Abstract:
A wave generating system comprising: a semi-submerged water displacement hull adapted to travel along a travel path within a wave pool, thereby generating a wake; and a wake modulator adapted to modulate the wake; wherein at least one of the travel path of the hull relative to the wake modulator and the travel of the wave modulator relative to the wake generated by the hull is controlled to effect the modulation of the wake.

Description:
FIELD OF INVENTION 
       [0001]    The present invention relates to wave generating systems. The invention particularly relates to wave generating systems that facilitate modulation of a wake generated by the system. 
       SUMMARY OF INVENTION 
       [0002]    According to one aspect of the invention there is provided a wave generating system comprising:
       a semi-submerged water displacement hull adapted to travel along a travel path within a wave pool, thereby generating a wake; and   a wake modulator adapted to modulate the wake;   wherein at least one of the travel path of the hull relative to the wake modulator and the travel of the wave modulator relative to the wake generated by the hull is controlled to effect the modulation of the wake.       
 
         [0006]    In one embodiment, the wake modulator comprises contours of a floor of the wave pool and wherein the travel path of the hull is non-parallel with the contours. The travel path of the hull may be at a predetermined angle relative to the contours, or may follow a meandering path relative to the contours. 
         [0007]    In certain embodiments, the hull comprises a panel extending from the stern of the hull. In other embodiments, the hull is rotatably mounted relative to a carriage. 
         [0008]    In another embodiment, the wake modulator comprises at least another hull adapted to travel along a travel path within the wave pool, thereby generating another wake, and wherein modulation of the wake comprises an interaction between the wake and the other wake. 
         [0009]    The travel paths of the hulls may be substantially identical, and the hulls disposed at a distance from one another such that wakes generated by a prior hull are superimposed by wakes of a following hull. 
         [0010]    The travel paths of the hull and the other hull may alternatively be towards one another such that the wake and the other wake intersect to form a bulge that advanced laterally across the wave pool. 
         [0011]    The travel paths of the hull and the other hull may alternatively be in the same direction on opposing sides of the wave pool such that the wake and the other wake intersect to form a concave wave front disposed between the travel paths. 
         [0012]    In a further embodiment, the wake modulator comprises a submerged foil adapted to travel along a travel path parallel to the travel path of the hull and at a predetermined distance preceding the wake generated by the hull such that the foil forms a trough that modulates the wake. 
         [0013]    In yet another embodiment, the wake modulator comprises a submerged reef adapted to travel along a travel path parallel to the travel path of the hull and at a predetermined distance behind the hull such that the wake generated by the hull travel over the reef as the reef advances, thereby causing the wake to break over the reef. 
         [0014]    The submerged reef may comprise an adjustable panel that can be adjusted relative to the wake of the hull. 
         [0015]    Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated step or element or integer or group of steps or elements or integers, but not the exclusion of any other step or element or integer or group of steps, elements or integers. Thus, in the context of this specification, the term “comprising” is used in an inclusive sense and thus should be understood as meaning “including principally, but not necessarily solely”. 
         [0016]    The present invention consists of features and a combination of parts hereinafter fully described and illustrated in the accompanying drawings, it being understood that various changes in the details may be made without departing from the scope of the invention or sacrificing any of the advantages of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS 
         [0017]    To further clarify various aspects of some embodiments of the present invention, a more particular description of the invention will be rendered by references to specific embodiments thereof, which are illustrated in the appended drawings. It should be appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting on its scope. The invention will be described and explained with additional specificity and detail through the accompanying drawings in which: 
           [0018]      FIG. 1  illustrates a hull moving along a travel path that is parallel to contours of a wave pool. 
           [0019]      FIG. 2  illustrates a hull moving along a travel path that is not parallel to contours of a wave pool. 
           [0020]      FIG. 3  illustrates a hull moving along a meandering travel path relative to contours of a wave pool. 
           [0021]      FIG. 4  illustrates a hull moving along a travel path that is not parallel to contours of a wave pool, generating a deflective wake. 
           [0022]      FIG. 5  illustrates a hull provided with a panel extending from the stern thereof. 
           [0023]      FIG. 6  illustrates a hull moving rotatably mounted on a carriage as it moves along a travel path that is not parallel to contours of a wave pool. 
           [0024]      FIG. 7  illustrates two hulls moving along a travel path that is parallel to contours of a wave pool. 
           [0025]      FIG. 8  illustrates a first hull moving along a travel path that is parallel to contours of a wave pool. 
           [0026]      FIG. 9  illustrates two hulls moving along a travel path that is parallel to contours of a wave pool. 
           [0027]      FIG. 10  illustrates two hulls moving along opposing travel paths. 
           [0028]      FIG. 11  illustrates the two hulls of  FIG. 10  at the end of their travel paths. 
           [0029]      FIG. 12  illustrates two hulls moving along travel paths on opposing sides of a wave pool. 
           [0030]      FIG. 13  illustrates a hull moving along a travel path that is parallel to a travel path of a preceding submerged foil. 
           [0031]      FIG. 14  illustrates a cross sectional view of the system of  FIG. 13 . 
           [0032]      FIG. 15  illustrates a hull moving along a travel path that is parallel to the travel path of a following reef. 
           [0033]      FIG. 16  illustrates a cross sectional view of the system of  FIG. 15 . 
           [0034]      FIG. 17  illustrates a hull moving along a travel path that is parallel to the travel path of a following reef. 
           [0035]      FIGS. 18-20  illustrate cross sectional views of the system of  FIG. 17 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0036]    Hereinafter, this specification will describe the present invention according to the preferred embodiments. It is to be understood that limiting the description to the preferred embodiments of the invention is merely to facilitate discussion of the present invention and it is envisioned without departing from the scope of the appended claims. 
         [0037]    The present invention relates to recreational wave pools. The purpose of this invention is to change wave shape to suit various aspects of surfing performance. 
         [0038]    To efficiently transform wave shape, the present invention provides for at least one of the following:
       1. Manipulates swell size, speed and direction, by controlling the position of a semi-submerged water displacement member (hereafter the “hull”) relative to the contours of the pool floor;   2. Produces overlapping wakes, by controlling the relative position, speed and configuration of multiple hulls;   3. Manipulates water level, by controlling the position of a submerged water displacement member (hereafter: the “foil”) relative to an advancing wake; and   4. Manipulates surf zone bathymetry, by controlling the position of a wave obstruction member (hereafter: the “reef”) relative to the water surface.       
 
         [0043]      FIG. 1  depicts a system  100  in which a hull  105  moving along a travel path  110  proximate the edge of a pool  115 , in a direction that is parallel to the contours  120  of the pool floor, such that the resulting wake  125  advances at a constant angle, depicted here as 45 degrees to the contours  120 , upon which the wake is designed to break.  FIG. 2  depicts a similar system  200  having the same elements as  FIG. 1 , except that the travel path  210  of the hull  205  is now five degrees off parallel to the contours  220  of the pool floor, resulting in a five degree reduction in the angle of its wake  225 , which now advances at an angle of 40 degrees, instead of 45 degrees, as depicted in  FIG. 1 . The angle of the travel path  210  of the hull  205  may advantageously be modified to modulate the angle of the wake  225  relative to the contours  220  of the pool floor. 
         [0044]      FIG. 3  depicts an alternative system  300  having the same elements as  FIG. 2 , except that the hull  305  now follows a meandering path  310 , resulting in the angle of its wake  325  changing in response to the various directions followed by the hull  305 . Apart from producing waves that continually change shape, the meandering path  310  increases wave power by compressing the wave front each time it turns toward the side that releases the wake  325 . 
         [0045]    Referring to  FIGS. 4 and 5 , a vertical panel  430  is suspended longitudinally from one side of the hull  405 , to prevent a wake  425 ′ from forming on that side of the hull  405 , when its path takes it away from the pool wall  415 , which would otherwise prevent the desired wake  425  from forming.  FIG. 4  depicts the undesirable occurrence of the wake  425 ′ bouncing off the wall  415  of the pool.  FIG. 5  depicts the hull  405  with a vertical panel  430  suspended from one side and extending beyond the stern of the vessel. 
         [0046]    In another, as depicted in  FIG. 6 , the hull  605  is supported by a carriage  635 , which allows it to pivot on the horizontal plane, so it can be aligned with the direction of its movement through the water along the travel path  610 .  FIG. 6  depicts the relationship between the alignment of the hull  605 , the travel path  610  it follows and the carriage  635  supporting it. 
         [0047]    The systems of  FIGS. 2-6 , described above, may further provide for altering the depth of the hull while it is being driven along the travel path such that the magnitude of its wake increases or decreases accordingly. Similarly, the systems may provide for alteration of the width of the hull while it is being driven along the travel path such that the magnitude of its wake increases or decreases accordingly. In other embodiments the systems may provide for increasing or decreasing the speed of the hull, such that the magnitude of its wake increases or decreases accordingly. A plurality of hulls may also be driven along the travel path on side of a channel, with successive hulls moving at different speeds, such that their wakes vary in size and speed. 
         [0048]    In certain embodiments of the present invention, a plurality of hulls is driven in close succession along the side of a channel, such that key differences in their size, draft and trim angle result in variously angled wakes, which subsequently intersect to produce favourable effects on the resulting wave.  FIG. 7  depicts two hulls  705 , which are traveling along the same path, but are producing differently angled wakes  725 , which subsequently intersect as they enter shallow water. 
         [0049]    As depicted in  FIGS. 8 and 9 , the plurality of hulls  805 ,  805 ′ are advantageously driven along the wall of a pool  815  with the hulls  805 ,  805 ′ spaced precisely one wavelength apart, such that the second wake  825 ′ from the preceding hull  805  merges with the first wake  825 ″ of the following hull  805 ′.  FIG. 8  depicts a single hull  805  producing a train of two wakes  825  and  825 ′.  FIG. 9  depicts two hulls  805 ,  805 ′ advancing along the same path, with each hull  805 ,  805 ′ producing a train of two wakes, such that the first wake  825 ″ of the trailing hull  805 ′ becomes aligned with the second wake  825 ′ of the preceding hull  805 . By overlapping the wake trains of multiple hulls, the wave size relative to energy input may be increased, while simultaneously maximising their rate of production, since the wave length of the preceding hull&#39;s wake determines how close the next hull can trail, without its wake unduly distorting the preceding hull&#39;s wake. 
         [0050]    In certain embodiments, the speed of the hulls may be controlled by a programmable logic computer, such that the distance between successive wave generating bodies maintains the correlation with wave length, as the resulting waves build in size and their wave lengths increase. 
         [0051]    In other embodiments, as depicted in  FIGS. 10 and 11 , two hulls  1005 ,  1005 ′ are driven toward each other, along one side  1015  of a channel, such that their wakes  1025 ,  1025 ′ intersect to form a bulge  1040 , which advances laterally across the pool, directly toward the shallows, where it forms into a peak, as it breaks. 
         [0052]    In another embodiment, as depicted in  FIG. 12 , two hulls  1205 ,  1205 ′ are driven along opposing sides  1215 ,  1215 ′ of a channel, in the same direction, such that their wakes  1225 ,  1225 ′ intersect in the middle of the channel, where they converge to form a concave wave  1240  front that advances along the centre line of the channel for as long as said wakes  1225 ,  1225 ′ continue to intersect. 
         [0053]    In a further embodiment, as depicted in  FIGS. 13 and 14 , a submerged foil  1350  is driven along a horizontal path  1355 , in front of a wake  1325  such that its effect upon the surface contours of the water converge with the wake  1325 . The method of propulsion could be self-contained, as with a submarine, or via a track fixed to the pool floor.  FIG. 14  depicts a cross-section A-B of the submerged foil  1350 , followed by a trough  1360 , which affects the wake  1325 , by increasing the depth of its trough  1365  and the height of its crest  1370 . 
         [0054]    In another embodiment, as depicted in  FIGS. 15 and 16 , a hull  1505  produces a wake  1525 , which forms into a breaking wave  1525 ′ as it crosses over a reef  1550  driven along a parallel path  1575 . The wake  1525  intersects the path  1575  of a reef  1550 , for example moving along a track, maintaining its position below the advancing wake  1525 .  FIG. 16  depicts the cross-section A-B, identified in  FIG. 15 , showing the reef  1550 , causing the wake  1525  to break in a manner determined by the shape and proximity of the reef  1550 . 
         [0055]    In an alternative embodiment, a hull produces a wake, which forms into a breaking wave as it crosses over a reef in the form of a submerged panel, which is driven along a path that is parallel to the path followed by said hull.  FIG. 17  depicts this arrangement, viewed from above, in which a hull  1705  produces a wake  1725  that intersects the path of a submerged panel  1750 , which maintains its position below the advancing wake  1725 , by moving along rails  1780  fixed to the pool floor. To minimise drag, the position of the submerged panel  1750  is flat with respect to its direction of movement. In cross-section, the submerged panel  1750  is curved, with its convex surface facing upward. The submerged panel  1750  is secured to a carriage  1785  by struts, which are independently extendable, to allow for the submerged panel  1750  to be repositioned relative to the surface.  FIG. 18  depicts the cross-section A-B, identified in  FIG. 17 , showing the submerged panel  150 , causing the wave to break  1725 ′ in a manner determined by the shape and proximity of the panel  1750 .  FIGS. 19 and 20  depict the same cross-section, now showing how the submerged panel  1750  can be repositioned at different depths and different angles, to change the shape of the wave  1725 ′ breaking above it. In  FIG. 19 , the submerged panel  1750  has been rotated 10 degrees to steepen the incline, which causes the wave  1725 ′ to break more abruptly, increasing its height and the breadth of its plunge.  FIG. 20  depicts the submerged panel  1750  raised as a unit to make the water shallower, so the wave  1725 ′ breaks even more abruptly, creating an even rounder concave in the cross-sectional profile of the plunging wave  1725 ′. 
         [0056]    Unless the context requires otherwise or specifically stated to the contrary, integers, steps or elements of the invention recited herein as singular integers, steps or elements clearly encompass both singular and plural forms of the recited integers, steps or elements. 
         [0057]    It will be appreciated that the foregoing description has been given by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons of skill in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.