CROSS-REFERENCE TO RELATED APPLICATIONS Not Applicable
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT Not Applicable
SEQUENCE LISTING, TABLE, OR COMPUTER PROGRAM Not applicable
BACKGROUND OF THE INVENTION Water theme parks have become increasingly popular in recent years. Water theme parks generally feature water-based rides and often provide other water-related activities. An attraction that has become popular at many water theme parks is the wave pool. Wave pools are typically man-made bodies of water wherein a wave generator is located at one end of the pool, and a sand beach is located at the other end. A typical wave pool is shown in FIG. 1. As illustrated in FIG. 1, waves created by the wave generator 120 travel across the water-filled pool 130 and break onto the beach area 110. In particular, attempts have been made to create non-breaking waves and spilling, breaking waves using mechanical wave generators that are designed to push large amounts of water back and forth in the pool. This movement is created on the deep end of the pool and involves creating waves that travel toward the opposite, more shallow end where the waves break. These wave generators are often driven by mechanical, pneumatic, or hydraulic means.
While many different methods have been attempted, one of the shortcomings of conventional wave pools is that swimmers may encounter a hazard at the end of the pool where the mechanical, pneumatic, or hydraulic wave-generating means is located.
As illustrated in FIG. 1, conventional wave pools also typically only have a narrow sloped beach area 110 upon which the waves will break. In such case, people who want to perform water skimming maneuvers in the shallow area near the beach often have to share the same space with those who simply want to wade, such as children and the elderly, which can disadvantageously increase the risk of accident and create an overcrowded situation in the beach area and within the pool.
Many water park participants enjoy recreational activities, such as sunbathing, picnicking, and volleyball, on the sand beach. Parents of young children often monitor their children from the beach area as they play in the pool. With a conventional wave pool, only a small portion of the pool perimeter can be used as beach area because the wave generation apparatus is situated at the deep end of the pool, with the beach area situated at the opposite, shallow end of the pool. Consequently, the beach may become overcrowded without the pool itself reaching capacity, forcing the theme park management to limit park admission, thereby reducing park revenue. Therefore, it would be advantageous to develop a wave pool with increased beach area.
Conventional wave pools typically create waves by moving water back and forth, and consequently, can only generate one wave at a time. In other words, only a single periodic wave can be created at any given moment in time, and time must pass between successive waves. While different sized and shaped pools and beaches can be provided, and the frequency of wave generation can be changed, only one wave can be created at a particular time. In such circumstances, particularly when wave pools are crowded, there is often little space or opportunity for participants to ride the waves. Either the occupancy of the pool must be limited or larger pools with additional wave generating capacity must be provided in order for more people to enjoy the waves.
In addition to overcrowding, creating waves one at a time by moving water back and forth means most of the energy used to generate a wave's forward momentum is lost as the wave traverses the pool toward the beach. Generating a sequence of waves requires repeatedly generating forward momentum for each wave generated. Because water has a high density (i.e., it is relatively heavy per unit volume compared to, say, air), the repeated generation of forward momentum consumes a substantial amount of energy.
In view of the limitations of existing wave pools outlined above, the invention described herein is concerned with a wave pool capable of safely and efficiently generating one continuous wave or multiple simultaneous continuous waves in a wave pool, and increasing the available beach area, so that participants with different interests can co-exist and play at the same time in the same pool. Recreational wave pools are well known in the art. Many methods of generating waves in recreational wave pools are known. Conventional wave pools generate waves on one side of a wave pool. These waves travel across the pool to the other sides of the wave pool. However, by generating waves from a central island of a wave pool, rather than from an edge of the pool, many benefits can be realized. For example, the useable beach area bounding the wave pool can be increased in size because the edge of the pool is not being used for wave generation. Further, a more efficient wave generation apparatus can be employed because wave generation is more localized. Finally, wave generation from a central island has numerous added safety benefits. Therefore, it would be advantageous to construct a wave pool with a central island for wave generation.
BRIEF SUMMARY OF THE INVENTION The present invention relates generally to a wave forming apparatus and is partially concerned with water rides of the type provided in water-based amusement parks, particularly a wave-forming apparatus and method for forming waves in a pool.
According to one aspect of the present invention, a wave generating apparatus is provided on a central island within a swimming pool filled with water. The central island may be shaped in various ways, but the preferred shape is substantially round. The wave pool itself may take various shapes but it is preferred that it is substantially round. Various methods of generating waves in the pool may be provided on the central island. In one preferred embodiment, one or more caissons are provided on the central island to generate waves in the pool. In another preferred embodiment, a wave generator is provided on the central island, the wave generator comprising a wave-generating shaped surface (or plow), a channel, and a reef. The channel and reef form a ring about the outer perimeter of the central island. The plow is connected via an armature to a motor on the central island. The motor rotates, drawing the plow through the ring-shaped channel, displacing water from the channel over the reef and into the pool, forming a wave in the pool.
In some embodiments, a portion of the central island preferably extends above the pool's static water line and out of the water to keep the motor above water and thus dry. In other embodiments, a waterproof wall is formed on the central island, blocking the pool's water from reaching the motor while concealing the motor from view.
In some embodiments, the floor of the channel is positioned below the pool's static water line. The reef bounds the channel's outer perimeter. The top of the reef is positioned above the channel floor. The top of the reef may be positioned at any height above the channel floor, but preferably is positioned at a height that allows gravity to refill the channel with water from the pool without degrading the wave-enhancing effect produced by the reef. A pool area suitable for swimming and other water recreation activities bounds the reef. A beach recreation area bounds the outer perimeter of the wave pool.
In one embodiment of the invention, a rotating armature with a motor to rotate the armature is positioned on the central island. A wave-generating shaped surface (i.e., a plow) is attached to the armature and extends below the static water line into the water-filled channel. Rotation of the armature causes the plow to rotate in the channel about the central island. The plow's motion through the channel displaces water from within the channel over the top of the reef and into the pool area. The volume of the displaced water, and its inertia, forms a wave in the pool that travels outward from the central island toward the pool perimeter and beach.
In some embodiments, the island wave pool comprises a pool having a shallow pool area surrounding a deeper central pool area, a beach area bounding the pool, a central island located within the central pool area, a ringed channel on the central island bounded by a reef, at least one armature having a wave-generating shaped surface (i.e., a plow) within the channel and moveable therein to generate a wave in water in the pool.
The plow can also be of any shape suitable to generate a wave when drawn through the water, and is preferably substantially flat in shape.
It is preferred that the apparatus also includes drive means located on the central island, rotating at least one wave-generating plow in the channel. The drive means can take various forms, and is preferably a pneumatic motor.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING A more complete understanding of the subject matter may be derived by referring to the detailed description and claims when considered in conjunction with the following figures, wherein like reference numbers refer to similar elements throughout the figures.
FIG. 1 is a schematic illustration, in top view, of a conventional wave pool found in the prior art;
FIG. 2 is a schematic illustration, in top view, of one embodiment of an island wave pool;
FIG. 3 illustrates schematically, in cross section, one embodiment of an island wave pool;
FIG. 4A is a schematic illustration, in cross section, of one embodiment of a stepped transition between the pool and beach areas at the pool perimeter;
FIG. 4B is a schematic illustration, in cross section, of one embodiment of a sloped transition between the pool and beach areas at the pool perimeter;
FIG. 5A illustrates schematically, in cross section, one embodiment of one side of an island wave pool comprising a water-filled caisson wave generator on a central island within the pool;
FIG. 5B illustrates schematically, in cross section, one embodiment of one side of an island wave pool and the operation of a water-filled caisson wave generator on a central island within the pool;
FIG. 6 illustrates schematically, in top view, one embodiment of a central island wave generator comprising four water-filled caissons;
FIG. 7 schematically illustrates, in cross section, one embodiment of a central island wave generator comprising a plow, channel, and reef;
FIG. 8 is a schematic illustration, in top view, of one embodiment of a central island wave generator comprising a plow, channel, and reef;
FIG. 9 is a schematic illustration, in cross section, of one embodiment of a drive system of a plow, channel, and reef wave generator on a central island;
FIG. 10A illustrates schematically, in cross section, one embodiment of one side of an island wave pool comprising a gutter;
FIG. 10B illustrates schematically, in top view, one embodiment of an island wave pool comprising a gutter;
FIG. 11 is a schematic illustration, in cross section, of one embodiment of a plow, channel, and reef wave generator on a central island comprising an adjustable vertical plow angle;
FIG. 12 is a schematic illustration, in top view, of one embodiment of a plow, channel, and reef wave generator on a central island comprising an adjustable radial plow angle;
FIGS. 13A & 13B are schematic illustrations, in perspective view, of two embodiments of different plow shapes;
FIG. 14 illustrates schematically, in top view, one embodiment of a plow, channel, and reef wave generator on a central island, wherein the wave generator comprises multiple plows with equal angular distribution about the axis of rotation;
FIG. 15 is a schematic illustration, in top view, of one embodiment of a plow, channel, and reef wave generator on a central island, wherein the wave generator comprises multiple plows with balanced angular distribution about the axis of rotation;
FIG. 16 schematically illustrates, in cross section, one embodiment of a central island of an island wave pool, the central island comprising a shark cage and lifeguard towers positioned above the outer perimeter of the central island; and
FIG. 17 schematically illustrates, in top view, one embodiment of a central island of an island wave pool, the central island comprising a shark cage and lifeguard towers positioned above the outer perimeter of the central island
DETAILED DESCRIPTION OF THE INVENTION The following detailed description is merely illustrative in nature and is not intended to limit the embodiments of the invention or the application and uses of such embodiments. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary or the following
I. Definitions
An island wave pool has a pool containing water for recreational activities. As swimmers in the pool of water swim and play, their movement disturbs the water, causing relatively small waves to traverse the pool surface. An operating wave generator in the pool causes relatively large waves to traverse the pool surface. Consequently, at a given point on the surface of a pool having swimmers or an operating wave generator, the surface level rises and falls over time as waves intersect the given point. In contrast, when there are no swimmers in the pool, the air is still, and the wave generator is idle, the body of water in the pool is at rest, the surface is flat, and the surface level is constant. As used herein, the term “static water line” refers to the average surface level of the water in an island wave pool. The static water line of an island wave pool is equivalent to the surface level of the pool when the body of water in the pool is at rest (e.g., there are no waves in the pool). When an island wave pools has waves, the wave peaks and troughs generally reach their extremes at points above and below the static water line, respectively. The static water line reflects the actual water level in a pool at a given time, independent of designed fluid capacity of the pool.
As used herein, the term “pool” will be used to encompass any receptacle, enclosure, excavation or the like adapted to contain a body of water. The term “wave” will be used to encompass breaking and non-breaking waves, as well as periodic and non-periodic transmissions of energy in a body of water.
As used herein, the term “depth” refers to the vertical underwater distance between a point on the floor of the pool and the static water line directly above the point.
II. General Wave Pool Characteristics
The island wave pool of some embodiments of the present invention is a recreational pool such as the type found at water amusement parks. To provide recreational waves for its users' enjoyment, the island wave pool is typically filled with water. When filled with water, users of the island wave pool may wade, swim, dive, ride waves, or engage in other recreational water activities in and about the pool. FIG. 2 illustrates the island wave pool 200 of some embodiments as viewed from above. FIG. 2 also shows the water-filled pool 230 and the pool perimeter 210. The pool 230 is a swimming area used for recreational water activities. As shown in FIG. 2, the preferred shape of the pool 230, as viewed from above, is substantially round. However, limitations on the land available for wave pool construction, such as the shape or grade of the land upon which the wave pool will be built, or obstacles such as prior construction or natural land features, will necessitate construction of a pool 230 in a shape other than round. Nonetheless, the pool 230 may take shapes other than round without departing from the spirit of the invention.
FIG. 2 illustrates the central island 220 of some embodiments. In some embodiments, central island 220 is positioned in a central location within pool 230. The central island 220 need not be positioned in the precise center of the pool 230, but should be positioned within the pool such that the entire perimeter of the central island 220 is bounded by water from the pool 230. In some embodiments, the central island is positioned in the center of the pool 230. In other embodiments, the central island 220 is positioned offset from the center of the pool 230, but no point on the central island 220 is located closer than five meters from the pool perimeter 210. In other embodiments, the central island 220 is positioned offset from center and at a distance from the pool perimeter 210 no less than ten percent of the pool's 230 smallest measured diameter. When viewed from above, central island 220 is preferably round in shape. As will be discussed in Section III, in some embodiments, waves in the pool 230 are generated from the central island 220.
In some embodiments, the pool 230 surrounds the central island 220 and extends outward in all directions to the pool perimeter 210. Waves generated on the central island 220 travel outward from the central island 220 through the pool 230 until they reach the pool perimeter 210. Users of the island wave pool 200 can use the pool 230 for wading, swimming, diving, wave riding, water sports, and other activities.
A. Beach Recreation Area
FIG. 2 illustrates the beach area 240 of some embodiments. The beach area 240 is a normally dry zone outside of the pool 230 bounding the pool perimeter 210. In some embodiments, the beach area 240 facilitates entry to and exit from the pool 230. The surface of the beach area 240 may be made from any type of material suitable for poolside beach-area flooring. In some embodiments, the beach area 240 is a sand beach. In other embodiments, the beach area 240 is a concrete beach. In yet other embodiments, beach area 240 is formed using a combination of sand and concrete beach areas. Other examples of suitable beach-area flooring include natural grass, artificial grass or turf, and rubber floor surfaces.
The beach area 240 of some embodiments is used for beach and poolside recreational activities. Examples of beach and poolside recreational activities include sunbathing, picnicking, relaxation, and sports such as volleyball, paddleball, and tossing catch. Other beach and poolside activities include monitoring children swimming and riding waves in the pool, reading, and drying off from being wet. Visitors to a wave pool often settle at temporary encampments in the beach area 240, where they may set out chairs or place towels down to rest and relax upon, and to keep their belongings while swimming and riding waves in the pool.
As illustrated in FIG. 3, in some embodiments, the slope of the beach floor 320 rises from the pool perimeter 210 outward in the direction away from the pool 230. When waves are formed in the pool 230, water may flow from the pool 230 onto the beach area 240. The rising slope of the beach floor 320 ensures that gravity drains the water entering the beach area 240 back into the pool 230.
Safety is of utmost concern in any water attraction. Therefore, while the beach floor 320 may be sloped upward to ensure proper drainage, the slope 420 illustrated in FIG. 4B formed by the beach floor 320 of some embodiments is gentle enough to facilitate ease of access and safety. For example, in some embodiments, the beach floor 320 is sloped in any direction at less than or equal to one vertical meter for each 20 horizontal meters of travel (a 1:20 ratio). In other embodiments, the beach floor slopes in any direction at less than or equal to one vertical meter for each fifty horizontal meters of travel (a 1:50 ratio). In some embodiments, a particular maximum slope ratio (e.g., 1:20, 1:50, etc.) is considered a safe slope ratio. In some embodiments, only a portion of the beach area 240 surrounding the pool perimeter 210 (e.g., one half or three quarters of the beach area surrounding the pool perimeter) forms a beach floor whose incline is at or below a specified safe slope angle.
As illustrated in FIG. 2, the beach area 240 of some embodiments is formed about the entire perimeter 210 of the pool 230. Forming beach area 240 about the entire pool 230 maximizes the size of the beach area 240 available for leisure and recreation. This maximized area, in turn, maximizes the capacity of people that may safely and comfortably occupy the beach area 240. This is important in an amusement park, where increased capacity gives rise to the potential for increased revenue and profit. In other embodiments, the beach area 240 substantially, but not completely, encloses the pool 230. In other embodiments, at least 50% of the pool perimeter 210 is bounded by beach area. In yet other embodiments, at least 75% of the pool perimeter 210 is bounded by beach area.
B. Wave Pool Water Recreation Area
FIG. 3 illustrates a cross sectional view of an island wave pool 200. An island wave pool may be constructed above ground, below ground, or partially above and partially below ground level. The example embodiment illustrated in FIG. 3 shows an island wave pool constructed below ground level. As illustrated in FIG. 3, the pool floor 310 holds the water within the pool 230. The materials used to construct pool floors, liners, and bottoms are well known in the art. Such materials are generally capable of containing water, withstanding water loading and pressure caused by the weight of the water contained, are tolerant of chemical additives used in swimming pools to maintain water quality (e.g., chlorine, bromine, acids, bases, etc.), and may feature an aesthetically pleasing color and/or texture. In some embodiments, the pool floor 310 is formed using any such material suitable for constructing a pool floor, liner, or bottom. For example, in some embodiments, the pool floor 310 is a concrete pool floor. In other embodiments, the pool floor 310 is a sand pool floor. Still other embodiments incorporate a plaster coating for pool floor 310. Other examples of pool bottom materials include fiberglass, epoxy resins, and a composite mixture of white Portland cement with smaller aggregate such as quartz, pebble or marble for strength and good looks. In some embodiments, pool floor 310 is constructed using a combination of such suitable pool bottom materials.
As shown in FIG. 3, in some embodiments, a shallow pool area 250 is formed in the pool 230 in the outer pool area adjacent to the pool perimeter 210. The shallow pool area 250 has a water depth shallow enough to allow a walking entry to (and exit from) the pool 230. A walking entry/exit area of a pool is a portion of a pool's perimeter where a swimmer can walk directly into (or out of) the pool (i.e., without diving or jumping in, or climbing out, respectively).
With conventional wave pools, if a walking entry/exit area is provided, it is generally placed on only one side of the wave pool, with the wave generation apparatus occupying the perimeter of the pool opposite the walking entry area. Safety requires that swimmers be separated from the mechanical wave generation apparatus, making a substantial portion of the wave pool's perimeter off limits to swimmers and spectators. Because the walking entry/exit area is the easiest and safest place to enter and exit the pool, it is the part of the pool where swimmers and observers prefer to rest and remain while they are not swimming.
As illustrated in FIG. 2, in some embodiments, the entire perimeter 210 of the pool 230 is bounded by a shallow pool area 250 facilitating walking entry and exit to and from the pool 230. By forming a shallow pool area about the entire circumference of the pool, the length of the pool perimeter useable for walking entry and exit is maximized. In some embodiments, not all of the pool perimeter is bounded by shallow water. For example, in some embodiments, at least 50% of the pool perimeter 210 is bounded by a shallow pool area (i.e., at least half of the pool 230 is bounded by shallow zones facilitating walking entry and exit). In yet other embodiments, at least 75% of the pool perimeter 210 is bounded by a shallow pool area facilitating walking entry and exit.
As illustrated in FIGS. 2, 3, 4A, & 4B, a transition occurs at the pool perimeter 210. This transition occurs between the beach floor 320 and the pool floor 310 at the shallow outer area of the pool 230. The transition illustrated in FIG. 3 is an example of a straight transition (i.e., no step, edge, or curve) at the pool perimeter 210 between the pool floor 310 and the beach floor 320.
Like the beach floor 320, the pool floor 310 illustrated in FIGS. 3 and 4B is sloped. In some embodiments, the pool floor 310 in the shallow pool area 250 is sloped at a shallow pool slope 410. The shallow pool slope 410 may form the same angle as the beach slope angle 420 (as in the straight transition illustrated in FIG. 3), but the angles need not be the same (e.g., FIG. 4B). In some embodiments, the shallow pool slope 410 is less than or equal to seven degrees from level. The shallow pool slope 410 is gentle enough to facilitate easy and safe walking access into and out of the pool 230 while being steep enough to quickly develop depth in the pool 230. The slope of pool floor 310 need not be uniform throughout the entire pool. In some embodiments (not shown), the slope of the pool floor increases in the interior pool area to develop the depth required for water activities such as swimming and diving within the interior pool area 330. In some embodiments, the depth of the water is great enough in interior pool area 330 to swim in. The depth of water within interior pool area 330 may also be deep enough in which to safely perform surface dives.
While FIG. 3 shows an example of a smooth transition between the pool floor 310 and beach floor 320, the transition may also be stepped or curved while still facilitating a walking pool entry to and exit from the pool 230 at the pool perimeter 210. FIGS. 4A & 4B illustrate examples of stepped and sloped transitions, respectively, that facilitate a walking entry/exit. Since these transitions do not have an abrupt drop-off or a steep slope, such transitions facilitate a walking entry to and exit from the pool 230 without requiring a straight or smooth transition at the pool perimeter 210. In some embodiments, the transitions shown in FIGS. 4A & 4B are used as alternatives to the smooth transition shown in FIG. 3. In other embodiments, the transitions illustrated in FIGS. 4A & 4B are incorporated into portions of the pool perimeter 210.
C. Gutter
In some embodiments, a gutter is formed about the outer perimeter of the island wave pool. FIG. 10A illustrates a cutaway side view of an island wave pool 200 featuring a gutter 1010. In some embodiments, the gutter serves several purposes. First, the gutter captures water spillage from waves in the pool 230, reducing or eliminating water overflow into the beach area 240. It is important to minimize water spillage onto the beach area 240 to keep beach-goers and their encampments dry. For a sand beach area, minimizing water spillage onto the beach area can prevent erosion of beach areas formed using sand and reduce the amount of sand entering the pool from the beach area. Second, minimizing water spillage onto the beach area may help protect certain beach surfaces from the destructive effects of prolonged contact with water, thereby increasing the lifetime of the material used to construct the pool-side beach area flooring.
FIG. 10B illustrates a top-view of the island wave pool 200 with a gutter 1010 formed about the pool perimeter 210. In some embodiments, the gutter 1010 further serves to reduce the backflow of wave energy into the pool 230. Without the gutter 1010, when a wave generated by the wave generator on the central island 220 reaches shore at the pool perimeter 210, momentum carries a volume of water beyond the static water line and up the slope of the beach area 240. Gravity eventually pulls the volume of water back to the static water line and into the pool 230. The momentum of this back-flowing water transfers a reverse wave energy into the pool 230. In some embodiments, this reverse wave energy is undesirable because it may increase the choppiness of the waves in the wave pool. The gutter 1010 minimizes this reverse wave energy by capturing the forward-moving water and preventing the captured water from flowing directly back into the pool 230. FIG. 10A shows a grate 1020 covering the gutter 1010 of some embodiments. The grate 1020 is typically constructed of a material such as metal, a high-strength plastic, or a composite material. The grate 1020 of some embodiments is slotted or otherwise perforated to allow water to pass through the grate 1020 and into the gutter 1010 while safely covering the gutter to prevent swimmers and beach-goers from tripping as they cross over the gutter. In some embodiments, a gutter return 1030 provides a return path for water that has entered the gutter to return to the pool 230. In some embodiments, the gutter return 1030 is sloped so as to allow gravity to drain the water from the gutter 1010 back into the pool 230. In other embodiments, a pump (not shown) is used to drain water from the gutter 1010 back into the pool 230. In yet other embodiments, overflow water collected in the gutter is diverted through pipes to a balance tank/surge pit (not shown). A circulation pump draws water from the balance tank/surge pit for filtration and chemical treatment, then returns the filtered and treated water to the pool 230 via a plumbing return distribution system (not shown).
In some embodiments, the reverse wave energy caused by back-flowing wave spillage and reflected waves is desired, for example, because maximum wave energy is the pool 230 is desired. In such cases, a gutter is not utilized in the construction of the island wave pool.
III. Central Island Wave Generator
As illustrated in FIGS. 2 & 3, the island wave pool 200 has a central island 220. In some embodiments, the central island 220 is the source of wave generation in the island wave pool 200. Waves may be generated from the central island 220 through various wave-generation methods. Some embodiments generate water waves using one or more water-filled caissons on the central island 220. In other embodiments, waves are generated using a water plow, a channel, and a reef on the central island 220. In yet other embodiments, other methods are used for wave generation.
A. Central Island Caisson Wave Generator
One method of generating waves in the pool 230 uses one or more caissons positioned on the central island 220. FIG. 5A illustrates a cutaway side view of one embodiment of the island wave pool 200 featuring a water-filled caisson 510 on the central island 220. FIG. 5A illustrates an air pump 520, an air pressure chamber 530, and an air valve 540 on the central island 220. In some embodiments, the caisson 510 is coupled to the pool 230 at the base of the caisson 510 and the bottom of pool 230. Except for the opening into the pool 230, the caisson 510 is sealed. The air pump 520 compresses air, which is stored in the air pressure chamber 530. As illustrated in FIG. 5B, when the air valve 540 is opened, a charge of pressurized air from the air pressure chamber 530 is vented into the upper portion of the caisson 510, forcing the water from the chamber into the pool 230 in a single forceful motion. The water expelled from the caisson 510 displaces water in the pool 230, producing a wave which propagates across the surface of the pool 230 toward the pool perimeter 210.
The central island 220 of some embodiments includes multiple caissons on the central island 220. FIG. 6 illustrates a top view of one embodiment of the invention featuring four distinct water-filled caissons 610, 620, 630, and 640 arranged about the perimeter of the central island 220. The bottom of each caisson is coupled to the pool 230 at the base of the particular caisson and the bottom of the pool 230. Except for the opening into the pool 230, each caisson is sealed. The air pump 520 compresses air, which is stored in the air pressure chamber 530. Here, the air valves 611, 621, 631, and 641 are associated with individual caissons 610, 620, 630, and 640, respectively. Each air valve can be opened separately, or the air valves can be opened simultaneously. When one of the air valves 611, 621, 631, and 641 is opened, a charge of pressurized air from the air pressure chamber 530 is vented into the upper portion of the associated caisson, forcing the water from the chamber into the pool 230 in a single forceful motion. The water expelled from the particular caisson displaces water in the pool 230, producing a wave which propagates across the surface of the pool 230 toward the pool perimeter 210.
Different wave effects in the pool 230 can be realized by opening the air valves 611, 621, 631, and 641 in different sequences. For example, the air valves 611, 621, 631, and 641 are opened in a repeated sequence, a continuous clockwise wave (as viewed from above) can be formed in the pool 230. The sequence could be reversed to produce a continuous counter-clockwise wave in the pool 230. Alternatively, the air valves 611, 621, 631, and 641 can be opened simultaneously to produce four simultaneous waves which merge to form a single circular wave expanding from the central island 220 toward the pool perimeter 210.
One of ordinary skill in the art would recognize that island 220 could be constructed using any number of caissons, and that any number of air pumps, air pressure chambers, and air valves could be utilized to achieve the desired result of generating waves. It would also be apparent to one having ordinary skill in the art that different sequences of air valve actuation could be used to achieve single or continuous clockwise or counter-clockwise waves, multiple simultaneous waves, standing waves, resonant waves, or other wave effects in the pool 230.
B. Central Island Plow, Channel, and Reef Wave Generator
One method of generating waves from the central island uses a plow to displace water from a water-filled channel on the island over a reef bounding the island and into the pool, generating a wave in the pool. In some embodiments, the channel and reef are formed in a ring about the perimeter of the central island. By forming the reef and channel in a ring about the central island, the plow may be drawn forward continuously through the water-filled channel to create waves, rather than using the back and forth motion of conventional push/pull wave generators (e.g., caisson wave generators). This continuous forward motion has advantages over conventional push/pull wave generators. For example, the continuous forward plow motion is more efficient than the conventional back and forth motion because continuous motion preserves the displaced water's forward momentum. After generating a wave, conventional wave generators utilizing successive forward thrusts to generate waves must break the forward inertia of one wave before generating a subsequent wave (or allow for a substantial delay for the forward inertia to dissipate). Since water has considerable mass per unit volume, breaking a wave's forward momentum requires tremendous energy. This energy is wasted because only the forward motion is useful for wave generation.
With continuous forward plow motion through a ring-shaped, water-filled channel and reef, breaking an initial wave's forward momentum is unnecessary because one continuous wave is generated as the plow circles the island in the water-filled channel. However, the swimmer in the pool experiences the same type of periodic wave as generated by the conventional push/pull wave generator because the plow repeatedly circles the central island, causing the continuously generated wave to periodically cross the swimmer's particular location in the pool.
1. Reef
FIG. 7 illustrates a cutaway side view of one embodiment of a plow, channel, and reef wave generator. FIG. 7 shows a reef 730 positioned on the outer boundary of the central island 220. A reef top 737 forms the top of the reef. The reef top 737 may be flat and level, as shown in FIG. 7. Alternatively, the reef top may be curved or sloped (not shown) to manipulate wave characteristics (i.e., size, shape, speed, and duration). The width of the reef top (i.e., the radial thickness of the reef 730) may also be adjusted to manipulate the characteristics of the waves formed thereon.
FIG. 7 also shows the water-filled channel 710 bounded by the reef 730. In some embodiments, waves are formed in the pool 230 by drawing a plow 720 through the water-filled channel 710, the plow pushing water from the channel 710 over the reef 730 and into the pool 230. In some embodiments, the water displaced from the channel 710 and into the pool 230 is refilled into the channel 710 form the pool 230 by gravity. For this reason, the height of the reef top 737 is important in some embodiments, as the reef top 737 must not be so high as to prevent gravity or wave spillage from refilling the channel 710 with water from the pool 230.
In some embodiments, the reef 730 enhances wave formation in the pool 230. For a central island wave generator with a plow in a channel and no reef rising above the channel floor at the outer perimeter of the central island, rotating the plow about the central island would form a wave in the pool 230, but the wave's characteristics (i.e., size, shape, speed, and/or duration) could be undesirable (e.g., undesirably long length and/or short height). A reef at the outer perimeter of the central island may be used to form waves with desirable characteristics (e.g., short length and/or high amplitude). When the plow 720 is rotated about the central island 220 in the water-filled channel 710, the plow 720 displaces water from the water-filled channel 710 toward the reef 730. The reef 730 deflects the displaced water upward and over the reef 730. By blocking the horizontal and downward paths that the displaced water would otherwise take, the reef focuses the energy upward into that water displaced over the reef 730. By blocking the horizontal and downward paths, the reef 730 reduces the volume of water displaced by the moving plow 720, but since energy is conserved, the energy density of the volume of water displaced over the reef 730 is increased. As the displaced water flows over the reef, some or all of the water rises above the static water line 770. Before the displaced water drops into the pool 230, its energy density will be further enhanced as gravity acts to pull the water into the pool 230. As the displaced water enters the pool 230, a wave with desirable characteristics (e.g., short length and/or high amplitude) is formed in the pool 230 due to the energy density increase caused by the reef. Therefore, while the reef top 737 must not be so high as to prevent the channel 710 from refilling with water from the pool 230, the reef top 737 must also not be so low as to negate the reef's wave-enhancing effect. When the reef top 737 is sufficiently below the static water line 770, gravity alone is sufficient to refill the channel 710 because, on average, the water level of the pool is above the reef top 737 and water from the pool 230 flows freely into the channel 710 by gravity. When the reef top 737 is equal to or slightly above the static water line 770 (e.g., five centimeters above the static water line), residual wave energy in the pool 230 can cause sufficient spillage over the reef top 737 at a rate adequate to keep the channel 710 filled with water, even as the rotating plow 720 continuously displaces water from the channel 710.
In some embodiments, the reef top 737 is positioned at a height between 55 percent and 75 percent of the distance between the channel floor 715 and the mean water line. In other embodiments, the reef top 737 is positioned at a height between 75 percent and 95 percent of the distance between the channel floor 715 and the mean water line.
One of ordinary skill in the art would appreciate that other methods of refilling the channel 710 with water may be practiced without departing from the spirit of the invention. Such methods include both gravity-fed and powered refilling methods. An example of an alternate gravity-fed refilling method involves using a slotted reef, where slots formed in the reef (not shown) below the static water line and between the pool and channel enable the channel to be refilled with water from the pool while allowing for the reef top to be close to, at, or slightly above the static water line. An example of a powered method of refilling the channel involves using an electric water pump to refill the channel with water from the pool.
FIG. 7 illustrates the reef slope 735 formed by the inner sidewall of the reef 730 of some embodiments. In some embodiments, the inner sidewall of the reef forms a vertical wall (perpendicular to the level reef top 737). However, it is preferred that the reef slope 735 is sloped, as shown if FIG. 7, at an angle other than perpendicular to the level reef top 737. The slope illustrated in FIG. 7 helps to direct water displaced by the plow 720 over the reef 730. As the plow 720 displaces water from the water-filled channel 710 toward the reef 730, the slope 735 acts as a ramp that efficiently channels and focuses the wave energy toward the reef top 737. The angle formed from perpendicular by the slope 735 may be varied to achieve different wave characteristics (i.e., wave size, shape, speed, and/or duration). Wave characteristics may also be tuned by varying the shape (e.g., curving the shape) of the reef slope 735.
2. Channel
FIG. 7 illustrates the water-filled channel 710 formed on the central island 220 adjacent to and bounded by the reef 730. The channel 710 is a water reservoir. The channel bottom 715 is positioned below the static water line 770 of the pool to allow a plow 720 to be drawn through the channel 710 below the static water line. The water stored in the channel 710 is displaced over the reef 730 and into the pool 230 by the plow 720. The displaced water entering the pool 230 generates a wave in the pool 230. As the plow 720 displaces water from the channel 710 into the pool 230, the water level in the channel 710 may fall below the static water line of the pool. When the water level in the channel falls below the static water line, gravity refills the channel 710 with water from the pool 230.
As the plow 720 is drawn in the channel, some of the water in front of the plow 720 is displaced over the reef 730. However, some of the water in front of the plow that is not displaced over the reef 730 is simply pushed forward in the channel in the direction of the plow's forward movement. The forward movement of the plow 720 also causes a drag that draws water behind the plow in the direction of the plow's forward rotation about the central island 220. The result is that the movement of the plow 720 in the channel 710 tends to cause a water current flow to form in the channel 710 in the direction of the plow's movement.
Generally, the faster the plow's forward movement in the channel, the larger the wave generated. Thus, the effect of the water current flow in the channel 710 is to reduce the wave generation effectiveness of the plow's forward movement because the water current flow (moving in the same direction as the plow) reduces the effective speed of the plow 720 relative to the water in the channel 710. However, the loss of plow effectiveness can be mitigated by taking steps to reduce the forward current flow of the water in the channel 710.
There are many ways to reduce, eliminate, or even reverse the water current flow within the channel 710. In some embodiments, baffles, vertical slats, dimples, serrations, or other irregularly shaped obstructions (not shown) are placed on the channel bottom 715 to increase drag on the water flowing in the channel 710. In some embodiments, a water pump (not shown) is used to direct water in the direction opposite that of plow movement in the channel 710 to reduce water current flow. As illustrated in the example embodiment of FIG. 7, the channel bottom 715 may be flat. However, the channel bottom 715 may be formed using various shapes (e.g., curved, sloped, or rippled) to accommodate various plow shapes, to restrict current flows, and to otherwise manipulate the flow of water within the channel 710.
In some embodiments, gravity is exploited to reduce undesirable forward channel current flow. As the plow 720 displaces water from the channel 710 into the pool 230, gravity refills the channel 710 with water from the pool 230. The water refilling from the channel 710 from the pool 230 flows into the channel 710 largely perpendicular to the direction of the channel current, thereby impeding the channel current flow.
3. Plow
As illustrated in FIG. 7, a plow 720 extends below the surface of the water within the channel 710. In some embodiments, the plow 720 is fixed to an armature 750. The armature 750 is attached to a motor 740 capable of drawing the plow 720 in the channel 710 in a circular fashion about the central island 220. FIG. 8 illustrates a top view of the central island 220 within the pool 230. The circular path 810 of the plow 720 about the central island 220 is shown in FIG. 8. In some embodiments, as shown in FIG. 8, the motor 740 draws the plow 720 about the central island 220 in the channel 710 in a counter-clockwise direction. In other embodiments, the motor 740 draws the plow 720 about the central island 220 in the channel 710 in a clockwise direction. In yet other embodiments, the motor 740 is reversible, and is capable of selectively drawing the plow 720 in either a clockwise or counter-clockwise direction about the central island 220.
FIG. 11 illustrates a side view of the central island 220, including the armature 750 and plow 720. The arrow in FIG. 11 shows the direction of the plow's movement in some embodiments. The plow 720 depicted by the solid lines in FIG. 11 is oriented vertically, or at zero degrees from vertical. In some embodiments, the plow 720 is angled downward, as depicted by the dashed lines in FIG. 11, at a positive angle 1110 from vertical. In other embodiments, the plow 720 is angled upward, at a negative angle 1110 from vertical. Adjusting the vertical angle 1110 of the plow 720 modifies the characteristics of the waves generated by the wave generator. For example, experimental results show that for a given plow velocity, a positive angle 1110 for the plow 720 generates a higher intensity wave than when the plow 720 is positioned vertically (i.e., when the plow 720 is positioned an angle 1110 of zero degrees).
FIG. 12 illustrates a top view of the central island 220, including the armature 750 and plow 720. The arrow in FIG. 12 shows the direction of the plow's rotation in some embodiments. The plow 720 depicted by the solid lines in FIG. 12 is oriented radially. In other words, angle 1210 forms a zero degree angle from the radius 1240 drawn from the axis of rotation 1220 through the plow pivot point 1230. In some embodiments, the plow 720 is angled outward, as depicted by the dashed lines 1250 in FIG. 12. In other words, the plow is positioned at a positive angle 1210 from the radius 1240. Adjusting the radial angle 1210 of the plow 720 modifies the characteristics of the waves generated by the wave generator. For example, experimental results show that for a given plow velocity, a positive angle 1210 for the plow 720 generates a higher intensity wave than when the plow 720 is positioned radially (i.e., when the plow 720 is positioned an angle 1210 of zero degrees).
As illustrated in FIGS. 13A & 13B, the plow 720 may take various shapes. FIG. 13A illustrates a flat plow 720 fixed to the armature 750. FIG. 13B illustrates a curved plow 720 fixed to the armature 750. Different shaped plows may be used to adjust the characteristics of the waves generated by the wave generator. For example, some experimental results show that for a given plow velocity, a flat plow is more effective than a curved plow for producing high intensity waves.
In some embodiments, the plow, channel, and reef wave generator has multiple plows. While a single plow may be used, it may be advantageous to use multiple plows distributed in a balanced manner about the axis of rotation. FIG. 14 illustrates one embodiment of such a wave generator with three plows 1410 distributed about the axis of rotation 1220 at equal angles 1430. Since each armature 1420 and plow 1410 forms a lever, balancing the angular distribution of the plows about the axis of rotation 1220 (i.e., 120 degrees apart for each of three plows) allows the torque generated by the motor to be distributed evenly, reducing the stress placed on the motor and the motor's support structure.
FIG. 15 illustrates one embodiment in which multiple plows 1530 are used. In this example embodiment, the angles 1510 and 1520 are distributed about the axis of rotation 1220 in a balanced manner, but angle 1510 is different from angle 1520. A wave generator configured in this fashion produces periodic sets of waves.
The variable attributes listed above, such as plow angles and angular distribution of multiple plows, may be combined to generate sets of waves with desirable effects. For example, FIG. 15 illustrates plows 1530, 1540, 1550, and 1560 arranged in a balanced angular distribution about the axis of rotation 1220. Since angle 1510 is smaller than angle 1520, this wave generator generates two pairs of continuous waves about the central island 220, as shown in FIG. 15. By individually configuring the vertical and radial angles of plows 1530-1560, the wave characteristics of each of the four continuous waves generated can be customized.
4. Plow, Channel, and Reef Wave Generator Operation
The plow 720, channel 710, and reef 730 on the central island 220 work in unison to safely and efficiently generate waves in the pool 230. When the motor 740 sweeps the plow 720 through the water-filled channel 710, the plow 720 displaces water from the channel 710 and the reef 730 focuses the displaced wave's energy over the reef 730, causing at least some of the displaced water to rise above the pool's static water line 770. The momentum of the displaced water carries it over the reef 730. Gravity combines with the water's momentum to deliver the displaced water into the pool 230. The displaced water entering the pool 230 displaces water already in the pool, forming a wave in the pool 230. This wave travels outward from the central island 220 and through the pool 230 before reaching the pool perimeter 210. In addition to focusing the water's energy, the reef 730 blocks reflected wave energy from flowing from the pool 230 backward into the channel 710, maximizing the wave energy transferred into the wave recreation area 230 and minimizing channel turbulence.
FIG. 8 shows a top view of a central island 220 incorporating a plow, channel, and reef wave generator. As illustrated in FIG. 8, the reef 730 forms a ring on the outer perimeter of the central island 220. The channel 710 forms a ring within the reef 730. As illustrated in FIGS. 7 & 8, at least a portion of the plow 720 is positioned below the static water line as the plow 720 is drawn continuously in a circular fashion within the channel 710 adjacent to the reef 730. The forward movement of the plow 720 displaces the water in front of the plow 720, forcing water over the reef 730 and into the pool 230, causing a wave to form therein.
5. Motor Support Structure
FIG. 7 illustrates the support 760 of some embodiments. The function of the support 760 is to support the motor 740 and to keep the motor dry. As illustrated in FIG. 7, in some embodiments, the support 760 rises above the static water line but is hollow inside, allowing the motor 740 to be positioned below the static water line 770 and out of sight within the hollow support 760 while staying dry. In other embodiments (not shown), the support 760 projects above the static water line 770 of the island wave pool 200, holding the motor 740 above the static water line 770, where it is kept dry. The support 760 need not have the cylindrical shape illustrated in FIG. 7. The support 760 for the motor 740 can be any conventional structure that keeps the motor dry and holds the motor in a position that allows the it to rotate the armature 750 such that the plow 720 is drawn in a circular fashion, when viewed from above, within the channel 710.
6. Motor
The motor 740 may be any type of conventional motor capable of sustaining rotation. Gasoline and electric motors may be used, but the proximity of the motor to water may make their use prohibitive. One preferred method uses a combination of an on-shore electric motor and pneumatic drive system. FIG. 9 illustrates the electric/pneumatic drive system of some embodiments. The electric/pneumatic drive system has an electric motor 910 positioned in a dry, on-shore location a safe distance from the pool 230. When turned on, the electric motor 910 drives an air pump 920. The air pump 920 delivers compressed air to a pneumatic motor 940 located on the central island 220 through a feed line 930. The compressed air delivered to the pneumatic motor 940 rotates the motor's drive shaft 950, which in turn rotates the armature 750 and plow 720 to generate waves. In some embodiments, a gear-reduction mechanism or gear box is positioned between the motor's driveshaft and the armature.
The motor 910 need not be an electric motor, and any type of conventional motor can be used to drive the air pump 920. For instance, the motor 910 may be a gasoline or diesel engine.
Additionally, the pump 920 need not be an air pump, and the motor 940 need not be a pneumatic motor. Instead, any conventional means of transferring energy at a distance may be used to provide power to the motor 940 from the safety of shore. For example, a hydraulic drive system may be used. A hydraulic drive system may require a hydraulic fluid return line 935 as illustrated in FIG. 9. In another embodiment, a driveshaft is used to transfer power from a shore-based motor to the rotating apparatus on the central island 220. In yet another embodiment, a belt drive is used (not shown).
C. Safety
Safety is an issue of utmost concern in any water amusement attraction. The island wave pool incorporates numerous safety features in addition to those previously described. In some embodiments, the island wave pool has a shark cage that prevents swimmers in the pool from coming into contact with the wave generation apparatus on the central island. FIG. 16 illustrates the shark cage 1610 of some embodiments. The shark cage 1610 is positioned on top of the outer perimeter of the central island 220. The shark cage 1610 extends high enough above the central island 220 (e.g., eight feet or 2.5 meters) so as to impede swimmers in the pool from climbing over it and entering the central island 220. The shark cage 1610 may be constructed using any material porous enough to allow water and wave energy to pass through it while preventing people from passing through (e.g., nylon netting, chain link fence, closely spaced metal rods, etc.)
In some embodiments, the perimeter of the central island 220 is outfitted with elevated lifeguard towers. FIG. 16 illustrates the lifeguard towers 1620 of some embodiments. Several lifeguard towers are positioned about the outer perimeter of the central island 220 to provide coverage for the entire pool. Positioning the lifeguard towers about the central island 220, adjacent to the deeper area of the pool 230, offers the advantage of closer proximity to potential trouble spots than beach-based lifeguard towers provide. FIG. 17 illustrates a top view of the central island 220 with lifeguard towers 1620 positioned at key points about the perimeter of the central island 220.
While the present invention has been illustrated by description of several embodiments and while the illustrative embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant's general inventive concept.
