Patent Description:
Water collection systems are typically used to provide water to end users such as manufacturing plants, cities, irrigation systems, and power generation facilities located adjacent a body of water such as a river, lake, or salt water bodies. The end users may employ this type of system as an alternative to drilling water wells or buying water directly from a municipal source. Additionally, use of these systems may be determined by the location of the end user, for example remote locations where water from a municipal source and/or electrical power to operate pumps is not readily available. These water collection systems are advantageous in that they can be operated efficiently and economically with an ability to adapt to varying water and environmental conditions.

Conventional water collection systems typically use an inlet pipe that is adapted to transport water from a position submerged in a body of water to an end user located adjacent to or proximate the body of water. An inlet pipe is generally submerged in the body of water and the end of the inlet pipe is typically coupled to an intake screen assembly that defines one or more filtering members. One common intake screen configuration is a Tee-style configuration having two filtering screens on opposing ends. A typical construction for large intake screen assemblies is a flanged tee section with two screen cylinders that are cantilevered from opposite ends of the tee section, and with solid closures such as flat plates, cones, or dished heads on the distal ends of each screen cylinder. These closures can be removable, or include access portals within their design. The separate components of the assemblies are usually welded together.

Regardless of the specific configuration, the screen intakes are generally configured to prevent waterborne debris of a certain size, from entering the inlet pipe. At the same time, the screen intakes must be designed to protect aquatic life while filtering debris along the length of the intake screen surfaces. To do this, the flow velocity through the screens should be kept below a maximum peal level, which may be about <NUM> f/s or other limits that are defined by local requirements and/or specifications. One way to reduce the flow resistance and control screen intakes must be designed to protect aquatic life while filtering debris along the length of the intake screen surfaces. To do this, the flow velocity through the screens should be kept below a maximum peal level, which may be about <NUM> f/s or other limits that are defined by local requirements and/or specifications. One way to reduce the flow resistance and control the flow velocity at the screen's surface is to use flow modifiers inside the screen intake. For example, the Johnson Screens® brand of screen intakes improves flow uniformity across the filtering screens using flow modifiers as disclosed in <CIT> and <CIT>.

In addition to designs that are optimized for flow performance, screen intake design must also take into account external forces such as, for example, environmental conditions such as ice formation as well as potential impact loads when the screen intakes are located at their submerged collection locations. As such, it would be advantages to improve upon conventional screen intake designs so as to not only increase flow performance within and across a screen intake but to also increase the structural strength of the screen intake so as to better resist external pressures and impact loads.

<CIT> describes a strainer for use with a washing machine in the form of an elongate perforated shell.

<CIT> describes a float portion, a drain head portion, and an outlet pipe portion which are sequentially connected.

<CIT> describes a screen configuration provided for the extraction of wastewater from a wastewater reactor, while precluding the entry of biological support media.

<CIT> describes a T-shaped filter or screen with a vertical stem section set over a container outlet, and a horizontal section on top of the vertical section, each portion being of cross-section obviating flat particle-collecting areas.

<CIT> describes a screen intake apparatus for a water intake system uses a cleaning system to clean one or more screen intakes.

The invention to which this European patent relates is defined in the appended claims. Embodiments disclosed herein include a screen intake assembly having a central manifold for the attachment of individual screen portions and internal flow modifiers. In some embodiments, the central manifold can include a central screen portions such that an entire intake assembly length includes an external screen for increasing a fluid intake capacity of the screen intake assembly. The screen intake assembly can comprise individual screen sections that are selectively attached to the central manifold such that the fluid intake capacity of the screen intake assembly can be selectively adjusted. In some embodiments, the screen sections and central manifold can be adjacently assembled utilizing an external connection, such as, for example, an external flange wall to facilitate assembly at point of use. In some embodiments, the internal flow modifiers can be operably coupled to the central manifold to selectively influence fluid flow characteristics within the screen intake assembly. The internal flow modifiers can be comprised of individual flow modifier sections that allow the internal flow modifier to be expanded to accommodate the number of screen portions attached to the central manifold.

In general, the embodiments of the present invention can comprise an adjustable or expandable screen intake assembly that can utilize a central manifold screen section, individual screen sections, a central flow modifier and individual flow modifier sections to adjust fluid intake characteristics including, for example, flow capacity, pressure drop, screen utilization, and the avoidance of turbulent flow conditions within the screen intake assembly. In addition, screen intake assemblies of the preset invention can include integral cleaning assemblies that serve to remove particulates and biofouling.

Subject matter hereof may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying figures. <FIG> and <FIG> are provided for illustrative purposes to provide background for disclosed embodiments falling within the scope of the appended claims.

<FIG> illustrates a conventional intake screen assembly <NUM> of the prior art. An intake screen assembly <NUM> can generally comprise an intake member or other body shown in the form of a central, flanged tee-section <NUM>, one or more closure members shown as end plates 20a, 20b, a center manifold <NUM>, a lower portion <NUM>, one or more screen portions 106a, 106b, and one or more manifold walls 108a, 108b. In embodiments, the approximate center of screen intake assembly <NUM> is shown along axis A. Center manifold <NUM> extends substantially and continually from axis A to manifold wall 108a and 108b, and is comprised of a material that does not allow fluid intake or inflow, such as stainless steel or copper-nickel pipe or tubing. Screen portions 106a, 106b each have a corresponding screen length 110a, 110b that is defined between the respective manifold wall 108a, 108b to the respective end plate 20a, 20b. Screen portions 106a, 106b can each comprise approximately one-third of the total length of screen intake assembly <NUM>. Screen intake assembly <NUM> can also comprise flow modifiers, various embodiments of which are disclosed herein.

As seen in <FIG>, a screen intake assembly <NUM> can substantially resemble an overall shape of screen intake assembly <NUM> but wherein the central manifold <NUM> has been replaced with a central portion <NUM> including screen elements to increase the available filtering area, filtering capacity, flow uniformity and efficiency. Screen intake assembly <NUM> comprises an intake member or other body shown in the form of a central, flanged tee-section <NUM>, a pair of closure members shown as end plates 212a, 212b, the central portion <NUM>, a lower portion <NUM>, screen portions 206a, 206b, and one or more manifold walls 208a, 208b. In embodiments, manifold wall 208a, 208b is positioned at the approximate center of screen intake assembly <NUM>, which is shown along axis A. Each screen portion 206a, 206b has a screen length 210a, 210b defined between the corresponding manifold wall 208a, 208b, or manifold side when only a single manifold wall is utilized, and the corresponding end plate member 212a, 212b. Screen portion 206a, 206b extends continually and substantially from axis A to end closure 212a, 212b. Each screen portion 206a, 206b can comprise approximately one-half the entire length of the screen intake assembly <NUM>.

With reference to <FIG>, each screen portion 206a, 206b can include an underlying support structure <NUM>. The underlying support structure <NUM> of screen intake assembly <NUM> can comprise a plurality of spaced apart horizontal support bars <NUM> that are each arranged transversely to axis A. Each screen portion 206a, 206b and the corresponding underlying support structure <NUM> including support bars <NUM> can be fabricated based on the same principles as the embodiments disclosed in <CIT><CIT>and <CIT>.

As seen in <FIG>, a screen intake assembly <NUM> can comprise a variation of screen intake assembly <NUM> with a modification to the one or more manifold walls 208a, 208b. Instead of manifold walls 208a, 208b being positioned in proximity to axis A, manifold walls 308a, 308b can be spaced apart from axis A such that a central portion <NUM> defines its own screen portion 306c. As such, screen portions 306a, 306b each have a screen length 310a, 310b defined between the corresponding manifold wall 308a, 308b and a corresponding end plate member 312a, 312b. Screen portion 306c has a screen length 310c that is defined between the manifold walls 308a, 308b. Cooperatively, the screen portions 306a, 306b, 306c define a substantially continuous filtering surface between the end plate members 312a, 312b. As depicted, each screen portion 306a, 306b, 306c can comprise approximately one-third the entire length of the screen intake assembly <NUM>. In other embodiments, the screen portions 306a, 306b can have the same screen length 310a, 310b that differs from screen length 310c of the screen portion 306c.

A further variation to screen intake assemblies <NUM> and <NUM> is illustrated in <FIG> and <FIG> as screen intake assembly <NUM>. Each of screen portions 406a, 406b can be fabricated to include an external flange wall <NUM> while screen portion 406c can include a pair of opposed external flange walls <NUM>. Screen portion 406c can further include one or more external support rib <NUM> arranged transversely to axis A and extending between the opposed external flange walls <NUM>. Though not depicted, it will be understood that screen portions 406a, 406b can also include a pair of opposed external flange walls <NUM> such that end caps 412a, 412b are coupled to the respective external flange wall <NUM>. In addition, screen portions 406a, 406b can also include one or more external support ribs <NUM>. Through the use of the external flange walls <NUM>, on-site assembly or expansion of the screen intake assembly <NUM> can be quickly and easily accomplished. External flange walls <NUM> can also provide impact protection for the screen portions 406a, 406b, 406c by helping to prevent large objects such as sticks and logs from coming into direct contact with the screen portions 406a, 406b, 406c. It is understood that the use of external flange walls <NUM> can be secured by bolts or any other material or method that provides a secure closure of flanges and screen portions 406a, 406b, 406c without substantially impacting the integrity of the screen assembly <NUM>.

Referring now to screen intake assemblies <NUM>, <NUM> and <NUM>, each screen intake assembly can comprise a lower portion <NUM>, <NUM>, <NUM> as seen in <FIG>, <FIG>. As illustrated, these lower portions <NUM>, <NUM>, <NUM> can comprise a solid material such as stainless steel or copper-nickel tubing/piping so as to prevent fluid from penetrating the lower portion and entering the screen intake assemblies <NUM>, <NUM>, <NUM> without being filtered by the corresponding screen portions. In alternative embodiments, lower portions <NUM>, <NUM>, <NUM> can be incorporate their own screen portions similar to that previously described. In yet other embodiments, the lower portions <NUM>, <NUM>, <NUM> can be fabricated from a material having perforations such as slots or apertures that allow fluid intake. In all embodiments, materials selected for lower portions <NUM>, <NUM>, <NUM> should provide the necessary support for the screen intake assemblies <NUM>, <NUM>, <NUM> such that the structural support is not compromised.

In addition to the external features described with respect to screen intake assemblies <NUM>, <NUM> and <NUM> above, representative embodiments of the present invention can incorporated a variety of internal structures to adjust flow performance and to increase structural strength. As illustrated in <FIG>, an internal flow modifier <NUM> can be contained within a screen intake assembly, for example, any of screen intake assemblies <NUM>, <NUM>, <NUM> and <NUM>. Generally, internal flow modifier <NUM> can comprise a perforated flow modifier pipe <NUM>, an internal flow modifier pipe <NUM>, one or more radial support members <NUM> and a lower portion <NUM> that is fluidly coupled to the internal flow modifier pipe <NUM>. Perforated flow modifier piper <NUM> can comprise a solid pipe or tube-style materials having a plurality of spaced apart slots <NUM> to allow fluid to enter the internal flow modifier pipe <NUM>. The size, shape and spacing of slots <NUM> to allow for even flow intake along the length of the perforated flow modifier pipe <NUM>, thereby reducing pressure drops and assist in avoiding turbulent flow. Lower portion <NUM> can have a cross section substantially equal to or larger than perforated flow modifier pipe <NUM>. Lower portion <NUM> can further comprise a divider plate <NUM> providing structural support as well as further dividing incoming flow coming from the various screen portions.

<FIG> and <FIG> illustrate other alternative embodiments of internal flow modifiers <NUM> and <NUM> respectively. Each of the internal flow modifiers <NUM>, <NUM> comprise a perforated flow modifier pipe <NUM>, <NUM>, an internal flow modifier pipe <NUM>, <NUM>, one or more radial supports <NUM>, <NUM>, lower portion <NUM>, <NUM>, and an intake portion (not shown). According to embodiments, perforated flow modifier pipe <NUM>, <NUM> comprises a solid material with spaced apart slots <NUM>, <NUM> to allow fluid intake. In representative embodiments, lower portions <NUM>, <NUM> can have a cross section substantially equal to the perforated flow modifier pipe <NUM>, <NUM>. In embodiments, the cross section of the perforated flow modifier pipe <NUM>, <NUM> and lower portion <NUM>, <NUM> can be sized to accommodate a variety of fluid intake assemblies.

<FIG> illustrate another alternative embodiment of an internal flow modifier <NUM>. Internal flow modifier <NUM> can comprise a perforated flow modifier piper <NUM>, inlet an internal flow modifier piper <NUM>, one or more radial supports <NUM>, lower portion <NUM>, and an intake portion (not shown). According to embodiments, perforated flow modifier pipe <NUM> can comprise a solid material with spaced apart apertures <NUM> to allow even flow intake along the length of the perforated flow modifier pipe <NUM>, thereby reducing pressure drops and assisting to avoid turbulent flow. In embodiments, the cross section of perforated flow modifier pipe <NUM> and lower portion <NUM> can be sized to accommodate a variety of fluid intake assemblies.

As illustrated in <FIG>, an embodiment of an internal flow modifier <NUM> can comprise circumferential support members <NUM> and circumferential end portions 922a, 922b. According to embodiments, circumferential supports <NUM> are coupled to a perforated internal flow modifier <NUM> and end portions <NUM> can be coupled to screen portions (not shown). Both circumferential supports <NUM> and end portions <NUM> provide support to the exterior screen portions. Each of the circumferential supports <NUM> can include a variety of flow apertures 920a, 920b to assist in moderating fluid flow within a screen intake assembly. In certain embodiments, the flow apertures 920a between adjacent circumferential supports <NUM> can be positioned along the same radial axis while in other embodiments, flow aperture 920a can be positioned along the same radial axis as flow aperture 920b or on the adjacent circumferential support <NUM>. Yet in other representative embodiments, adjacent circumferential supports <NUM> can be arranged so that none of the flow apertures 920a, 920b are aligned in the same radial axis.

According to an alternative embodiment as depicted in <FIG>, a fluid intake assembly <NUM> can be designed for expansion such that screen portions <NUM> and an internal flow modifier <NUM> can be selectively added to accommodate desired liquid intake rates. Generally, fluid intake assembly can comprise a center manifold <NUM> about which a manifold screen portion <NUM> can be attached. On either side of the manifold screen portion <NUM>, a plurality of individual screen portions 1002a, 1002b, 1002c, 1002d can be operably coupled together. Manifold screen portion <NUM> can having a manifold screen portion length 1008a while the individual screen portions 1002a, 1002b, 1002c, 1002d each have a corresponding screen portion length 1010a, 1010b, 1010c, 1010d such that an intake assembly screen length 1000a is cooperatively defined by the manifold screen portion length 1008a and the screen portion lengths 1010a, 1010b, 1010c, 1010d. As illustrated, the manifold screen portion <NUM> and individual screen portions 1002a, 1002b, 1002c, 1002d can be operably connected using manifold walls <NUM> or section walls <NUM>. As illustrated, the manifold walls <NUM> and section walls <NUM> can be located internally of the fluid intake assembly <NUM> though it will be understood that the manifold walls <NUM> and section walls <NUM> could be located externally, for example, as external flange walls similar to external flange wall <NUM> of the embodiment shown in <FIG> and <FIG> so as to simply onsite assembly and expansion. The internal flow modifier <NUM> can similarly comprise a plurality of flow modifier sections 1004a, 1004b, 1004c, 1004b that are operably coupled to a central flow modifier <NUM> located within the center manifold <NUM>. The length and arrangements of the individual flow modifier sections 1004a, 1004b, 1004c, 1004d can be individually tailored based on desired performance as well as the intake screen assembly length 1000a. In one representative embodiment, the internal flow modifier sections 1004a, 1004b, 1004c, 1004d and central flow modifier <NUM> can define a perforated flow modifier pipe <NUM> and an internal flow modifier pipe <NUM>. The internal flow modifier <NUM> can further comprise one or more converging flow modifiers 1020a and 1020b coupled manifold walls <NUM>, and inlet pipe portion <NUM>. With the expandable nature of fluid intake assembly <NUM>, an almost infinite arrangement of screen portions <NUM> and internal flow modifier <NUM> can be fabricated or assembled on-site. In some instances, existing fluid intake assemblies <NUM> can be contracted or expanded on-site as fluid needs change at a point of use.

As illustrated and described with reference to the previous embodiments, various fluid intake assembly designs are contemplated in which the one or more screen members are fabricated so as to define a substantially round or circular cross-sectional area between the closure members/end plates. Alternatively, there may be installations, for example, locations having shallow depths such as rivers, where it would be advantageous to have a non-circular cross-section to reduce an overall height, or even width, of the screen intake assembly. For example, a screen intake assembly <NUM> as shown in <FIG> can comprise a reduced height design <NUM> having a non-circular cross-section <NUM>, herein illustrated as a substantially oval-like cross-section <NUM> for a pair of screen portions 1107a, 1107b and a central tee-portion 1107c. Non-circular cross-section <NUM> is herein defined by each of the screen portions 1107a, 1107b and central tee-portion 1107c having a screen portion height 1109a that is less than a screen portion width 1109b. Though not illustrated, it will be understood that there may be installation advantages wherein the non-circular cross-section is essentially reversed from that shown in <FIG> such that the screen portion height 1109a is greater than the screen portion width 1109b. Still in other embodiments, it may be advantageous to have other geometrical configurations for the non-circular cross-section <NUM> including, example, squares, rectangles, triangles pentagons, hexagons, octagons and the like. As illustrated, screen portions 1107a, 1107b can each include corresponding exterior screen members 1108a, 1108b and can include a corresponding closure member or end plate 1110a, 1110b that define oval-like perimeters 1112a, 1112b that substantially resemble the oval-like cross-section <NUM>. The central tee-portion 1107c can include a central exterior screen member <NUM> as well as a manifold <NUM> for delivering a filtered fluid to a point of use. The exterior screen members 1108a, 1108b and central exterior screen member <NUM> can comprise wedge wire or Vee-Wire ® style screens which are selected to provide desired filtering characteristics as well as desired flow characteristics including, for example, flow capacity and flow velocity. The manifold <NUM> can further comprise an outlet conduit <NUM> that can be fluidly connected to an internal flow modifier <NUM>. In order to accommodate the oval-like cross-section <NUM>, the internal flow modifier <NUM> can comprise a central collector <NUM> and a plurality of lateral collectors <NUM> configured to provide desirable flow characteristics within the screen intake assembly <NUM> and taking into consideration the non-circular nature of the oval-like cross-section <NUM>. One or more of the central collectors <NUM> and the lateral collectors <NUM> can comprise perforations or slots <NUM> to vary flow characteristics into the manifold <NUM>. Likewise, wedge wire style screens can be positioned along the screen members 1108a, 1108b, end plates 1110a, 1110b and/or the central tee-section <NUM> to get a desired flow capacity and other flow characteristics.

In addition to the variety of configurations for screen intake assemblies described previously, it can be advantageous to vary the construction technique of the individual screen portions themselves. For example, a conventional screen filter <NUM> of the prior art is shown in <FIG> Generally, a continuous spool of v-shaped wire <NUM> is continually wrapped about and welded to one or more support members <NUM>. Generally, a wire gap <NUM> is defined between adjacent corners <NUM> of the adjacently wrapped and welded v-shaped wire <NUM>. A gap length <NUM> of the wire gap <NUM> generally equates to the size of particulates filtered or "removed" from fluid that passes through the filer screen <NUM>, i.e., the filter rating.

Not only can the disclosed screen intake assemblies of the current invention utilize the conventional screen filter <NUM> but they can also use an improved screen filter <NUM> as shown in <FIG>. Screen filter <NUM> similarly utilizes one or more support members <NUM> but uses two different sized v-shaped wires, a first v-shaped wire <NUM> and a second v-shaped wire <NUM>. First v-shaped wire <NUM> can be defined by a first wire height 1251a and a first wire width 1251b while the second v-shaped wire <NUM> is defined by a second wire height 1252a and a second wire width 1252b. As illustrated, the first wire height 1251a and first wire width 1251b can be larger than the second wire height 1252a and second wire width 1252b such that a first cross-sectional area 1251c (of the first v-shaped wired <NUM>) is greater than that of a second cross-sectional area 1252c (of the second v-shaped wire <NUM>). As illustrated, first cross-sectional area 1251c is larger than that of the second cross-sectional area 1252c such that a first wire gap <NUM> is defined between adjacent wraps of the first v-shaped wire <NUM> while a second wire gap <NUM> is defined between the second v-shaped wire <NUM> and the first v-shaped wire <NUM> on either side of the second v-shaped wire <NUM>. As illustrated, first wire gap <NUM> can have a first gap length <NUM> that is substantially larger than a second gap length <NUM> of the second wire gap <NUM>. The second wire gap <NUM> can generally equate to the filter rating of the improved screen filter <NUM> while the first wire gap <NUM> defines an initial rough filter that can reduce an effective top surface velocity in an attempt to reduce impingement of wildlife and/or debris at the second wire gap <NUM>. For example, first wire gap <NUM> can be sized such that a fluid velocity through the first wire gap <NUM> is equal or less than about <NUM> ft/sec such that aquatic life such as, for example, fish can avoid being trapped against an exterior of the improved screen filter <NUM>. In addition, when the second v-shaped wire <NUM> is smaller than that of the v-shaped wire <NUM> of conventional screen filter <NUM>, the number of second wire gaps <NUM> defined in the available surface area of the improved screen filter <NUM> will be larger than the number of wire gaps <NUM> in the same surface area of the conventional screen filter <NUM>. By providing more of the second wire gaps <NUM>, screen filter <NUM> provides more available filtering area than the conventional screen filter <NUM> so as to increase the overall capacity of any screen intake assembly utilizing the improved screen filter <NUM> while still maintaining a reduced fluid velocity at the exterior surface of the improved screen filter <NUM>. Depending upon desired flow characteristics, one or more of the first wire height 1251a, first wire width 1251b, second wire height 1252a and second wire height 1252b can be adjusted to selectively change one or both of the first wire gap <NUM> and second wire gap <NUM> to achieve desired fluid velocities through one or both of the first wire gap <NUM> and second wire gap <NUM>.

In yet another alternative embodiment, the various screen intake assemblies of both the prior art and the novel configurations disclosed herein can further incorporate a removal system for limiting attachment and/or detaching biofouling materials and other debris from a screen filter. For example, a removal system <NUM> can comprise an oscillator assembly <NUM> to continually or selectively induce vibration to the screen assembly to deter and/or remove contaminants from the screen assembly as shown in <FIG>. Oscillator assembly <NUM> can comprise a device capable of generating ultrasonic or low frequency vibrations. Generally, a screen intake assembly <NUM> can comprise a central portion <NUM> operably coupled to one or more screen portions <NUM>. The oscillator assembly <NUM> can be operably attached to the central portion <NUM> such that vibrations created by the oscillator assembly <NUM> are transmitted through the central portion <NUM> and to a screen filter <NUM> on the exterior of each screen portion <NUM>. As shown in <FIG>, the oscillator assembly <NUM> can be operably connected to a remote power source <NUM> for example, an electrical grid or an onshore/barge/rig mounted generator. Alternatively, the oscillator assembly <NUM> can be powered using a turbine or propeller style assembly <NUM> to convert a filtered fluid flow through the central portion <NUM> to rotational energy that can directly power the oscillator assembly <NUM> or to generate energy for storage in a battery source that is integral to or located in proximity to the oscillator assembly <NUM> as shown in <FIG>.

In a variation to the removal system <NUM>, a screen intake assembly <NUM> can comprise a flow-through oscillation system <NUM> to continually induce vibration absent any moving or powered assemblies as shown in <FIG>. As illustrated, the screen intake assembly <NUM> can comprise a pair of screen portions 1354a, 1354b that are operably connected to a central-tee portion <NUM>. The screen intake assembly <NUM> can further comprise an internal flow modifier system <NUM> to provide desirable flow characteristics through the screen portions 1354a, 1354b. The internal flow modifier system <NUM> can further comprise one or more flow-through oscillators <NUM> that are positioned between the internal flow modifier system <NUM> and the screen portions 1354a, 1354b. As best seen in <FIG>, each flow-through modifier <NUM> can comprise a substantially tubular body <NUM> defining an inlet <NUM>, a fluid channel <NUM> and an outlet <NUM>. Outlet <NUM> can define a connecting member <NUM> that attaches to an aperture <NUM> in the internal flow modifier system <NUM> such that the fluid channel <NUM> is fluidly connected to an interior flow-though portion <NUM> of the internal flow modifier system <NUM>. As fluid flows into the internal flow modifier system <NUM> and through the interior flow-though portion <NUM>, suction is created at the outlet <NUM> such that fluid is drawn into the inlet <NUM> and through the fluid channel <NUM>. Inlet <NUM> and/or the fluid channel <NUM> can be configured such that the fluid flow through the flow-through oscillator <NUM> generates a resistance pattern or "whistle" that causes vibration which is ultimately transmitted to the screen portions 1364a, 1364b through the physically connection of the internal flow modifier system <NUM> to the central tee-portion <NUM>. This resistance pattern or "whistle" is essentially continuous as long as fluid is flowing into the interior flow-through portion <NUM>. As such, no external or stored energy source is required for operation and there are no moving parts or mechanical assemblies requiring maintenance. As such, the flow-through oscillation system <NUM> operates to limit attachment and/or accumulation of debris or biofouling materials in a continuous and economical manner.

The various screen intake assemblies of both the prior art as well as the novel configurations disclosed herein can further incorporate internal cleaning systems to remove accumulated debris and biofouling. As shown in <FIG>, it is well known in the prior art to utilize an internal air burst system <NUM> within a screen intake assembly <NUM> to delivery pulses of pressurize air <NUM> to an interior portion <NUM> of the screen intake assembly <NUM>. Generally, the internal air burst system <NUM> comprises an airburst pipe <NUM> positioned in proximity to a lower portion <NUM> of a screen portion <NUM>. Typically, the airburst pipe <NUM> is in fluid communication with a remotely located air compressor such as, for example, a compressor located onshore, on a barge or on a rig. The airburst pipe <NUM> can be attached an airburst manifold located within a central portion of the screen intake assembly. Where the screen intake assembly comprises multiple screen portions <NUM>, an airburst pipe <NUM> can be located within each screen portion <NUM> and each airburst pipe <NUM> can be operably connected to the airburst manifold. Generally, pulses of pressurized air can be supplied through the airburst pipe <NUM> whereby the pulse of pressurize air starts displacing water proximate the lower portion <NUM> and subsequently expands to fill and displace water throughout the screen portion <NUM> to displace contaminants from the surface of the screen portion <NUM>.

In an improved airburst system <NUM> of the present invention, a plurality of airburst pipes can be positioned at a variety of locations in addition to the lower portion <NUM> as shown in <FIG>. For example, airburst pipe 1422a can be located proximate the lower portion <NUM>, airburst pipes 1422b, 1422c can be located proximate opposed sides 1424a, 1424b of the screen portion <NUM> and airburst pipe 1422d can be located proximate an upper portion <NUM> of the screen portion <NUM>. While the improved airburst system <NUM> is illustrated as having four airburst pipes 1422a, 1422b, 1422c, 1422d, it will be understood that variables including, for example, the size of a screen intake assembly and the quality of the fluid being filtered can lead to designs utilizing either fewer airburst pipes with at least two being required or more than four airburst pipes. The airburst pipes 1422a, 1422b, 1422c, 1422d can all be operably connected to an airburst manifold located within a central portion <NUM> of the screen intake assembly <NUM>. In the event that the screen intake assembly <NUM> comprises both fist and second screen portions 1430a, 1430b, each of the screen portions 1430a, 1430b can include the same arrangement of airburst pipes 1422a, 14222b, 1422c, 14222d. In some embodiments, pulses of pressurized air <NUM> can be simultaneously delivered through each airburst pipe 1422a, 1422b, 1422c, 1422d as shown in <FIG>. Generally, the pulses of pressurized air are delivered through nozzles 1425a, slots, <NUM> or similar apertures positioned along the length of each airburst pipe 1422a, 1422b, 1422c, 1422d. Alternatively, the pulses of pressurize air can be radially, sequentially delivered through the airburst pipes 1422a, 1422b, 1422c, 1422d as shown in <FIG>. In yet another alternative arrangement, the pulses of pressurized air can be sequentially delivered along an intake length <NUM> defined between a first end <NUM> and a second end <NUM> of a screen intake assembly <NUM> as seen in <FIG>. While the screen intake assembly <NUM> of <FIG> contains first and second screen portions 1443a, 1443b connected to a central tee portion <NUM>, the same principle can be applied to provide pulses of pressurize air along an intake length that makes use of only a single screen portion. The particular arrangement and sequence of the pressurized air pulse delivery will generally be tailored to the installation and can depend upon the installation conditions and the type and quantity of particulate and biofouling accumulation.

Yet another variation of a screen intake assembly <NUM> of the present invention is shown in <FIG> and <FIG>. As illustrated, screen intake assembly <NUM> includes a central tee-portion <NUM> and a screen portion <NUM>. While only a single screen portion <NUM> is shown, it will be understood that additional screen portions can be operably connected to the central tee-portion <NUM> based upon fluid flow requirements. The screen intake assembly <NUM> includes an internal flow modifier assembly <NUM> and an integrated self-cleaning system <NUM>. Generally, the internal flow modifier assembly <NUM> is configured to promote desirable flow conditions through a screen filter <NUM> on one or both of the central tee-portion <NUM> and the screen portion <NUM>. As seen in <FIG>, the integrated self-cleaning system <NUM> can comprise an intake scoop <NUM> that is operably connected to a flow modifier conduit <NUM> that is positioned within the central tee-portion <NUM>. One or more cleaning inlet pipes <NUM> can be fluidly connected to the intake scoop <NUM> such that a portion of fluid flowing between the intake scoop <NUM> and the central tee-portion <NUM> is directed into the cleaning inlet pipes <NUM>. The cleaning inlet pipes <NUM> are fluidly connected to one or more cleaning pipes <NUM> that are positioned axially and radially along a length defined by one or or both of the central tee-portion <NUM> and screen portion <NUM>. As shown, the one or more cleaning pipes <NUM> can be positioned within the screen intake assembly <NUM> and in proximity to an interior surface of the screen filter <NUM>. Alternatively, the one or more cleaning pipes <NUM> can be positioned outside the screen intake assembly <NUM> and in proximity to an exterior surface of the screen filter <NUM>. Each cleaning pipe <NUM> generally includes a plurality of spaced apart apertures <NUM>, slots or perforations. In some instances, a nozzle <NUM> can be operably mounted within each aperture <NUM> as shown in <FIG>. The fluid flow is directed through the cleaning inlet pipes <NUM>, into the cleaning pipes <NUM> and out the apertures <NUM>/nozzles <NUM>. The fluid flow out of the apertures <NUM>/nozzles <NUM> can be directed against the screen filter <NUM> or along the screen filter <NUM> to dislodge and/or inhibit the attachment of any contaminants. Furthermore, the integrated self-cleaning system <NUM> is a passive system requiring no external power source and no moving parts that could require ongoing maintenance. In a version of the integrated self-cleaning system <NUM> as shown in <FIG>, the intake scoop <NUM> can be located within the internal flow modifier assembly <NUM> at a location internal to the screen portion <NUM> as opposed to the central tee-portion <NUM>.

Various embodiments of systems, devices, and methods have been described herein. These embodiments are given only by way of example and are not intended to limit the scope of the claimed inventions. It should be appreciated, moreover, that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the claimed inventions.

Persons of ordinary skill in the relevant arts will recognize that the subject matter hereof may comprise fewer features than illustrated in any individual embodiment described above. The embodiments described herein are not meant to be an exhaustive presentation of the ways in which the various features of the subject matter hereof may be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, the various embodiments can comprise a combination of different individual features selected from different individual embodiments, as understood by persons of ordinary skill in the art. Moreover, elements described with respect to one embodiment can be implemented in other embodiments even when not described in such embodiments unless otherwise noted.

Claim 1:
A screen intake assembly (<NUM>) comprising:
a central manifold including a lower outlet portion (<NUM>) and tee-section (<NUM>);
a pair of screen sections (406a, 406b) fluidly connected on opposed sides of the tee-section (<NUM>); and
a central screen section (406c) substantially extending across the tee-section (<NUM>),
wherein the tee-section (<NUM>) includes at least two external flanged manifold walls (<NUM>) and at least one external support rib (<NUM>) residing between the at least two external flanged manifold walls (<NUM>), said at least one eternal support rib (<NUM>) arranged transversely to a central axis (A) defined by the lower outlet portion (<NUM>).