WO2006102564A2

WO2006102564A2 - Wave energy-dissipation apparatus, system and method

Info

Publication number: WO2006102564A2
Application number: PCT/US2006/010689
Authority: WO
Inventors: Yong Min Cho; Philip Yong Kim; Thomas S. Auchterlonie; Gregory P. Brummett
Original assignee: Mentor Technologies, Inc.
Priority date: 2005-03-22
Filing date: 2006-03-22
Publication date: 2006-09-28
Also published as: WO2006102564A3

Abstract

A water wave energy-dissipation apparatus (for use in a swimming pool, there being a cable strung substantially tautly between two sides of the pool) thereof includes : a support structure at least a portion of which is proximate to a median of the water surface, the support structure being connected to the cable; and a surface inclined at an acute angle relative to an imaginary horizontal plane located substantially at the median surface of the water, the inclined surface being supported by the support structure and located adjacent the water surface so as to define a substantially open region between the inclined surface and the water surface. The inclined surface has apertures, a surface area of each aperture, Aapert, being at least about two orders of magnitude smaller than a fictional total area of the inclined surface excluding apertures, Afict.

Description

WAVE ENERGY-DISSIPATION APPARATUS, SYSTEM AND METHOD

PRIORITY STATEMENT

[0001] This application claims the priority of U.S. Patent Application No.

60/663,751 (hereafter "the 751 application), filed on March 22, 2005, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

[0002] In the context of recreational and competitive swimming, it is customary to mark out swimming lanes for the swimmers. This is done by stretching lines (racing lane markers) between fixed points. In swimming pools, racing lane markers usually stretch from end to end of the pool. In larger bodies of water, racing lane markers extend over the prescribed distance between fixed locations.

[0003] Activities of a swimmer in one lane can cause conditions which are detrimental to persons performing in adjacent lanes. The progress of a swimmer along his lane is accompanied by surges and waves (wake) created by the swimmer, which fan out across adjacent lanes. The wake of a first swimmer (if unchecked) interferes with the progress of slower swimmers in adjacent lanes. The wake might also deflect the racing lane markers slightly, deforming the boundaries of the lane. This is especially a matter of considerable concern during contests, where the lead swimmer is believed to enjoy an advantage in terms of swimming through water that is relatively free of turbulence.

[0004] Racing lane markers have been developed to dampen wave action and reduce turbulence in a second lane that arises from wave action originated outside the second lane, e.g., in an adjacent first lane.

SUMMARY

[0005] An embodiment of the present invention provides a water wave energy- dissipation apparatus for use in a swimming pool, there being a cable strung substantially tautly between two sides thereof. Such an apparatus can include: a support structure at least a portion of which is proximate to a median of the water surface, the support structure being connected to the cable; and a surface inclined at an acute angle relative to an imaginary horizontal plane located substantially at the median surface of the water, the inclined surface being supported by the support structure and located adjacent the water surface so as to define a substantially open region between the inclined surface and the water surface, the surface having therein a plurality of apertures, a surface area of each

aperture, ^apert , being at least about two orders of magnitude smaller than a fictional total area of the inclined surface excluding apertures, ^m .

[0006] An embodiment of the present invention provides a wave energy- dissipation apparatus for use in a body of liquid, there being an alignment member arranged in or adjacent to the body of liquid. Such an apparatus can include: a guide member to engage the alignment member; a surface member supported by the guide member, the surface member having a wave-abating region inclined at an acute angle relative to a horizontal plane and having therein a plurality of apertures, the wave-abating region being located adjacent the liquid surface so that waves in the liquid can impinge thereon and so as to define one or more open spaces between the liquid surface and the wave-abating region.

[0007] An embodiment of the present invention provides a method of dissipating energy of waves traveling at or near a surface of a body of liquid, there being an alignment member arranged in or adjacent to the body of liquid. Such a method can include: disposing a guide member to engage the alignment member; providing a surface member having therein a plurality of apertures; supporting the surface member with the guide member; inclining a wave-abating region of the surface member at an acute angle relative to a horizontal plane; locating the wave-abating region adjacent the liquid surface so that waves in the liquid can impinge thereon and so that one or more open spaces are resultantly defined between the liquid surface and the wave-abating region.

[0008] Additional features and advantages of the present invention will be more fully apparent from the following detailed description of example embodiments, the accompanying drawings and the associated claims. BRIEF DESCRIPTION OF DRAWINGS

[0009] The accompanying drawings are intended to depict example embodiments of the present invention and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted.

[0010] Fig. 1A is a three-quarter perspective view of a wave energy dissipation apparatus according to an example embodiment of the present invention.

[0011] Fig. 1B is a three-quarter perspective view of a wave energy dissipation system according to an example embodiment of the present invention.

[0012] Fig. 2 is a side view of the wave energy dissipation apparatus according to an example embodiment of the present invention.

[0013] Fig. 3 is a side view of the wave energy dissipation apparatus according to an example embodiment of the present invention.

[0014] Fig. 4 is a side view of the wave energy dissipation apparatus according to an example embodiment of the present invention.

[0015] Fig. 5 is a simplified cross-sectional depiction of a wave being disintegrated by a wave energy-dissipation apparatus according to an example embodiment of the present invention, e.g., that of Figs. 1A, 1B, 2-4 and 7A-8.

[0016] Figs. 6A-6D depict annotated still images taken from a video entitled

"Platform#1 , Wave-Cut & Boats_3.4Meg.avi" found in the 751 application that shows a model of a wave energy dissipation system related to the present invention.

[0017] Fig. 7A is a top view of a wave energy dissipation system according to an example embodiment of the present invention.

[0018] Fig. 7B is a top view of a wave energy dissipation system according to an example embodiment of the present invention.

[0019] Fig. 8 is a top view of a wave energy dissipation system according to an example embodiment of the present invention.

[0020] Fig. 9 is a three-quarter perspective view of a wave energy dissipation apparatus and system according to an example embodiment of the present invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

[0021] It will be understood that if an element or layer is referred to as being "on,"

"against," "connected to" or "coupled to" another element or layer, then it can be directly on, against connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, if an element is referred to as being "directly on", "directly connected to" or "directly coupled to" another element or layer, then there are no intervening elements or layers present. Like numbers refer to like elements throughout. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

[0022] Spatially relative terms, such as "beneath", "below", "lower", "above",

"upper" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" the other elements or features. Thus, term such as "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0023] Although the terms first, second, etc. may be used herein to describe various elements, components, regions, layers and/or sections, it should be understood that these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are used only to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present invention.

[0024] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "includes" and/or "including", when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

[0025] Fig. 1A is a three-quarter perspective view of a wave energy dissipation apparatus 100 according to an example embodiment of the present invention.

[0026] Fig. 1B is a three-quarter perspective view of a wave energy dissipation system 150 according to an example embodiment of the present invention. [0027] In Fig. 1A, the wave energy-dissipation apparatus includes: a guide member 102 to engage (e.g., slidably and/or rotatably) an alignment member 104 (e.g., a cable on which are otherwise strung racing lane markers according to the Background Art) arranged in or adjacent to the body of liquid 106; and a surface member 108 supported by the guide member 102. The surface member 108 (e.g., three-flat substantially flat panels joined together and having a triangular cross-section) has wave-abating regions 110A, 110B and 110C (in Figs. 1A-1B, e.g., each wave-abating region corresponds to substantially the entirety of the corresponding flat panel). As depicted in Fig. 1A, two of the wave-abating regions 110A and 110C are inclined at an acute angle relative to a horizontal plane, while the third wave-abating region 110B is substantially parallel to the horizontal plane.

[0028] The wave-abating region 110 is apertured, i.e., it has a plurality of apertures 112. Typically, the liquid 106 in which the wave energy-dissipation apparatus 100 is disposed has water as a majority component and the body of liquid is a swimming pool or natatorium. Other liquid compositions, however, are contemplated. And other bodies of liquid are contemplated, e.g., a lake, the seashore, a chemical process tank, a nautical modeling tank, a river, a canal, a harbor, etc.

[0029] As depicted in Fig. 1B, the upper wave-abating regions 110A and 110C are located adjacent the liquid surface 114 so that waves in the liquid can impinge thereon. Further, the wave-abating regions 110 are arranged so as to define one or more open spaces 116 between the liquid surface 114 and the wave-abating region 110.

[0030] The guide member 102 is depicted in Figs. 1A-1B as a cylindrical annulus that can span a length of the wave energy-dissipation apparatus 100. Alternatively, e.g., there can be a plurality of such guide members 102 distributed along the longitudinal axis of the wave energy-dissipation apparatus 100. The surface member 108 can be supported by the guide member 102 via webs 118 and/or spokes. The alignment member 104 can pass through a hole 120 in the guide member 102. Fig. 1B can be described as depicting a plurality of the wave energy-dissipation apparatuses 100 (or segments or units) strung along an alignment member 104.

[0031] In Figs. 1A-1B, the wave-abating regions 110 do not intersect a longitudinal axis of the alignment member 104. Alternatively, other embodiments are configured so that the wave-abating region(s) 110 do intersect the longitudinal axis of the alignment member 104.

[0032] Examples of the alignment member 104 include: a cable; a rope; a rod; a rod-like structure; a plurality of interlocking structures that approximate one of a cable and a rod-like structure; and the like. Such an alignment member 104 can, but does not necessarily have to, lie within the horizontal plane.

[0033] Again, apertures 112 (having any shape, e.g., circles, ellipses, polygons, j\ etc.) are formed in the wave-abating regions. An area of each aperture 112, ^apert , of an instance (e.g., 110A) of the wave-abating region 110 is at least about two orders of magnitude smaller than a fictional total area of the instance 110A of the wave-abating region

A A

110 excluding apertures, ^fict . As an example, the area of each aperture 112, ^aperi , of the instance 110A of the wave-abating region 110 can be at least about three orders of

Δ magnitude smaller than ^m .

[0034] The ratio of the total area of the plurality of apertures 112, ^ ^apeft^^ to

Δ the fictional total area ^m of an instance of wave-abating region 110 should be sufficient for the plurality of apertures 112 to disintegrate the wave. But there also should remain a sufficient amount of non-aperture area on the instance of the wave-abating region 110 such that the wave does not pass through the instance of the wave-abating region 110

A (i) substantially intact. To enhance such wave disintegration, the magnitudes of ^apert ' should be selected such that the ratio is achieved via a greater number rather than a lesser number of apertures. More particularly, a ratio of the total area of the plurality of apertures,

2_v ^aper^t \ ) _{t0 tne} fictional total area ^m of the instance of the wave-abating region 110 can

∞ 30% < ^ ^apert <^ 50% .

Δ be in a range ^r'^ct

[0035] Fig. 2 is a side view of the wave energy dissipation apparatus 200 according to an example embodiment of the present invention.

[0036] In Fig. 2, it is assumed that two alignment members 204, e.g., cables, are provided. Typically, such cables 204 will be tensioned so as to be substantially coplanar. A clamp body 222+224 having an upper and lower portion 222 and 224 (e.g., half) can be provided as the guide member through which pass the alignment members 204. The upper and lower halves 222 and 224 of the clamp body 222+224 can be held together with a fastener 226, e.g., a nut & bolt assembly, etc.

[0037] A support member 228 can be provided at the left and right sides of the clamp body 222+224 and mounted thereto in some manner, e.g., engaged in a void formed by the upper and lower halves 222 and 224 of the clamp body when clamped together, etc. To each support member 228 can be connected a frame 230 which itself supports a surface member 232 having the wave-abating region formed therein. For example, the frame 230 can be pivotably mounted (e.g., via a compressive fastener 234 such as a nut & bolt assembly) to the support structure 228 so that the angle of the surface member 232 relative to a horizontal plane 236 (ideal median liquid surface) is adjustable.

[0038] When tensioned as such, the pair of cables 204 resist rotation of the clamp body 222+224 about an axis parallel to the cables 204 and coplanar therewith. This facilitates a stable inclination of the wave-abating regions on the apertured surface members 232 with respect to a median surface 236 of the liquid 238.

[0039] Fig. 3 is a side view of the wave energy dissipation apparatus 300 according to an example embodiment of the present invention.

[0040] Fig. 4 is a side view of the wave energy dissipation apparatus 400 according to an example embodiment of the present invention.

[0041] In Figs. 3-4, the cross-section of the wave energy-dissipation apparatus

300/400 is taken perpendicular to a longitudinal axis of the alignment member 304, with the result that the surface member resembles one of the following: a caret (^Λ) 340, as in Fig. 3; and a diamond 342 (0) as in Fig. 4. Alternatively, the cross-section could resemble a non- diamond polygon; and a deformed polygon having at least one curved face. Further in the alternative, the cross-section can resemble, e.g., one of the following: a greater-than symbol (>); a deformed polygon having at least one curved face; etc.

[0042] In Figs. 3-4, four guide members 340A-340D and four corresponding alignment members 304 (e.g., cables) are depicted. When tensioned, the alignment members 304 resist rotation of wave energy-dissipation apparatus 300/400 about an axis parallel to the cables 304 and located therebetween. Again, this facilitates a stable inclination of the wave-abating regions on the surface members 340/342 with respect to an ideal median surface 344 of the liquid 346. For example, two (or, for that matter, one) of the guide members (and the corresponding two alignment members) are optional. In Fig. 3, the upper two guide members 340A and 340B have been indicated as optional. In Fig. 4, the upper left guide member 340A and the lower right guide member 340C have been indicated as optional. Other arrangements of optional guide members are contemplated.

[0043] A further advantage of Fig. 4, without being bound by theory, can be a follows. To the extent that a portion of a wave impinging upon the wave energy-dissipation apparatus is propagating beneath the water surface, it might impinge upon a lower wave- abating region (as contrasted to an upper wave-abating region a portion of which rises above the median water surface). The space internal to the wave energy-dissipation apparatus that is adjacent the lower wave-abating region is filled with water. Hence, less (if any) wave-disintegration will be caused by the lower wave-abating region relative to what is caused by the upper wave-abating region. But the lower wave-abating region will reflect a wave propagating in the horizontal direction downward into the pool. As such, this can help reduce turbulence at the surface of the water.

[0044] Operation of a wave energy-dissipation apparatus, and system, will now be discussed in terms of Fig. 5, where Fig. 5 is a simplified cross-sectional depiction of a wave being disintegrated by a wave energy-dissipation apparatus according to any one of the example embodiments of the present invention.

[0045] Without being bound by theory, it is believed that the following explains how the apparatus of Figs. 1A-4 and 7A-9 dissipate the energy of a wave propagating in liquid.

[0046] In Fig. 5, a wave is represented as stratified, i.e., is represented as a group of wave-strata. Each wave stratum is akin to a growth-ring of a tree or an annulus (albeit not circular, rather sinusoidal). The wave-strata have at least substantially the same frequency (if not the same) and are at least substantially in phase (if not totally so), albeit of different amplitude ranges. The group of wave-strata is depicted as impinging upon an apertured wave-abating region of a surface member, e.g., such as in Figs. 1A-4. Each wave-stratum impinges upon the wave-abating region at a different elevation. As such, each wave-stratum encounters a different set of (horizontally-distributed) apertures in the wave-abating region. Each wave-stratum has both a horizontal and vertical component of velocity. Each such set of apertures acts upon the corresponding wave-stratum to change at least a substantial fraction of its velocity from being manifested by the horizontal component to being manifested by the vertical component, more specifically the downward vertical component.

[0047] Figs. 6A-6D depict annotated still images taken from a video entitled

"Platform#1 , Wave-Cut & Boats_3.4Meg.avi" found in the 751 application that shows a model 600 of a wave energy dissipation system related to the present invention.

[0048] In Figs. 6A-6D, a source (not depicted) of waves is positioned at the right- hand side. When viewed in the sequence, Figs. 6A-6D suggest how the wave energy- dissipation system 606 depicted therein disintegrates waves that impinge upon it.

[0049] In Fig. 6A, the model 600 includes: a tank 602 having a grid 604 printed on a back wall to introduce scale; a wave energy-dissipation system 606 (including a surface member having an inclined & apertured wave-abating region, and a frame 607 to support the surface member); a floating support structure 608; a boat 610 disposed between the wave energy-dissipation system 606 and waves 612 propagating towards the same such that the boat is unprotected from the waves; another boat disposed behind such waves so as to be shielded from the same by the wave energy-dissipation system 606; calm water resulting from the shielding effect of the wave energy-dissipation system 606; and a median water surface 618. Also depicted is a wave 612'" impinging on the wave abating region of the wave energy-dissipation system 606. In general, waves propagate from right to left in Figs. 6A-6D.

[0050] In Fig. 6B, the unprotected boat is sitting on a crest of an incoming wave

612' (located to the left of where wave 612 was located). In Fig. 6C, the unprotected boat 610 is slipping the backside of the wave towards the trough that trails the crest of incoming wave 612" (located to the left of where wave 612' was located). In Fig. 6D, the unprotected boat 610 is fully in the trough trailing the crest of now impinging (on the wave abating region of the wave energy-dissipation system 606) wave 612'".

[0051] In each of Figs. 6A-6D, the unprotected boat 610 is subjected to substantial buffeting by waves 612, 612', 612" and 612'". In contrast, in each of Figs. 6A-6D, the water 616 behind the wave energy-dissipation system 606 can be described as calm such that the protected boat 614 experiences substantially no buffeting relative to what is suffered by the unprotected boat 610.

[0052] The protected side (the left side) of the wave energy-dissipation system

606 exhibits substantially the same water surface level (substantially the median water surface 618) irrespective of the waves that impinge upon the system 606. This is due to the system 606 dissipating enough of the energy of impinging wave 612'" so that there is little effect upon the protected boat 614 if (and when) the remainder of the impinging wave 612"'reaches the protected side (the calm water 616). In contrast, the unprotected side (the right side) of the system 606 manifests a widely varying water surface level due to the incoming waves (612, 612', 612").

[0053] Details of the model 600 depicted in the videos found in the 751 application entitled "Platform#1 , Wave-Cut & Boats_3.4Meg.avi" and "Platform#1 , Wave-Cut & Boats_12.9Meg.avi" (which, again, are but examples of a wave energy-dissipation apparatus related to the present invention and thus should not be viewed as limiting) are as follows.

[0054] The wave energy-dissipation system depicted in FIGS. 6A-6D can be described as one-sided in the sense of being arranged to dissipate the energy of waves that impinge thereon only from one side (here, the right). Embodiments of the present invention can be one-sided as such. But they can also be two-sided in the sense of being arranged to dissipate the energy of waves that impinge thereon only from opposite sides (e.g., the left and right sides). As the reader will recognize, the example embodiments discussed relative to Figs. 1A-4 and 7A-9 are two-sided. In a circumstance in which the wave energy- dissipation apparatus and systems including such are used to demarcate racing lanes in a swimming pool, typically a two-sided implementation will be adopted.

[0055] Fig. 9 is a three-quarter perspective view of a wave energy dissipation apparatus 902 and system 900 according to an example embodiment of the present invention.

[0056] In Fig. 9, the surface member 960 of the wave energy-dissipation apparatus 902 (that has apertured wave-abating regions) is a tetrahedron. Internal to the tetrahedron are one or more spaces that are open from the wave-abating region down to where an ideal median surface of the liquid 962 would be located. Alternatively, the surface member 960 can be configured as some other type of polyhedron. While depicted, for simplicity, in Fig. 9 as being substantially planar (if not planar), the wave-abating region can represent one or more faces of a deformed polyhedron (e.g., having at least one curved face), one or more portions of a surface of revolution, etc. By stringing two of the wave energy-dissipation apparatuses 902 of Fig. 9 together on an alignment member 904, a wave energy-dissipation system 900 is achieved.

[0057] Fig. 7A is a top view of a wave energy dissipation system 700 according to an example embodiment of the present invention.

[0058] In Fig. 7A, a plurality of tetrahedral wave energy-dissipation apparatuses

702, e.g., as in Fig. 9, are provided, which from the top view appear as diamond-shaped. Whereas in Fig. 9, the guide member (not depicted) passes the alignment member 704 substantially through a central axis, the guide members (not depicted) of the wave energy- dissipation apparatuses 702 of Fig. 7A are asymmetrically disposed such that a string of such apparatuses 702 (or, in other words, the system 700 of Fig. 7) appears staggered. Between any two such apparatuses 702, a spacer member 703 (e.g., that is discrete) is provided through which passes the alignment member 704. The spacer members 703 resemble parallelograms from a top view and can be, e.g., circular in cross-section.

[0059] Fig. 7B is a top view of a wave energy dissipation system 700' according to an example embodiment of the present invention.

[0060] Like Fig. 7A, Fig. 7B depicts a system of staggered wave energy- dissipation apparatuses 702. In contrast to Fig. 7A, less overlap is depicted in Fig. 7B between any two parallel sides of corresponding apparatuses 702.

[0061] Fig. 8 is a top view of a wave energy dissipation system 800 according to an example embodiment of the present invention.

[0062] In Fig. 8, the overall visual sawtooth impression of Figs. 7A-7B is retained, albeit achieved via a plurality of hour-glass-shaped wave energy-dissipation apparatuses 802. The hour-glass-shaped apparatus 802 can be symmetrical with respect to the longitudinal axis. It can also be asymmetric with respect to the bottleneck. More particularly, one end can be convex 870 and the other can be concave 872. If such ends adopt complimentary arcs, then a string of such wave energy-dissipation apparatuses can nest together so as to reduce a window between any two thereof through which a wave could pass substantially intact.

[0063] In general as to Figs. 1A-4 and 7A-9, the wave-abating regions are inclined at an acute angle relative to a horizontal plane and are arranged so that waves in the liquid would impinge on them. The angle at which the wave-abating regions is inclined, relative to the horizontal plane, can be in a range ~ — " ^eincime — ^ ^{0 ■} Typically, the wave- abating region will be arranged so that a majority of waves in the liquid impinge upon the

wave-abating region in a range of angles ^{~ a} "w^mge —

[0064] Again, apertures (having any shape, e.g., circles, ellipses, polygons, etc.) are formed in the wave-abating regions of Figs. 1A-4 and 7A-9. An area of each aperture,

/\ ^apert , of the wave-abating region is at least about two orders of magnitude smaller than a

Λ fictional total area of the wave-abating region excluding apertures, ^fict . As an example, the

area of each aperture, ^apert , of the wave-abating region can be at least about three orders

Λ of magnitude smaller than ^m .

[0065] The ratio of the total area of the plurality of apertures, λ^^^peΛ¹) _{to the} fictional total area ^m in Figs. 1A-4 and 7A-9 should be sufficient for the plurality of apertures to disintegrate the wave. But there also should remain a sufficient amount of non- aperture area on the wave-abating region such that the wave does not pass through the wave-abating region substantially intact. To enhance such wave disintegration, the

A U) magnitudes of ^{apert V} ' should be selected such that the ratio is achieved via a greater number rather than a lesser number of apertures. More particularly, a ratio of the total area

of the plurality of apertures,

_to the fictional total area ^m can be in a range

₃₀O_{/o <} ∑Λpert(0 _<ta 5_| 0%

Afcrf

[0066] It is assumed, e.g., in Figs. 1A-4 and 7A-9 that about 30% of the wave- abating region (or the upper wave-abating region if a lower counterpart is also present) can be disposed below the median of the liquid surface.

[0067] As an alternative, the wave-abating regions of Figs. 1A-4 and 7A-9 can be described as including a plurality of portions. A given such portion can be described by an aperture: non-aperture ratio, namely a ratio of the total area of the plurality of apertures in the

given portion, E^⁰L iport/i,on to a fictional total area thereof excluding apertures A n^et i^po^rtioⁿ _ |_{n sucn an} alternative, the wave-abating region can exhibit a gradient of such ratios.

[0068] As an example of a gradient of aperture:non-aperture ratios, suppose that the wave-abating region is divided into three portions, namely a lower portion (partially disposed below median liquid surface), a middle portion and an upper portion (disposed farthest) away/above the median liquid surface). In this example, the gradient of ratios could relate as follows.

∑A_Pert(i) < ∑ApeΛQ < ∑ApertiO

Vfcf 69] lower A 'fict middle A

[00 Hid upper

[0070] Such a gradient might better accommodate a variety of wave amplitudes, e.g., the lower portion might be better suited to waves of smaller amplitudes, the middle portion might be better suited to waves of medium amplitudes, and the upper portion might be better suited to waves of larger amplitudes.

[0071] Optionally, floatation members (not depicted) can be provided on any of the wave energy-attenuation apparatus mentioned above, e.g., on the guide member, the surface member and/or the webs/spokes. Alternatively, the guide member, surface member and/or webs/spokes can be made of a material that is sufficient less dense than the liquid so that it floats.

[0072] For simplicity, Figs. 1A-4 and 7A-9 have been depicted with sharp corners

(e.g., triangular points). As a practical matter, such corners would likely be rounded to reduce the risk of injury upon the occasion of a collision between a swimmer's appendage and the wave energy-dissipation apparatus.

[0073] Though other methods are manufacture are contemplated, it is anticipated that injection molding will typically be used to manufacture the wave energy-dissipation apparatuses of Figs. 1A-4 and 7A-9.

[0074] With some example embodiments of the present invention having thus been described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications are intended to be included within the scope of the present invention.

Claims

CLAIMSWhat is Claimed:

1. A water wave energy-dissipation apparatus for use in a swimming pool, there being a cable strung substantially tautly between two sides thereof, the apparatus comprising: a support structure at least a portion of which is proximate to a median of the water surface, the support structure being connected to the cable; and a surface inclined at an acute angle relative to an imaginary horizontal plane located substantially at the median surface of the water, the inclined surface being supported by the support structure and located adjacent the water surface so as to define a substantially open region between the inclined surface and the water surface, the surface having therein a plurality of apertures, a surface area of each aperture, A_gpert , being at least about two orders of magnitude smaller than a fictional total area of the inclined surface excluding apertures, A_fict .

2. The apparatus of claim 1 , wherein the area of each aperture is at least about three orders of magnitude smaller than a fictional total area of the inclined place excluding apertures.

3. The apparatus of claim 1 , wherein a ratio of the total area of the plurality of apertures, ^P>4_aperf (/) to the fictional total area A_fict is sufficient for the plurality of apertures to disintegrate the wave and yet for there to remain a sufficient amount of non-aperture area on the inclined surface such that the wave does not pass through the inclined surface substantially intact.

4. The apparatus of claim 3, wherein magnitudes of A_apert(i) are selected such that the ratio is achieved via a greater number rather than a lesser number of apertures.

5. The apparatus of claim 4, wherein a ratio of the total area of the plurality of apertures, ∑A_aper_t(') ^{to tne} fictional total area A_m is in a range

∞ 30% < ^ ^apert <∞ 50% .

Afjct

6. The apparatus of claim 1 , wherein about 30% of the inclined surface is disposed below the median of the water surface.

7. The apparatus of claim 1 , wherein the inclined surface is inclined at an angle, relative to the propagation direction, in a range « 15° < angle <∞ 45° .

8. The apparatus of claim 1 , wherein each of the plurality of apertures is a circle.

9. The apparatus of claim 1 , wherein: the inclined surface includes a plurality of portions; each portion can be described by a ratio of the total area of the plurality of apertures therein, _> *° ^a fictional total area thereof excluding apertures [A_rιct] _oΛtøn ;

and the inclined surface exhibits a gradient of such ratios.

10. The apparatus of claim 1 , wherein the inclined surface is substantially planar.

11. The apparatus of claim 1 , wherein the inclined surface is pivotably mounted to the support structure such that the angle thereof relative to the propagation direction is adjustable.

12. The apparatus of claim 1 , wherein inclined surface is a plate supported underneath by a trussed arrangement.

13. The apparatus of claim 1 , wherein: the support structure is formed so that the cable passes therethrough.

14. A wave energy-dissipation apparatus for use in a body of liquid, there being an alignment member arranged in or adjacent to the body of liquid, the apparatus comprising: a guide member to engage the alignment member; and a surface member supported by the guide member, the surface member having a wave-abating region inclined at an acute angle relative to a horizontal plane and having therein a plurality of apertures, the wave-abating region being located adjacent the liquid surface so that waves in the liquid can impinge thereon and so as to define one or more open spaces between the liquid surface and the wave-abating region.

15. The apparatus of claim 14, wherein the wave-abating region does not intersect a longitudinal axis of the alignment member.

16. The apparatus of claim 14, wherein the wave-abating region does intersect a longitudinal axis of the alignment member.

17. The apparatus of any of claims 14, wherein an area of each aperture, A_apert , of the wave-abating region is at least about two orders of magnitude smaller than a fictional total area of the active region excluding apertures, A_fict .

18. The apparatus of claim 17, wherein the area of each aperture is at least about three orders of magnitude smaller than a fictional total area of the inclined place excluding apertures.

19. The apparatus of claim 14, wherein the alignment member is one of the following: a cable; a rope; a rod; a rod-like structure; a plurality of interlocking structures that approximate one of a cable and a rod-like structure; and a sidewall of a swimming pool in a circumstance in which the body of liquid is the swimming pool.

20. The apparatus of claim 19, wherein the alignment member lies within the horizontal plane.

21. The apparatus of claim 14, wherein the wave-abating region represents one or more faces of one of the following, a polyhedron; and a deformed polyhedron having at least one curved face.

22. The apparatus of claim 14, wherein the wave-abating region represents one or more portions of a surface of revolution.

23. The apparatus of claim 14, wherein the wave-abating region is at least substantially planar.

24. The apparatus of claim 17, wherein a ratio of the total area of the plurality of apertures, ]TM_apert (/) to the fictional total area A_m is sufficient for the plurality of apertures to disintegrate the wave and yet for there to remain a sufficient amount of non-aperture area £>n the wave-abating region such that the wave does not pass through the wave-abating region substantially intact.

25. The apparatus of claim 11241 , wherein magnitudes of A_gpert(i) are selected such that the ratio is achieved via a greater number rather than a lesser number of apertures.

26. The apparatus of claim 17, wherein a ratio of the total area of the plurality of apertures, ]P A,_pert(/) to the fictional total area A_fict is in a range

∞ 30% < ^ ^apert <w 50% .

Afict

27. The apparatus of claim 14, wherein about 30% of the wave-abating region is disposed below the median of the liquid surface.

28. The apparatus of claim 14, wherein the angle at which the wave-abating region is inclined, relative to the horizontal plane, is in a range FH 15° < angle <« 45° .

29. The apparatus of claim 14, wherein each of the plurality of apertures is a circle.

30. The apparatus of claim 14, wherein: the wave-abating region includes a plurality of portions; each of the plurality of portions can be described by a ratio of the total area of the plurality of apertures therein, []PA,_perf(/)] , to a fictional total area thereof excluding

apertures [>V ^ ; and the wave-abating region exhibits a gradient of such ratios.

31. The apparatus of claim 14, wherein, in cross-section of the apparatus taken perpendicular to a longitudinal axis of the alignment member, the surface member resembles one of the following: a caret (^Λ); a diamond (0); a non-diamond polygon; and a deformed polygon having at least one curved face.

32. The apparatus of claim 14, wherein: the guide member is formed so that the alignment member passes therethrough.

33. The apparatus of claim 14, wherein the wave-abating region is arranged with respect to the alignment member so that a majority of waves in the liquid impinge upon the wave- abating region in a range of angles pa 30° < angle <∞ 150° .

34. The apparatus of claim 14, wherein the apparatus is formed of a polymer and is of injection-molded construction.

35. The apparatus of claim 34, wherein the apparatus is monolithic.

36. A method of dissipating energy of waves traveling at or near a surface of a body of liquid, there being an alignment member arranged in or adjacent to the body of liquid, the method comprising: disposing a guide member to engage the alignment member; providing a surface member having therein a plurality of apertures; supporting the surface member with the guide member; inclining a wave-abating region of the surface member at an acute angle relative to a horizontal plane; locating the wave-abating region adjacent the liquid surface so that waves in the liquid can impinge thereon and so that one or more open spaces are resultantly defined between the liquid surface and the wave-abating region.

37. The method of claim 36, further comprising: disposing the wave-abating region so as not to intersect a longitudinal axis of the alignment member.

38. The method of claim 36, further comprising: disposing the wave-abating region also to be inclined at an acute angle with respect to the alignment member.

39. The method of claim 36, further comprising: configuring the wave-abating region so that a ratio of the total area of the plurality of apertures, ^A,_perf(/) *° ^a fictional total area A_fict is sufficient for the plurality of apertures to disintegrate the wave and yet for there to remain a sufficient amount of non-aperture area on the wave-abating region such that the wave does not pass through the wave-abating region substantially intact.

40. The method of claim 39, wherein the step of configuring includes selecting magnitudes of A_gpert(i) such that the ratio is achieved via a greater number rather than a lesser number of apertures.

41. The method of claim 36, wherein the step of configuring includes selecting a ratio of the total area of the plurality of apertures, ∑A_apert(i) to the fictional total area A_m is in a range

42. The method of claim 36, further comprising: disposing about 30% of the wave-abating region below a median of the liquid surface.

43. The method of claim 36, wherein the step of inclining sets the angle of inclination of the wave-abating region, relative to the horizontal plane, in a range PH 15° < angle <FH 45° .

44. The method of claim 36, further comprising: setting the plurality of apertures to be circles.

45. The method of claim 37, wherein: the wave-abating region includes a plurality of portions; each of the plurality of portions can be described by a ratio of the total area of the plurality of apertures therein, [^A,_perf(/^')l , to a fictional total area thereof excluding

ap ^rertures [ LA n,e.,t i Ipor _αti.on ; and the method further comprises the following, configuring the wave-abating region to exhibit a gradient of such ratios.