WO2009064445A1

WO2009064445A1 - Method and apparatus for varying water flow for stationary sheet flow water rides

Info

Publication number: WO2009064445A1
Application number: PCT/US2008/012758
Authority: WO
Inventors: Thomas J. Lochtefeld
Original assignee: Lochtefeld Thomas J
Priority date: 2007-11-13
Filing date: 2008-11-13
Publication date: 2009-05-22
Also published as: US20090169305A1

Abstract

The invention relates to a water ride with adjustable nozzles for adjusting the speed and depth of the flow of water emanating from the nozzles and onto the ride surface. The nozzles have a bladder that can be used to adjust the height of the opening and therefore the depth of the water flow. More than one adjustable nozzle can be used to vary the flow effects across the width of the ride surface. Additional adjustment bladders can be provided underneath the inclined portion of the ride surface, wherein by adjusting each bladder independently, the tilt of the ride surface transverse to the direction of flow can be adjusted.

Description

METHOD AND APPARATUS FOR VARYING WATER FLOW FOR STATIONARY SHEET FLOW WATER RIDES

Field of the Invention

The present invention relates to the field of simulated surfing apparatuses and methods, and in particular, to a method and apparatus for varying the depth of a flowing body of water in connection with a water ride having a contoured or inclined ride surface, wherein by regulating the depth and speed of flow in relation to the area and angles of incline, novel flow dynamics can be generated for rider controlled water-skimming activities, including those analogous to the sport of surfing. Background of the Invention

Sheet flow water rides have become popular in recent years. The technology that Applicant has previously developed which is referred to as a FlowRider® relates to a standing wave water attraction comprising nozzles that are adapted to inject a sheet flow of water under pressure onto a contoured or inclined ride surface (being optionally made into the shape of a wave). By injecting water under pressure onto such surface at the proper speed and depth, the sheet flow can become supercritical (based on the Froude Number), which causes the water to conform to the contours of the ride surface while being supported by the flow bed without breaking up. This allows a rider with a special board to perform skimming and simulated surfing maneuvers on an inclined ride surface by using the force of gravity to overcome the upward momentum created by the flow, wherein the rider can attempt to oscillate back and forth, around a point of equilibrium, to achieve maneuvers of interest.

The reason that the above referenced sheet flow water ride can succeed in its objectives is that it does not duplicate naturally breaking progressive waves, rather, it creates "flow shapes" from high velocity sheet flows over a suitably shaped forming surface. The majority of flow manifestations created thereby cannot technically be called waves. They may appear like gravity waves breaking obliquely to a beach; however, these sheet flow manifestations are distinct hydrodynamic phenomena caused by the interaction of four dynamics: (1) unique surface architecture; (2) the trajectory of the water relative to the flow forming surface; (3) flow separation from this surface using a containerless surface; and (4) changes in hydraulic state of flow

(i.e., supercritical, critical or sub-critical) upon this surface.

Another important feature of the previous invention is that the preferred water flow type was a relatively thin "sheet" flow, rather than the relatively deep water utilized in wave pools and other prior art water rides. A thin sheet flow is where the water depth is sufficiently shallow such that the pressure disturbance caused by a rider and his board is influenced by the riding surface through a reaction force, whose effects on the rider and board are generally known as the "ground effect." With a thin sheet flow, the board is relatively close to a solid boundary, i.e., the flow bed, so that the pressure disturbance from the board does not have time to diminish before it comes into contact with the solid boundary. This results in the pressure disturbance transmitting through the fluid directly to the ground, and allows the ground to participate, as a reaction wall, against the weight of the rider. From an accomplished rider's perspective, the ground effect offers improved performance in the form of responsive turns, increased speed, and tighter radius maneuvers resulting from lift augmentation that enables a decrease in vehicle planing area.

In this regard, it should be pointed out that even with a relatively deep sheet flow on an inclined ride surface, no wave is necessarily required for a rider to enjoy a water attraction constructed in accordance with these principals. All that is required is an incline of sufficient slope and angle to allow the rider to slide down the upwardly sheeting flow due to gravity. Furthermore, intentional rider-induced drag can slow the rider and send him or her back up the incline to permit additional maneuvers. Likewise, if desired, the rider can achieve equilibrium (e.g., a stationary position with respect to the flow) by regulating his drag relative to the sloped water flow.

Previously, attempts were made to change the nature and character of the sheet flow to vary the rider's experience by varying the slope or configuration of the ride surface, and/or changing the speed of the flowing body of water, or providing an undulating pliable floor with adjustable bladders as shown in Applicant's U.S. patent no. 6,716,107. By making these modifications, the water ride could be adapted to create various flow effects, including hydraulic jumps, critical flows, and sub-critical flows, which could be used to increase interest and enhance the rider's experience, and advantageously allow the water ride to be multi-faceted in its appeal to a wide range of skill levels, including from beginner to expert. For example, the previous invention taught that the velocity of an upwardly inclined supercritical sheet flow could be reduced so that its kinetic energy would become less than the gravitational potential energy, wherein, a hydraulic jump could be created prior to reaching a downstream ridge line, wherein, additional white water could be formed and an effect similar to a stationary white water bore could be created on the ride surface. The relative position of the hydraulic jump on the incline could be determined by adjusting the velocity of the supercritical flow, i.e., the higher the velocity, the higher the position of the hydraulic jump.

Two distinct velocities could also be created and issued so that two subsequent coexisting hydraulic states could be created on the ride surface, i.e., a higher velocity supercritical flow could be created on one side that could flow over the top of the ridge line, and an adjacent lower velocity supercritical flow could be created on the other side that transitioned to a hydraulic jump and white water bore as the supercritical flow decelerated to a sub-critical flow before reaching the ridge line. These cross-stream velocity gradients were created by placing multiple flow sources of differing kinetic energy side by side and simultaneously projecting them upslope.

Another adjustment method contemplated previously was creating a cross- stream gradient by configuring a single source (e.g., pump) with a specially configured angled nozzle or plenum. In such case, the nozzle was created with an angled asymmetrical aperture comprised of an asymmetrical wide side and an asymmetrical narrow side, capable of producing flows that exhibited a hydrostatic tilt. In this manner, the supercritical flow that issued from the wide side was thicker (e.g., deeper) than the flow that issued from the narrow side, which was thinner (e.g., shallower). Thus, a variable subsequent coexisting hydraulic state could be formed, i.e., the supercritical flow that issued from the wide side of the aperture would clear the downstream ridge line and sustain its supercritical character, while the flow that issued from the narrow side of the aperture subsequently suffered a hydraulic jump and exhibited white water at a lower elevation on the contoured incline. Another general approach to modifying the pressure gradient which avoided penetrations and discontinuity on the ride surface was accomplished through the adjustment of hydrostatic pressure, which can be accomplished by creating an angled asymmetrically extended downstream ridge line of increasing elevation. Thus, two subsequent coexisting hydraulic states could be formed, i.e., the supercritical flow that flowed over the shortened side cleared and sustained its supercritical character, while the flow that flowed over the higher side had insufficient kinetic energy to clear the extended ridge line and subsequently suffered a hydraulic jump and exhibited white water at a lower elevation. Notwithstanding these attempts to modify the nature and character of the sheet flow, using adjustable flow rates, velocities and pressures, and unique ride surface configurations, as set forth in Applicant's previous Patent No. 5,899,633, the intent was to produce a sheet flow of water having an initial supercritical flow having a relatively constant depth or configuration. Although the previous invention contemplated that a relatively deep flow could be produced in addition to a relatively shallow flow, that patent significantly touted the advantages and benefits of producing a relatively thin flow, which, in actual practice, was only about three to four inches in depth. Therefore, in the absence of a means of adjusting the depth of flow created by the nozzle, the full advantages of the water ride could not be recognized. That is, if a water ride attraction was built so that it produced only a deep flow of water, none of the many advantages contemplated by the Applicant in association with producing a relatively thin sheet flow could be achieved. Likewise, if a water ride attraction was built to produce only a shallow sheet flow, the rider could not use a standard surfboard, and therefore, could not learn the skills necessary to master traditional surfing.

In this respect, one of the drawbacks of the previous sheet flow apparatus was that special boards with no fins were required to be developed and used in conjunction with the water ride. Because of the shallow nature of the thin sheet flow, close proximity of the board to the solid boundary, and consequences of the ground effect, it was heretofore not possible to use a standard surfboard with a fin extending down which would effectively cause the board to "ground out" on the flow bed and make it impossible to perform freely on the flow. This disadvantageously did not allow riders to train and learn how to surf using standard surfboards, which made the transition from using the special sheet flow board to using a real surf board, and therefore, from riding on the sheet flow water ride to surfing on real ocean waves, more difficult to achieve.

Summary of the Invention The present invention relates to a water ride having an adjustability feature that enables the depth of the flowing body of water being propelled onto an inclined or contoured ride surface to be easily adjusted. The adjustability feature is preferably used in conjunction with the sheet flow water ride technology previously developed by Applicant which has been described above, as well as a relatively deep sheet flow variation of it (which will collectively be referred to as a "sheet flow water ride" for simplicity purposes), which includes an inclined or contoured ride surface upon which the sheet flow of water is propelled. The present adjustability feature preferably enables the depth of the sheet flow to be adjusted, such that by itself, or in conjunction with other adjustability features, including the adjustment of the flow speed, or incline and/or tilt of the ride surface, a variety of dynamic changes to the nature and character of the sheet flow can be created, thereby giving riders a chance to experience a wide range of flow conditions, including relatively shallow and deep flows on the same ride surface.

Generally speaking, the present invention comprises nozzles with an adjustable aperture capable of releasing a sheet flow of water under high pressure onto the associated ride surface at varying depths. The nozzle component preferably comprises a pump with an inlet capable of drawing water in from a source, wherein the water is placed under high pressure and allowed to be channeled through a narrowing nozzle aperture, and then released. The aperture is configured so that water is extruded through the nozzle and forms a focused-propulsion of water that rapidly disperses onto the ride surface, and forms a continuous sheet flow of water thereon, wherein by adjusting the effective height of the aperture, the depth of flow can be adjusted.

Unlike previous nozzles, the present invention preferably comprises an elastic bladder under pressure which can cause a hinged plate that extends down into the nozzle opening to be lowered, and thereby, allow the height of the opening to be adjusted. Whereas the preferred nozzle opening has a relatively tall internal dimensional height when compared to previous nozzle openings (so that relatively deep sheet flows can be created), an adjustment feature is preferably provided which can be used to adjust the effective height of the opening, and thereby, adjust the height of the flow. Other adjustment means to control the movement of the hinged plate, such as hydraulic and electromechanical control devices, are also _^contemplated.

The hinged plate is preferably hinged at the top on the inside surface of the opening so that it can swing down from its uppermost position to its lowermost position. With the hinged plate in its uppermost position, the opening is maximized to allow the maximum depth of flow to be extruded, while with the hinged plate in its lowermost position, the opening and therefore the depth of flow is minimized. In this fashion, by adjusting how far down the hinged plate is permitted to be lowered, which can be done by adjusting the pressure in the bladder, the depth of flow can also be adjusted.

It should be noted that as the water is propelled under pressure, the hinged plate would normally lift up by the force of the water being released, but as the bladder is inflated, the hinged plate is forced down, and lowered into the path of the flow. And by adjusting the amount of pressure in the bladder, and therefore, the extent to which the hinged plate is lowered and allowed to interfere with the flow travel path, the depth of flow is made adjustable. And because the depth of the flow is dependent on the effective height of the opening through which the water is allowed to pass, the flow depth can be adjusted simply by adjusting the bladder.

These adjustments can facilitate adjustments in the nature and character of the sheet flow of water propelled onto the ride surface. For example, by decreasing the depth of flow, a relatively thin sheet flow of water, traveling at an increased velocity, similar to those contemplated by the previous invention, can be created on the ride surface. On the other hand, by increasing the depth of flow, a relatively deep sheet flow of water can be created on the same ride surface, which can enable riders to use standard surfboards with fins. Likewise, by having two or more adjustable nozzles side by side, a portion of the flow can be made to enter the ride surface at one depth, and another portion of the flow can be made to enter the ride surface at another depth, which can create varied flow effects, including a hydraulic jump on one side, and supercritical flow on the other, even across a level ridge line.

Although these variations can be made without having to make any other adjustments, the present invention contemplates that these adjustments can be combined with other adjustments, such as to the flow speed, or inclination or tilt of the ride surface, wherein the adjustability and variability of the flow can be increased and enhanced, and an increased variety of dynamic flow changes and hydraulic states can be produced, which can further enhance and add variety to the rider's experience. For example, in addition to creating two hydraulic states across the ride surface based on flow depth variations, the speed with which the flow enters onto the ride surface within these hydraulic states can also be varied. Moreover, the inclination of the ride surface upon which these hydraulic states are created can be increased, decreased, or even tilted, thereby further varying the flow effects. This way, the degree to which these hydraulic states can form, dissipate, change in shape, change in size, and move around on the ride surface, etc., can be easily modified and varied.

Another related advantage is the ability of these adjustments to solve the transient surge problems associated with ride start-up and rider induced flow decay upon upwardly inclined flow surfaces. Because the flow depth can be controlled precisely, and because whether a particular flow remains supercritical is a function of flow depth, these adjustments preferably provide a means for self-clearing undesirable transitory surges and excess white water, which can help correct the problems associated with start-up and flow decay. Other advantages of the present invention will become apparent from the following description taken in conjunction with the drawings included herewith.

Brief Description of the Invention

FIGURE 1 is a plan view of the sheet flow water ride attraction with the adjustable nozzle feature of the present invention; FIGURE 2 is a section view of the sheet flow water ride shown in Figure 1 ;

FIGURE 3 is an isometric view of the sheet flow water ride shown in Figure 1 ; FIGURE 4 is a section view of the adjustable nozzle feature of the present invention with the bladder deflated and the hinged plate in its uppermost raised position; FIGURE 5 is a section view of the adjustable nozzle feature of the present invention with the bladder inflated and expanded, and the hinged plate in its lowermost closed position;

FIGURE 6 is an isometric view of the nozzle of the present invention FIGURE 7 is a plan view of the nozzle of the present invention; and FIGURE 8 is a detail of the bladder of the present invention.

Detailed Description of the Invention

Figure 1 shows an overhead view of an embodiment of the sheet flow water ride of the present invention preferably having two water injection nozzles 1 , a ride surface 3, recovery area 5, sidewalls 7, walkways 8, stairs 9, upper entry area 10, and lower entry area 12. As can be seen in Figures 2 and 3, immediately below injection nozzles 1 , ride surface 3 preferably has a down slope feeding area 11 , followed by horizontal section 13, which is followed by inclined section 15, which has a ridge 17 and a declining area 19. Below and downstream from inclined section 15 is preferably recovery area 5, with grates 21 , which allows run off water to pass into cavity 23 below, wherein grates 21 support riders exiting from ride surface 3. All surfaces around ride surface 3 are preferably padded or otherwise made of resilient material to provide a measure of safety to riders.

As seen in Figure 2, entire ride surface 3 is preferably suspended above an underground pool of water 29 such as by beams 25. Underground pool 29 is preferably the source of water for feeding water back onto ride surface 3 via injection nozzles 1. After water flows onto ride surface 3, and exits downstream from inclined section 15, and passes through grates 21 , and into cavity 23, water is allowed to pass back through gate 24, and then into pool 29, where the water is stored. Water in pool 29 can then be re-circulated back through inlet 31 , by pump 33, onto ride surface 3, via injection nozzles 1 , and then back into cavity 23 via recovery area 5 and grates 21. Pool 29 can be constructed much like any standard swimming pool, using concrete, etc., or any other conventional method. Ride surface 3 is preferably covered with padding or is made of flexible material to provide a cushioning effect to prevent injury to riders.

Inclined section 15 is preferably adjustable and supported underneath by one or more bladders 27 which are in turn supported by floor 26. The bladders can be made of elastic material such as rubber or other conventional material and are connected to a pump that allows the pressure inside to be adjusted. This way, the height of inclined section 15 can be adjusted by inflating and deflating bladders 27. Preferably, there are two or more bladders side by side under inclined section 15 which are independently inflatable and adjustable such that inclined section 15 can be tilted in a direction transverse to the flow of water. Figure 1 shows three bladders 27 (in dashed lines) positioned side by side, but it can be seen that two bladders could be used, or more than three. By independently adjusting the pressure of each bladder, such as by increasing the pressure in one bladder and decreasing the pressure in another bladder, a variable tilt can be created.

Inclined section 15 is preferably made to pivot about an upstream hinge 16 extending transverse to the flow, such that inclined section 15 can be raised or lowered through a range of motion preferably 12" to 24" or more in height. Inclined section 15 is preferably made of a flexible material such that it can flex and tilt sideways depending on which of the multiple bladders 27 is inflated more. For example, when two bladders side by side are used, by raising the left bladder higher than the right bladder, the left side of inclined section 15 can be tilted higher than the right side, and vice verse. This advantageously enables variable and dynamic flow effects to be created on ride surface 3 as discussed. For example, a variable pressure gradient can be created by independently adjusting bladders 27, wherein water flowing over the low side can travel at a supercritical speed up and over inclined section 15, whereas, water flowing over the high side could decelerate and produce a hydraulic jump and white water when it reaches critical and then sub- critical speed. Although two bladders 27 are preferably provided to adjust the tilt of inclined section 15, it can be seen that when three or more bladders are used, the tilt of inclined section 15 might be more accurately controlled. In this embodiment, ride surface 3 can be adapted to have sidewalls 7 extended along the edges of ride surface 3, which can help to contain water flow in a longitudinal direction. While in Applicant's previous sheet flow water rides, it was desirable to provide a containerless ride surface to avoid potential boundary layer effects and hydraulic interference caused by friction, the present invention is less concerned about such conditions and effects. With a deeper flow of water, the flowing body of water on ride surface 3 is able to have more power and momentum and thus is more able to muscle through the boundary layer effects and hydraulic interferences caused by friction, and therefore, is less susceptible to disruption from sidewalls 7. Although ride surface 3 of the present invention can be made without sidewalls, and be more like the containerless ride surfaces of the previous invention, particularly when a thin sheet flow of water is desired, for the above reasons, this is not necessarily required.

Figures 4-8 show various aspects of nozzle water extrusion equipment 30. Each nozzle 1 preferably has an inlet 31 at the bottom communicating with a water source, i.e., such as the water in pool 29, such that water from the source can be drawn by pump 33 into chamber 35. Inlet 31 is preferably extended below the surface of the water in pool 29, as shown in Figure 2. Pump 33 can be any conventional type with sufficient power to draw water into chamber 35 at the appropriate rate, velocity and pressure, and to make adjustments thereto, suitable for the appropriate size of water ride being constructed and operated. Pump 33 and other nozzle equipment 30 are preferably constructed using stainless steel or other durable and non-corrosive material.

As shown in Figures 4 and 5, above chamber 35 is preferably a bend 34 in duct 39 that causes water flowing upward through chamber 35 to bend forward and then slightly back down at an angle. This way, water in chamber 35 can flow through an aperture or opening 37 of nozzle 1 at the appropriate angle onto ride surface 3. The angle of trajectory created by opening 37 is preferably substantially the same as the angle of sloped feeding area 11 located upstream on ride surface 3, which allows the flow of water introduced onto ride surface 3 to be at the appropriate angle and helps to reduce disruption of flow.

Duct 39 preferably becomes progressively narrower toward the distal end where opening 37 is located, such that as water within chamber 35 is forced upward by pump 33, the water will be placed under greater pressure, wherein the water can be extruded through opening 37. This way, the water extruded through opening 37 will be under increased pressure and therefore released with increased velocity.

The adjustment feature of the present invention preferably comprises an inflatable bladder 45, as shown in Figure 8, preferably made of elastic material such as rubber positioned between an upper fixed wall portion 43 of duct 39, and a hinged plate 41 pivotally connected to an inside surface of opening 37. Hinged plate 41 is preferably pivoted about a hinge such that it can swing down into the flow path of Opening 37, from an uppermost position as shown in Figure 4, to a lowermost position as shown in Figure 5. Hinged plate 41 is preferably configured with a width and length so that it fits relatively snug inside the dimensions of opening 37 and can substantially block off the flow path within opening 37 when hinged plate 41 is in its lowermost position. Nevertheless, it should be seen that virtually any degree of motion is contemplated. It can be seen that the degree to which hinged plate 41 drops down and therefore interferes with the flow path of water through opening 37 will determine the height of opening 37 and therefore the depth of the water flow created by injection nozzle 1. Hinged plate 41 preferably swings down from above whereas the bottom of opening 37 preferably remains in a substantially fixed position.

Without taking into account the presence of bladder 45, hinged plate 41 is preferably adapted to freely pivot so that without any water pressure inside chamber 35 and against injection nozzle 1 , hinged plate 1 would be free to fall to its lowermost position. On the other hand, the present invention contemplates that when water pressure inside chamber 35 and against injection nozzle 1 is sufficient enough, hinged plate 41 would be forced upward and against fixed wall portion 43 to its uppermost position, thereby maximizing the effective size of opening 37. The adjustability of hinged plate 41 is preferably controlled by inflating and deflating bladder 45, which is preferably held between fixed wall portion 43 and hinged plate 41 , as shown in Figure 5. By inflating bladder 45, it will effectively expand and bias hinged plate 41 downward toward its lowermost position, which when achieved, effectively closes off opening 37. On the other hand, when bladder 45 is completely deflated, it allows hinged plate 41 to be pivoted upward to its uppermost position, by virtue of the pressure exerted against hinged plate 41 as water is extruded through chamber 35 and passage 34.

It can be seen that by adjusting the degree to which bladder 45 is inflated or deflated, the degree to which hinged plate 41 is pivoted, and therefore, the degree to which opening 37 is opened or closed, can be adjusted. For example, if bladder 45 is inflated halfway, hinged plate 41 would be lowered halfway, and therefore, the effective height of opening 37 would be about halfway as well, in which case, the depth of the water flow generated by nozzle 1 would be about half its original depth. Likewise, if bladder 45 is inflated to a quarter of the way, hinged plate 41 would be lowered a quarter of the way, and therefore, the effective interior height of opening 37 would be maintained at about three quarters of its maximum height, in which case, the depth of flow generated by nozzle 1 would also be about three quarters of its original depth. Likewise, if bladder 45 is inflated three quarters of the way, hinged plate 41 would be lowered three quarters into the interior height of opening 37, wherein the effective height of opening 37 would be reduced to about one quarter of its maximum height, in which case, the depth of flow generated by nozzle 1 would be about one quarter of its original height as well. Accordingly, it can be seen that the depth of the water flow extruded through opening 37 can be adjusted in this manner to virtually any degree, simply by inflating or deflating bladder 45 and adjusting the position of hinged plate 41.

Injection nozzle 1 is preferably sized and shaped to produce an appropriate flow of water onto ride surface 3. The actual fixed interior height of opening 37, for example, is preferably adapted to substantially correspond with the maximum depth of flow that is desired to be created on ride surface 3. Moreover, opening 37 is preferably substantially rectangular in configuration although not necessarily so. When opening 37 is substantially rectangular in shape, as in the preferred embodiment, hinged plate 41 can also be substantially rectangular in shape. At the same time, since plate 41 is typically positioned at an angle relative to opening 37, plate 41 is preferably larger in dimension than opening 37. Preferably, the actual interior height of opening 37 can range between about 12 inches to 24 inches or more, depending on the desired performance requirements for any given application. Regardless of whether the water ride is intended to provide a relatively shallow flow or a relatively deep flow, or both, preferably, because the aperture is adjustable, the actual height of opening 37 can be made as large as necessary to accommodate the desired flow depth.

Preferably, the present invention can accommodate a variety of flow depths, such as a depth as little as 3 to 4 inches, or as deep as 24 inches or more. In either case, the effective interior height of opening 37 as determined by the adjustment features described herein is what determines the depth of flow to be propelled onto ride surface 3.

The present invention contemplates that more than one injection nozzle 1 can be provided and positioned side by side as shown in Figures 1 and 3, although not necessarily so, to create dynamic flow changes across the width of the water flow, as well as to form a relatively wide and contiguous ride surface 3. It can be seen that by adjusting the depth of flow emanating from one nozzle differently from the depth of flow emanating from another nozzle, various flow effects can be created across the width of ride surface 3. Different flow rates can also be set for each nozzle so as to create additional flow effects. Also, modular nozzle equipment 30 can be developed to incrementally enlarge the width of ride surface 3 simply by adding more nozzles 1 side by side. Placing nozzle equipment 30 as close to each other as possible will also help to ensure that the integrity and congruity of the water flow emanating from multiple injection nozzles 1 can be maintained. The Froude number is a mathematical expression that describes the ratio of the velocity of flow to the phase speed of the longest possible wave that can exist in a given depth without being destroyed by breaking. The Froude number equals the flow speed divided by the square root of the product of the acceleration of gravity and the depth of the water. The Froude number squared is a ratio between the kinetic energy of the flow and its potential energy, i.e., the Froude number squared equals the flow speed squared divided by the product of the acceleration of gravity and the water depth.

Sub-critical flow can be generally described as a slow/thick water flow. More specifically, sub-critical flows have a Froude number that is less than one, and the kinetic energy of the flow is less than its gravitational potential energy. If a stationary wave is in a sub-critical flow, then, it will be a non-breaking stationary wave. In formula notation, a flow is sub-critical when v is less than or equal to the square root of the product of g and d, where v = flow velocity in ft/sec, g = acceleration due to gravity ft/sec², and d = depth (in feet) of the sheeting body of water.

Critical flow is evidenced by wave breaking. Critical flow is where the flow's kinetic energy and gravitational potential energy are equal. Critical flow has the characteristic physical feature of the hydraulic jump itself. Because of the unstable nature of wave breaking, critical flow is difficult to maintain in an absolutely stationary state in a moving stream of water given that the speed of the wave must match the velocity of the stream to remain stationary. This is a delicate balancing act. There is a match for these exact conditions at only one point for one particular flow speed and depth. Critical flows have a Froude number equal to one. In formula notation, a flow is critical when v is equal to the square root of the product of g and d, where v = flow velocity, g = acceleration due to gravity ft/sec², and d = depth of the sheeting body of water.

Supercritical flow can be generally described as a thin/fast flow. Specifically, supercritical flows have a Froude number greater than one, and the kinetic energy of the flow is greater than its gravitational potential energy. No stationary waves are involved. The reason for the lack of waves is that neither breaking nor non-breaking waves can keep up with the flow speed because the maximum possible speed for any wave is the square root of the product of the acceleration of gravity times the water depth. Consequently, any wave which might form is quickly swept downstream. In formula notation, a flow is supercritical when v is greater the square root of the product of g and d, where v = flow velocity in ft/sec, g = acceleration due to gravity ft/sec², and d = depth (in feet) of the sheeting body of water.

A hydraulic jump is the point of wave-breaking of the fastest wave that can exist at a given depth of water. The hydraulic jump itself is actually the break point of that wave. The breaking phenomenon results from a local convergence of energy. Any wave that appears upstream of the hydraulic jump in the supercritical flow area is unable to keep up with the flow; consequently, they bleed downstream until they meet the area where the hydraulic jump occurs, wherein the flow then suddenly becomes thicker and the wave can suddenly travel faster. Thus, the convergence of waves leads to wave breaking. In terms of energy, the hydraulic jump is an energy transition point where the energy of the flow abruptly changes from kinetic to potential. A hydraulic jump occurs when the Froude number is one.

Based on the above relationships that exist between the flow speed and water depth, and how they contribute to creating different hydraulic states, it can be seen that by adjusting the depth of flow, which can be accomplished by adjusting the pressure within bladder 45, a variety of different flows and effects can be created on ride surface 3. For example, by decreasing the flow depth, a relatively thin sheet flow of water, similar to those contemplated by the previous invention, can be created on ride surface 3. And, based on the above principles, it can be seen that even without increasing flow speed (by increasing pressure using pump 33), by reducing flow depth, the flow will, nevertheless, be released at a greater speed, since by reducing the effective size of opening 37, pressure within nozzle 1 would be increased. And, when the sheet flow is shallower, and faster, the Froude number will be higher, thereby making it more likely that a supercritical sheet flow will be created and maintained.

On the other hand, by increasing flow depth, a relatively deep flow of water can be created, which can enable riders to use standard surfboards with fins when desired. And, based on the above principles, it can be seen that even without reducing flow speed (by reducing pressure using pump 33), by increasing flow depth, the flow will, nevertheless, be released at a slower velocity, since by increasing the effective size of opening 37, pressure within nozzle 1 would be reduced. And, when the flow is deeper, and slower, the Froude number will be less, thereby increasing the likelihood that a different hydraulic state, such as a hydraulic jump, or sub-critical flow, will be created. Because of these relationships between flow depth and speed, it can be seen that additional variations in flows and effects can be created by not only adjusting the flow depth (by adjusting bladder 45), but also by adjusting the flow rate, velocity and/or pressure using pump 33. In this fashion, a significantly greater variety of flow changes and hydraulic states can be produced on the same ride surface 3 using the features discussed herein. Moreover, in addition to the adjustability features incident to the flow emanating from injection nozzle 1 , additional adjustments can be employed by altering the incline or tilt of ride surface 3, such as by increasing the inclination of inclined section 15, and/or by tiling it transverse to the direction of flow, as discussed above, which can vary the pressure gradient across ride surface 3. Because a sheet flow is a volume of water that can be affected by these variables, these adjustments can help modify the flow in a manner that best suits the desired applications, wherein the flow can be made to have a length, shape, breadth, and depth sufficient to permit the type of water skimming maneuvers that are desirable for any given application.

Likewise, by having two or more adjustable nozzles 1 side by side, the flow can be adjusted so that a portion of the flow is at one depth and/or speed, and another portion of the flow is at another depth and/or speed, which can create varied effects, including a hydraulic jump on one side, and a supercritical flow on the other, even across a level ridge line. By introducing a cross-stream depth and/or speed gradient on an inclined ride surface with a level ridge line, a body of water that simulates a spilling wave with an unbroken shoulder can be produced. This "breaker like" effect can result from the flow having two coexisting hydraulic states, i.e., a shallower higher velocity supercritical flow on one side, and an adjacent deeper lower velocity flow that fails to reach the ridge line due to insufficient kinetic energy on the other side. In many cases, this slower flow will decelerate to a critical state and form a hydraulic jump below the ridge line with an associated sub-critical spill of turbulent water occurring to the side of the supercritical flow.

In the examples above, both the depth and speed of flow emanating from nozzle 1 can preferably be independently adjusted as follows: 1) both flow depth and flow speed can be increased, 2) both flow depth and flow speed can be decreased, 3) flow depth can be increased while flow speed can be decreased, and 4) flow depth can be decreased while flow speed can be increased. In this respect, virtually any combination of these kinds of changes can be used to effect a change in hydraulic state, i.e., any portion of the flow can be changed from supercritical to critical, or from critical to sub-critical, and form a hydraulic jump, as the case may be, or from sub-critical to critical, or from critical to supercritical, etc. For this reason, incorporating these additional adjustment features allows for greater and more precise control over the flow effects and changes that are produced on ride surface 3.

Moreover, independently or in combination with the nozzle adjustments discussed above, adjustments to the configuration of ride surface 3, such as adjustments to the incline or tilt of inclined section 15, can also be used to further adjust and enhance the variability of the flow effects, wherein a variety of dynamic flow changes and hydraulic states can be produced which can further enhance and add variety to the rider's experience.

By using one or more of these adjustment features, either independently, or in combination, and creating dynamic flow changes on ride surface 3, various types of flow changes and effects suitable for a variety of water skimming maneuvers can be created. For example, the location of a hydraulic jump, or where the flowing body of water changes from being supercritical to critical, or from critical to sub-critical, or other boundary layer effect, including the formation or dissipation of a hydraulic jump, or other hydraulic state, and the degree to which they occur, can be modified or shifted around on ride surface 3. Generally speaking, this can be done by coordinating one or more of the following three adjustments: 1) flow depth adjustments by adjusting bladder 45 in one or more nozzles 1 , 2) flow speed adjustments by adjusting one or more pumps 33, and 3) ride surface adjustments by adjusting one or more bladders 27 under inclined section 15 to adjust the incline or tilt of ride surface 3.

Water skimming maneuvers are those maneuvers that are capable of being performed on a flowing body of water including: riding across the face of the surface of water; riding horizontally or at an angle with the flow of water; riding down a flow of water upon an inclined surface countercurrent to the flow moving up the incline; cutting into the surface of the water so as to carve an upwardly arcing turn; riding back up along the face of the inclined surface of the body of water and cutting-back so as to return down and across the face of the body of water, etc. Water skimming maneuvers can be performed with the human body or upon or with the aid of a riding or planing vehicle such as a specialized board, or body board, or in this case, when the water is deep enough, a standard surfboard with a fin.

In order to perform water skimming maneuvers, the forward force component required to maintain a rider (including any skimming device that he or she may be riding on) in a stable riding position and overcome fluid drag is due to the down slope component of the gravity force created by the constraint of the solid flow forming surface balanced primarily by momentum transfer from the high velocity upward shooting water flow upon the ride surface. A rider's motion upslope (in excess of the kinetic energy added by the rider or vehicle) consists of the rider's drag force relative to the upward shooting water flow exceeding the down slope component of gravity. Non-equilibrium riding maneuvers such as turns, cross-slope motion and oscillating between different elevations on the "wave" surface are made possible by the interaction between these respective forces as described above and the use of the rider's kinetic energy.

In this respect, the above referenced adjustability features can create different hydraulic states or zones along ride surface 3, such as those that are in equilibrium, as well as those that are not. An equilibrium zone is that portion of an inclined riding surface upon which a rider is in equilibrium on an upwardly inclined body of water; consequently, the upslope flow of momentum as communicated to the rider and his vehicle through hydrodynamic drag can be balanced by the down slope component of gravity associated with the weight of the rider and his vehicle. The supra- equidyne zone is that portion of a riding surface contiguous with but downstream (upslope) of the equilibrium zone wherein the slope of the incline is sufficiently steep to enable a water skimming rider to overcome the drag force associated with the upwardly sheeting water flow and slide downwardly thereupon. The sub-equidyne zone is that portion of a riding surface contiguous with but upstream (down slope) of the equilibrium zone wherein the slope of the incline is insufficiently steep to enable a water skimming rider to overcome the drag force associated with the upwardly water flow and stay in equilibrium thereon. Due to fluid drag, a rider will eventually move in the direction of flow back up the incline. The adjustment features of the present invention are preferably able to cause these zones to be moved around upon ride surface 3, depending on what variables are modified, so that various flow effects can be created on different areas of the surface.

Another related advantage provided by nozzle equipment 30 of the present invention is the ability to solve the transient surge problems associated with ride start-up and rider induced flow decay. Because the flow depth can be controlled precisely, and because the speed of flow as well as whether a particular flow remains supercritical can be a function of flow depth, these adjustments preferably provide a means for self-clearing undesirable transitory surges and excess white water, which can help correct the problems associated with start-up and flow decay on ride surface 3.

Nozzle equipment 30 and the other components herein are shown as being used in conjunction with ride surface 3 for exemplary purposes only. Therefore, it can be seen that nozzle equipment 30 and its depth adjustability features and the other components discussed herein can be used in connection with virtually any sheet flow water ride application shown in previous Patent No. 5,899,633, which is incorporated herein by reference in its entirety, as well as virtually any other water ride configuration incorporating a flowing body of water as the ride surface for performing skimming maneuvers thereon.

Claims

WHAT IS CLAIMED IS:

1. A water ride capable of creating a flow of water comprising: a ride surface having at least one inclined portion; and at least one adjustable nozzle comprising an aperture through which water under pressure can pass, wherein the height of said aperture can be adjusted to adjust the depth of said flow of water emanating through said aperture and flowing onto said ride surface.

2. The water ride of claim 1 , wherein said ride surface has a down slope portion, followed downstream by a substantially horizontal portion, followed by said inclined portion.

3. The water ride of claim 1 , wherein said at least one adjustable nozzle comprises a chamber and a pump, and a bladder positioned adjacent said aperture between an upper wall portion and a lower hinged plate, wherein said bladder can be used to adjust the position of said hinged plate and therefore the height of said aperture.

4. The water ride of claim 2, wherein said at least one adjustable nozzle is adapted such that the angle of trajectory created by said nozzle onto said ride surface is substantially the same as the angle of said down slope portion of said ride surface.

5. The water ride of claim 1 , wherein adjustable nozzles are provided side by side and each of said nozzles can be independently adjusted to create varied flow effects and patterns across the width of the flow of water on said ride surface.

6. The water ride of claim 1 , wherein at least one floor bladder is provided underneath said inclined portion to adjust the height of said inclined portion relative to said ride surface.

7. The water ride of claim 6, wherein at least two floor bladders are provided underneath said inclined portion wherein by adjusting the pressure of each of said at least two floor bladders independently, the tilt of said inclined portion in a direction transverse to the flow of water can be adjusted.

8. The water ride of claim 3, wherein said pump can be used to adjust the pressure within said at least one adjustable nozzle and therefore the speed of the flow of water released by said at least one adjustable nozzle can be adjusted.

9. The water ride of claim 1 , wherein said water ride comprises an entry area located upstream from said ride surface and an exit area downstream from said ride surface, wherein said exit area comprises a grate that allows water to pass through, wherein a pool structure is provided underneath said ride surface wherein water that passes through said grate can be stored in said pool structure, and wherein water in said pool structure is available to be pumped back onto said ride surface by using said at least one adjustable nozzle.

10. A water ride capable of creating a flow of water comprising: a ride surface having at least one inclined portion; at least one adjustable nozzle comprising an aperture through which water under pressure can pass to create a flow of water emanating through said aperture and flowing onto said ride surface; and at least two floor bladders provided underneath said inclined portion wherein each of said bladders can be adjusted independently to adjust the tilt of said inclined portion relative to the travel direction of said flow of water.

11. The water ride of claim 10, wherein said ride surface has a down slope portion, followed downstream by a substantially horizontal portion, followed by said inclined portion.

12. The water ride of claim 10, wherein said at least one adjustable nozzle is adapted to adjust the height of said aperture, wherein a bladder is positioned adjacent said aperture between an upper wall portion and a lower hinged plate, wherein said bladder can be used to adjust the position of said hinged plate and therefore the height of said aperture and in turn the depth of the flow of water.

13. The water ride of claim 11 , wherein said at least one adjustable nozzle is adapted such that the angle of trajectory created by said nozzle onto said ride surface is substantially the same as the angle of said down slope portion of said ride surface.

14. The water ride of claim 10, wherein two adjustable nozzles are provided side by side and each of said nozzles can be independently adjusted to create varied flow effects and patterns across the width of the flow of water on said ride surface.

15. The water ride of claim 10, wherein a pump can be used to adjust the pressure within said at least one adjustable nozzle and therefore the speed of the flow of water released by said at least one adjustable nozzle can be adjusted.

16. The water ride of claim 10, wherein said water ride comprises an entry area located upstream from said ride surface and an exit area downstream from said ride surface, wherein said exit area comprises a grate that allows water to pass through, and wherein a pool structure is provided underneath said ride surface wherein water that passes through said grate can be stored in said pool structure, and wherein water in said pool structure is available to be pumped back onto said ride surface by using said at least one adjustable nozzle.

17. A method of varying the water flow effects of a water ride having an inclined ride surface on which a flow of water is produced, comprising: providing a ride surface having at least one inclined portion on which the water flow effects can be produced; providing at least one adjustable nozzle comprising a pump and an aperture through which water under pressure can pass, wherein the height of said aperture and therefore the depth of said flow of water emanating through said aperture and flowing onto said ride surface can be adjusted; and adjusting the height of said aperture and in turn increasing or decreasing the depth of said flow of water flowing onto said ride surface, and if necessary, adjusting the flow rate of the flow of water by adjusting said pump.

18. The method of claim 17, comprising adjusting the height of said aperture using a bladder extended between a fixed wall portion and a hinged plate of said at least one adjustable nozzle, wherein by inflating and deflating said bladder, the vertical position of said hinged plate and the height of said aperture can be adjusted.

19. The method of claim 17, comprising providing at least two adjustable nozzles side by side wherein each of said nozzles can be independently adjusted to create varied flow effects and patterns across the width of the flow of water on said ride surface.

20. The method of claim 17, comprising providing at least one floor bladder underneath said inclined portion and adjusting the height of said inclined portion by increasing or decreasing the pressure inside said floor bladder.

21. The method of claim 17, comprising providing at least two floor bladders underneath said inclined portion and adjusting the pressure of each of said floor bladders independently, wherein the tilt of said inclined portion in a direction transverse to the flow of water can be adjusted.