Abstract:
An apparatus and system for dissipating water wave energy and for shoreline control including a module with a generally hollow body, a pair of opposed flanges attached to adjacent corners of the body, a pair of axially aligned mounting apertures in the flanges for connecting the body to similar bodies for forming a wave energy dissipation system, and a recess disposed between the flanges. Each recess contains a plurality of boundary layer interrupting projections for substantially disrupting any laminar flow of water past the surface and creating turbulent flow.

Description:
FIELD OF INVENTION 
     This invention relates to devices and means by which water wave energy is reduced or dissipated to control erosion and deposition of beach sand and minimize movement of floating docking systems, and more particularly to easy to install and remove devices made from a multiplicity of modular elements. 
     BACKGROUND 
     Breakwaters, seawalls, jetties and groynes are structures intended to dissipate incoming water wave energy and to reduce or change shoreline erosion and deposition. These structures are permanent, expensive, often unsightly and have limited in effectiveness. Typically, these structures act as barriers that redirect or absorb incoming wave energy. Often this energy undermines and helps destroy these structures, or as redirected energy it continues to erode or deposit materials in other locations farther along the shoreline. 
     Various modular offshore systems utilizing tires or other elements have been introduced for purposes of erosion control, wave energy extraction, and the creation of artificial reefs to encourage the population of fish, crustacea and other aquatic life. These systems are constructed as groups that are rigidly anchored to the sea floor allowing for minimal movement. In particular, Bishop, U.S. Pat. No. 5,879,105 discloses a system of buoyant, hollow bodies, constructed to form islands in the form of inverted pyramids, rigidly anchored offshore to extract or disperse wave energy. These buoyant bodies are multi-faceted with solid protruding ends, that when connected together provide for a plurality of avenues arranged to extract the energy from the flowing water. Such an arrangement is only partially effective, having no specific design to break the laminar water flow into one of turbulence. The protruding ends make the individual bodies awkward to handle, stack and transport. 
     There is a need for a modular element that can be combined, with other elements, to form a wave energy dissipation system that has multiple recesses that will channel flowing water. When a plurality of these bodies are connected to form a wave attenuation system, the water will be channeled through a series of constrictions and voids which will dissipate the water wave energy by hydraulic resistance and friction. Critical to the effectiveness and efficiency of such a system is the need for these preferably buoyant bodies to break the laminar flow of the water into a state of turbulence. This state of turbulence increases the disorganization and chaos of the incoming water, greatly increasing the distance that individual cells of water have to travel in order to pass through the system. As these water cells have to travel farther through he system, the overall resistance to water flowing through the system is greatly increased. 
     The buoyant bodies are preferably designed so that they may be used in flotation, ballast or near neutral buoyancy situations with minimal or no modification. Any wave attenuation system constructed from these modules needs to accommodate different anchoring systems. The system must be easily movable to other locations and accommodate adjustments for buoyancy and flotation level. 
     There is also a need for the individual buoyant bodies to be easily and inexpensively manufactured. They should be light in weight, easily handled, stacked and transported. The buoyant body must be of a material that is inert and poses no threat to the environment. Further, the buoyant body and constructed wave attenuation system using a plurality of such bodies, needs to be highly versatile so that the construction of the system may be achieved in a number of different situations, e.g., a floating pontoon, the back of a boat, on the shore or even at a remote site and transported in sections to the deployment site. 
     The buoyant body should be of such a design that it may be used for other marine and near marine situations, e.g., support of floating docks, artificial reefs and beach creation devices. 
     SUMMARY OF INVENTION 
     In accordance with this invention, an apparatus and system for dissipating water wave energy and for shoreline control. Specifically it describes a wave control system including a module with a generally hollow body, a pair of opposed flanges attached to adjacent corners of the body, a pair of axially aligned mounting apertures in the flanges for connecting the body to similar bodies for forming a wave energy dissipation system, and a recess disposed between the flanges having a surface characterized by a plurality of boundary layer interrupting projections substantially disrupting any laminar flow of water past the surface and creating turbulent flow. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the detailed description of the preferred embodiment of the invention presented below, reference is made to the accompanying drawings which; 
     FIG.  1 : Perspective view of a Multi-Faceted Recessed Cubic Wave Energy Dissipation Module. 
     FIG.  2 : Top or bottom plan view of a Multi-Faceted Recessed Cubic Wave Energy Dissipation Module. 
     FIG.  3 : Front or back elevational view of a Multi-Faceted Recessed Cubic Wave Energy Dissipation Module. 
     FIG.  4 : First or second side elevational view of a Multi-Faceted Recessed Cubic Wave Energy Dissipation Module. 
     FIG.  5 : Perspective view of parts of two connected modules. 
     FIG.  6 : Exploded perspective view of three Multi-Faceted Recessed Cubic Wave Energy Dissipation Modules with connecting members and fastening devices. 
     FIG.  7 : Perspective view of a Water Wave Energy Dissipation System. 
     FIG.  8 : End-on elevational view of Water Wave Energy Dissipation System deployed with anchoring system. 
     FIG.  9 : Front elevational view of Water Wave Energy Dissipation System deployed with anchoring system. 
     FIG.  10 : End-on elevational view of Water Wave Energy Dissipation System. 
     FIG.  11 : End-on elevational view of a dock or marina using modules as flotation stabilization devices. 
     FIG.  12 : End-on elevational view of beach wall. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a perspective view of a multi-faceted cubic wave energy dissipation module  10 , hereinafter referred to as a module  10 . The module  10  is preferably constructed from low density polyethylene using a rotor mold. This mode of construction allows the module to be hollow and of uniform thickness. A module that is 24 inches cubed, is light, easily moved, stacked and transported. However, modules of other sizes may be used depending upon the intended deployed environment. 
     Referring to FIGS. 1-5, the module  10  has a top  12 , a bottom  14 , a front  16 , a back  18  a first side  20  and a second side  22 . The top  12 , bottom  14 , front  16  and back  18  are equally symmetric each having a centered rectangular projection  24 . Each rectangular projection  24  connects the first side  20  with the second side  22 . Each rectangular projection  24  is bounded by four trapezium shaped coplanar facet surfaces  26 , each equally inclined to the rectangular projections  24 . The first side  20  and second side  22  are equally symmetric, each having a centered square projection  28 . Each square projection  28  is bounded by four trapezium shaped coplanar facet surfaces  30 , each equally inclined to the square projections  28 . 
     The module  10  has recesses  32 , that are intersecting inset ribbed surfaces  34  that are inclined to, and connect the top  12  and front  16 , top  12  and back  18 , bottom  14  and front  16 , bottom  14  and back  18 . Thick connecting flanges  36  define the corners of both the first side  20 , and the second side  22 . The recesses  32  formed by the inclined, inset ribbed surfaces  34  are generally concave as shown in dotted line in FIG. 4, the ribbed surfaces themselves being formed by spaced hemi-cylinders having their longitudinal axes extending between pairs of thick connecting flanges  36 . The holes  38  connect the first side  20  and the second side  22  with the recesses  32 . Holes  30  through the thick connecting flanges  36  of the first side  20  are axially aligned to those holes  30  through the connecting flanges  36  of the second side  22 , to accept connecting members  40 . Connecting members  40  which may be rigid, such as steel rod, or flexible, such as plastic pipe or polyester cordage connect a plurality of modules  10 . A hole  42  is centered in the rectangular projection of the top  12  allowing fluid communication with the hollow inside of the module  10 . 
     FIG. 5 shows segments of two modules  10  that are rigidly connected by the connecting members  40 . The connection is held by a first fastening device  44  that fits over a short length of flexible tubing  46 , such as rubber hose. Both the first fastening device  44  such as a stainless steel hose clamp, and the flexible tubing  46  fit concentrically over the connecting member  40 , such that when the fastening device is tightened it crimps the flexible tubing  46  onto the connecting member  40 . 
     FIG. 6 demonstrates how modules  10  are joined together using the connecting members  40 , first fastening devices  44 , and flexible tubing  46 . 
     FIG. 7 is a perspective drawing of a water wave energy dissipation system  48 , hereinafter referred to as the system, constructed of a plurality of modules  10 , as may be disposed near a shoreline to dissipate water wave energy and control shoreline erosion and deposition of sand and other unconsolidated materials. 
     With reference to FIGS. 6,  7 ,  8 ,  9  and  10  the system  48  may be constructed in a continuous manner by successively joining groups of modules  10 . These joined groups of modules form repeatable units along the longitudinal axis of the system  48 . The repeatability in the construction allows the system  48  to be of any length and to be versatile to any shoreline application. Construction of the system  48  may be achieved from a platform or a boat that has dual pontoons. The system  48  may also be constructed on the water front, or at a remote location and transported in sections to the waterfront to be later deposed offshore by boat or platform. 
     The system  48  utilizes modules  10  for either buoyancy or ballast. If a module is constructed with dimensions of a 2 foot cube, then the module has an internal volume of approximately 6 cubic feet, giving the module about 360 pounds of buoyancy in fresh water. A module filled with sand alone has weight of approximately 750 pounds in fresh water. The system  48  is designed to channel water from the incoming waves into the recesses  32  of the modules  10 . As the water flows into the recesses  32  any laminar flow is broken into turbulent flow by the ribbed surfaces  34 . This flow is further broken and disturbed by the connecting member  40  that is disposed through the recesses  32 . The turbulent flow created in the recesses  32  is further channeled into voids and other recesses of other modules to extend the flow distance and maximize the hydraulic resistance and frictional loss of energy of the water wave flowing through the system  48 . An anchoring system  50  positions the system  48  near to the shoreline such that the oncoming water waves are always incident upon the same side of the system  48 . Incident water waves on the system  48  create tension in the anchoring system  50 . The anchoring system  50  stretches to accommodate this tension. The work done by the incident water wave to stretch the anchoring system  50  is converted to potential energy that is stored in the anchoring system  50  and released by conversion to kinetic energy as the anchoring system  50  pulls the system  48  back towards its neutral position against the incoming water wave. 
     FIGS. 5,  6 ,  7 ,  8 ,  9 , and  10  show construction of the system  48 , is achieved by connecting a plurality of modules  10  together using connecting members  40 . Pairs of holes  38  on one module  10  are aligned with pairs of holes  38  on a second module  52 . The connecting member  40  is disposed through the aligned holes  38 , and held rigidly by tightening the fastening device  44  that crimps the flexible tubing  46  onto the connecting member  40 . The thick connecting flange  36  of module  10  abuts the thick connecting flange  36  of module  52 . 
     A lowest level of modules  54  of the system  48  are alternately ballast and water filled. One inch steel rods are used as the connecting members  40  to join the lowest level modules  54  to a second level of modules  56 . The system  48  is constructed such that lowest level modules  54  abut pairs of a second level of modules  56 , that in turn abut a second lowest level module  54  creating a sequence alternating between the lowest level modules  54  and the second level modules  56 . The hole  42  in the second level modules  56  allows water communication between the hollow inside of the modules and that of where the system  48  is deployed. 
     A third level of modules  58  is attached to the second level of modules  56 , by disposing connecting members  40  through pairs of holes in a manner similar to the method of connecting the lowest level modules  54  to the second level modules  56 . Pairs of second level modules  56  abut groups of three of the third level modules  58 , that in turn abut pairs of second level modules  56 . The third level modules are rigidly held in place by disposing connection members  40  through aligned pairs of holes in the alternation of second level modules  56  and third level modules  58 . The connecting member  40  used to connect the second level modules  56  to the third level modules  58  is a tight weave one inch polyester cordage. An outer module  60  of the third level of modules  58  is sealed and forms a buoyant member of the system  48 . A central module  62  of the third level modules  58  is water filled through the hole  42 . 
     A fourth level of modules  64  is attached to the third level of modules  58  in a similar manner to that described above for the second level of modules  56  and the third level of modules  58 . The connecting members  40  are tight one inch weave polyester cordage. Pairs of forth level modules  64  abut the groups of three third layer modules  58 . Water may be introduced into the generally sealed pairs of the forth-level modules  64  to adjust the buoyancy and thus the flotation level of the system  48  in the water. These adjustments are made such that the outside water level is at the top of the third level of modules  58 . A top level of modules  66  is attached to the forth level of modules  64  with connecting members  40  of tight weave one inch polyester cordage, or ¾ inch schedule  80  plastic pipe. The hole  42  in the top 12 of the top level of modules  66 , may be a threaded 2 inch NTP opening to accept a flag, marine or nautical light or other accessory fitted with a 2 inch barrel fitting. The hole in the top 12 of any of the modules  10  used to construct the system may be open or sealed, depending upon the location of the module  10  in the system  48  and its purpose to be buoyant, ballast or water filled for almost neutral buoyancy. In the case of the water filled modules  10 , a second hole may be drilled in the bottom  14  to encourage the free flow of water into and out of the module  10 . 
     FIG. 10 is an end view of the system  48 . In particular, it shows portions of the connecting members  40  that are either 1 inch steel rods  68 , tight weave one inch polyester cordage  70 , or ¾ inch schedule  80  plastic pipe  72 . 
     The anchoring system  50  is attached to the system  48 , and comprises a first anchor weight  74  beneath the system resting on an ocean/lake bed  76 , a second anchor weight  78  at some distance from the system  48  in the direction of the oncoming water wave energy, and an anchor connecting cord  80 . The anchor connecting cord  80  is securely fastened at one end to the second anchor weight  78 . The anchor connecting cord  80  is threaded around the lower steel connecting member of the first level of modules  54  and a steel cleat  82  of the first anchor weight  74 . The free end of the anchor connecting cord  80  is finally threaded through holes in the first level module  154  and the middle third level module  62  to be securely fastened by a second fastening device  84 . The anchor connecting cord  80  although securely fastened at both ends, is able to freely move over the steel bar of the first level module  54  and the steel cleat  82  of the anchor weight  74 . The anchoring system  50  is duplicated in application along the longitudinal length of the system  48  and is disposed where the first level module  54  is water filled. If nylon rope is used for the anchor connecting cord  80 , it will be able to stretch as tension is exerted on it by the incoming water waves pushing against the system  48 . 
     A plurality of modules  10  may be used as a flotation and stabilization device for a floating pontoon or dock. The advantages of using modules for this application are that they are easily deployed to create a dock or marina of any length; flotation level of the dock/marina may be adjusted; the material of the modules is inert and poses no threat to the environment; because the material of the modules is inert it has a long lifetime, reducing the need to change or overhaul the deck or marina; finally, the dock or marina can remain in the water over winter as the modules are unaffected by ice. 
     FIG. 11 shows a floating dock or marina  86 , hereinafter referred to as a dock. A lowest level of dock modules  88  are attached by dock connecting members  90  to a second level of dock modules  92  in a similar manner to the construction of the system  48  as detailed above. The lowest level of dock modules  88  are alternately sand and water filled. The second level of dock modules  92  are air filled and sealed for buoyancy. Flotation level and stability are adjusted by adding water to the second level of dock modules  92 . The dock  86  is anchored by a dock anchoring system  94 . A deck  96  of the dock  86  is attached to the second level of dock modules  92  by an attaching member  98  that clamps the deck  96  to the dock connecting member  90 , used to connect groups of modules. The dock anchoring system  94  may be a single line with one end securely fastened to an anchor weight  98 , and the other end threaded through holes in the water filled lowest level dock module  88  to be securely fastened by a third fastening device  100 . The dock anchoring system  94  may be similar to the anchoring system  50  deployed with the system  48  as described above. 
     FIG. 12 is an end-on view of a plurality of modules  10  joined together to form a beach wall  102  that is partly buried in a beach or near a cliff face to enhance deposition of unconsolidated materials into wider deeper beach to create a stable shoreline environment. Such a system is key to neutralizing wave erosion and undermining of cliffs with subsequent loss of land. The versatility of the modules enables the beach wall to be built progressively higher as deposition continues. Modules are joined in a similar manner as described above for constructing the system  48 . Beach wall connecting members  104  for the wall  102  are of tight weave one inch polyester cordage. Each module  10  is filled with sand through the hole  42 . An old beach surface  106  has the wall  102  partly buried in it. A new beach surface  108  is gradually formed by deposition of unconsolidated materials, particularly during a storm when high water washes over the wall  102 . As the water ebbs back down the beach it flows through the wall  102 . The forced turbulent flow slows the water movement resulting in the deposition of any suspended material. The slope of the new beach surface  108  is closer to horizontal than the old beach surface  106 , as the partly buried wall  102  defines the slope of the new beach and stops the materials from being eroded and washed away by incoming water wave energy. As the material of the modules  10  is inert, the wall  102  can remain as a permanent structure and an integral part of the beach, possibly to be completely covered by beach material as deposition continues.