravitational effects on the orientation of thehorizontal member130 by sharing the load on the horizontal support members118(a) and118(b).
• FIG. 4 also depictstrap zone400, defined as spaced enclosed within the overlap between theupright member120 and thehorizontal member130. The functionally active region oftrap zone400 extends primarily between the volume between the concave surface121 (a) of theupright member120 and the portion of theupper surface132 of thehorizontal member130 lying beneath theupright member120. Thevirtual walls402 illustrate this region. Operation of thetrap zone400 is described in some detail below.
• Whatever mounting method is chosen for fixing thehorizontal member130 in place, that process must substantially close any gap between the two members. A complete seal is not required, but any airflow between the members must be sufficiently low to allow the build up and maintenance of elevated pressure within thetrap zone400. Thus, the assembly method described in connection withFIG. 3 would suffice to accomplish that goal, as would other suitable construction methods known in the art.
• A portion of ashielding system500 of the present disclosure, installed at an outdoor sports venue, is seen inFIG. 5. There, threeindividual shielding modules100 are mounted in mutual abutment at a field (not shown). Mounting details can be left to the skill of those in the art, but the mutual abutment between adjacent shielding modules should prevent any substantial airflow between them. As shown, construction and mounting of thehorizontal members130 associated with eachupright member120 should cause adjacenthorizontal members130 to similarly abut, with no substantial airflow between them. Theshielding system500 shown inFIG. 5 is installed around the upper periphery of afield viewing area200. Such a mounting location is helpful, as the increased height of thefield viewing areas200 increases the effectiveness of theshielding system500, as will be seen. Where no some of your mounting platform is available, a special platform or fence could be erected to increase the effective height of thesystem500, or theupright members120 could be mounted directly at field level. Considerations of performance, cost, and vulnerability to damage from particularly high wind should be taken into account, as known to those in the art.
• FIGS. 6 and 7 depict acomplete shielding system500 mounted atop the periphery ofspectator viewing area200 surrounding a playing field600. Here, the field is asoccer stadium702, but in any sports, concert, or other cultural venue would benefit from the installation of an effective wind shield system. As shown,shielding system500 extends completely around the upper periphery of thestadium702, withindividual shielding modules100 in mutual abutment. No substantial gaps should exist between adjacentupright members120 orhorizontal members130.
• Theshielding system500 shown inFIG. 7 extends completely around thestadium702, but cost or other considerations could preclude the installation of a complete system. In that event, apartial shielding system500 could be installed, withsufficient shielding modules100 mounted in mutual abutment to block some of the impinging wind. Those of skill in the art will understand that appropriate positioning of the shieldingmodules100 can be accomplished employing protocols used to select airport runway orientations in alignment with prevailing wind conditions. For best performance, as explained below, thepartial shielding system500 should be divided into paired sets of shieldingmodules100. Once a prevailing wind direction has been identified and selected for coverage,partial shielding systems500 should be installed at the upwind and downwind sides of the field to maximize the wind blocking that can be achieved.
• Operation of theshielding system500 of the present disclosure is diagrammatically set out inFIG. 8. As shown there, ashielding system800 is mounted at afield802, extending around the upper periphery ofstadium804. An impingingairstream806 flows in the direction of arrow A, which may be in the same direction as the prevailing wind in that location. The system is divided into anupwind shielding system800aand adownwind shielding system800b. It should be noted that the shielding system may be installed as shown inFIG. 8, in which case the upwind and downwind systems,800aand800b, are defined by the wind direction (arrow A), and those designations change as the wind direction shifts. Other embodiments could employ partial shielding systems, as discussed above. Such embodiments would include separate upwind and downwind systems.
• As shown,airstream806, encounters theupwind shielding system800a, where it strikes theconvex surface821 ofupright members820. That surface deflectsairstream806 upwards, and due to the ‘Coanda Effect,’airstream806 tends to adhere to theconvex surface821. As a result, the airflow is not simply deflected upward, but rather it tends to follow the contour of theupwind shielding system800a, emerging from the upper end of that structure asairstream807 having an altitude higher than that of the impingingairstream806, with a velocity component generally horizontal, parallel to the field surface (not shown). The liftedairstream807 tends to remain substantially parallel to the field
• When theairstream807 crosses the field, it encounters theopen trap zones400 of thedownwind shielding system800b. The upper layers of theairstream807 flow over the system, but the lower layers ofairstream807 flow into the closed ends oftrap zones400. Theoncoming airstream807 exerts pressure on the air already in thetrap zones400, compressing it. After a short time, regions of substantially high pressure are created in and around thetrap zones400. These high pressure regions then deflectairstream807 upward, away from the field. These high pressure regions line within and in front ofdownwind shielding system800bact as barriers, preventingairstream807 from reaching the field. Consequently, the field is protected from the oncoming wind.
• Identical analysis applies to the case in which an entire shielding system extends around the upper periphery of a stadium. There, the upwind shielding system is simply that portion of the shielding system located on the side of the stadium from which the wind is blowing, and the downwind shielding system is simply that portion of the shielding system located on the opposite side of the stadium. The various wind flows resulting from the oncoming airstream encountering the convex surface of the upwind shielding system, followed by the cross-field airflow encountering the high pressure region surrounding thetrap zones400 are identical to that described above.
• The shielding system of the present disclosure offers the possibility of significantly reducing wind effects on a playing field, a concert performance, or any other cultural event. Thus, players can perform at their utmost, singers, actors, and audience can enjoy a show, and cultural events can proceed without interruption. These and other advantages are possible with the employment of the shielding system disclosed here. Specific embodiments, as well as alternatives and variations have been described here in considerable detail. Those in the art will understand that still other variations will occur to those in the art, all line within the scope of the present disclosure.

Claims (20)

1. A shielding system for a field, the shielding system comprising:

a plurality of upright members, mounted in mutual abutment adjacent to the field, each upright member being curvilinear in form and having a distal end projecting upwardly from and inwardly toward the field; and

a horizontal member associated with each upright member, the horizontal member being mounted at the lower end of the associated upright member and projecting inwardly toward the field.

2. The shielding system ofclaim 1, wherein connections between the upright members and the horizontal members are configured for blocking airflow therebetween.

3. The shielding system ofclaim 1, wherein the upright members project at least partially over the horizontal members, defining a trap zone therebetween.

4. The shielding system ofclaim 1, the shielding system being subjected to an impinging airflow, wherein the shielding system extends at least partially around the field, defining at least an upwind portion and a downwind portion.

5. The shielding system ofclaim 3, wherein the shielding system presents a convex surface at the upwind side of an impinging airflow and presents the trap zones at the downwind side of an impinging airflow.

6. The shielding system ofclaim 1, wherein the convex surfaces of abutting upright members are configured to raise the altitude of and impart a substantial horizontal flow component to an impinging airflow.

7. The shielding system ofclaim 1, wherein the upright members project at least partially over the horizontal members, defining a trap zone therebetween, the trap zone being configured to produce a zone of relatively higher pressure therein when subjected to an airflow into the trap zone.

8. The shielding system ofclaim 5, wherein the shielding system extends around the field to block at least the upwind and downwind portions of the field, and wherein the upwind portion of the shielding system is configured to respond to the impinging airflow by raising the altitude of and imparting a substantial horizontal flow component to the airflow, and wherein the downwind side of the shielding system is configured to respond to the impinging airflow by producing a zone of high pressure in the trap zone of the downwind side of the shielding system for at least partially deflecting the airflow upward from the field.

9. A shielding system for a field subjected to impinging airflows, the shielding system comprising:

a plurality of upright members, mounted in mutual abutment adjacent to the field, each upright member being curvilinear in form and having a distal end projecting upwardly from and inwardly toward the field, having a horizontal member associated with each upright member, the horizontal member being mounted at the lower end of the associated upright member and projecting inwardly toward the field, the upright members projecting at least partially over the horizontal members, defining a trap zone therebetween;

the shielding system extending around the field sufficient to block at least the upwind and downwind portions of the field, wherein the upwind portion of the shielding system is configured to respond to the impinging airflow by raising the altitude of and imparting a substantial horizontal flow component to the airflow, and wherein the downwind portion of the shielding system is configured to respond to the impinging airflow by producing a zone of high pressure in the trap zone of the downwind portion of the shielding system for at least partially deflecting the airflow upward from the field.

10. A shielding module for a field, the shielding module comprising:

an upright member, mounted adjacent to the field, the upright member being curvilinear in form and projecting inwardly toward the field; and

a horizontal member associated with the upright member, the horizontal member being mounted at the lower end of the associated upright member and projecting inwardly toward the field.

11. The shielding module ofclaim 10, wherein the upright member and the horizontal member are generally connected to define a closed end.

12. The shielding module ofclaim 10, wherein the horizontal member lies at least partially beneath the upright member.

13. The shielding module ofclaim 10, wherein the upright member has a convex surface facing outwardly from the field.

14. The shielding module ofclaim 10, the upright member having a variable radius of curvature.

15. The shielding module ofclaim 10, wherein the horizontal member is substantially flat.

16. The shielding module ofclaim 10, wherein the horizontal member lies substantially parallel to the field surface.

17. The shielding module ofclaim 1, wherein the horizontal member is inclined above or below a horizontal level.

18. A shielding module ofclaim 10, wherein the convex surface of the upright member redirects an impinging airflow along the curved surface of the upright member to raise the airstream altitude.

19. The shielding module ofclaim 10, wherein the upright member and the horizontal member define a trap zone located therebetween, for deflecting an impinging airstream.

20. The shielding module ofclaim 10, wherein the field is any area for conducting an event.

Images