Patent Description:
Gas turbines are used throughout the world in many diverse applications and environments. This diversity creates a number of challenges to air filtration systems, necessitating various solutions depending on the environmental contaminant(s)/particulates, gas turbine platform technology, and/or fuel quality. For example, gas turbines which operate in deserts or high dust concentration areas, along coastlines, in other environments in which the turbine is exposed to severe air quality contaminations, and/or high efficiency gas turbines operating at high operational temperatures, face significant challenges with respect to engine performance, reliability, and/or maintainability where there is a compromise or breach in the air inlet of the gas turbine system. Such challenges may include the erosion, corrosion and/or failure of various turbine components.

To prevent debris and/or particles from entering the gas turbine, the filtration systems typically include multiple stages of filtration components that filter various sizes of debris and/or particles prior to the working fluid (e.g., filtered air) entering the compressor of the gas turbine. However, these components included in conventional filtration systems can become damaged by the same debris and may no longer filter out the debris and particles as desired. Additionally, or alternatively, the components included in conventional filtration systems may not operate as desired. Existing solutions have focused on adding filtration stages or components, which provides additional obstructions to the inlet airflow to the gas turbine. In particular, existing filtration systems may decrease the airflow across such systems by the addition of filter stages, which negatively impacts the efficiency and performance of the gas turbine system, as a whole.

An existing solution is known from <CIT>.

In view of the above, there is a need for a system and method for inhibiting or preventing particulate and foreign object ingress in a gas turbine system that minimizes the effect on overall system efficiency and performance.

In an embodiment, a method for inhibiting particulate ingress in a combustion system includes acquiring particulate ingress data, determining a probable particulate ingress location on an air inlet of the combustion system in dependence upon the particulate ingress data, and deploying a filter screen at the determined probable particulate ingress location to inhibit particulate ingress at the determined probable particulate ingress location.

In another embodiment, a turbine system includes a turbine having a compressor for compressing intake air, and an inlet filter housing in fluid communication with the compressor and having an array of air passages for ingress of the intake air, the inlet filter housing being configured to remove particulates from the intake air prior to passage of the intake air to the compressor. The inlet filter housing includes an array of air passages for receiving the intake air therethrough, and an array of filter screens generally corresponding to the array of air passages. The array of filter screens are individually movable between a retracted position where the intake air is permitted to bypass a respective filter screen, and a deployed position where the intake air passes through the filter screen. When in the deployed position, the filter screens are configured to remove the particulates from the intake air.

In yet another embodiment of the invention, a method for inhibiting particulate ingress in a combustion system includes the steps of providing an inlet duct in fluid communication with a turbine having a compressor, the inlet duct having an intake area for a flow of intake air, determining at least one location of particulate or foreign object ingress along the intake area, and moving a first subset of filter screens of an array of filter screens so as to extend across the flow of intake air at the location of particulate or foreign object ingress.

Reference will be made below in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference characters used throughout the drawings refer to the same or like parts. While embodiments of the invention are directed to a system and method for inhibiting particulate and foreign object ingress in gas turbine systems, embodiments of the invention are not so limited in this regard and are also applicable to a variety of systems including, for example, aero/marine, hydrogen/ammonia, etc. based turbine applications and, still further is also applicable to the removal of particulate, moisture and/or foreign objects in a flow of air to be utilized for any purpose (compression, cooling, heating, etc.).

As used herein, "downstream" and "upstream" are terms that indicate a direction relative to the flow of a fluid, such as the working fluid through the turbine engine or, for example, the flow of air through the combustor or coolant through one of the turbine's component systems. The term "downstream" corresponds to the direction of flow of the fluid, and the term "upstream" refers to the direction opposite to the flow. The terms "forward" and "aft," without any further specificity, refer to directions, with "forward" referring to the front or compressor end of the engine, and "aft" referring to the rearward or turbine end of the engine. Additionally, the terms "leading" and "trailing" may be used and/or understood as being similar in description as the terms "forward" and "aft," respectively. It is often required to describe parts that are at differing radial, axial and/or circumferential positions.

The "A" axis represents an axial orientation. As used herein, the terms "axial" and/or "axially" refer to the relative position/direction of objects along axis A, which is substantially parallel with the axis of rotation of the turbine system (in particular, the rotor section). As further used herein, the terms "radial" and/or "radially" refer to the relative position/direction of objects along a direction "R" (see, <FIG>), which is substantially perpendicular with axis A and intersects axis A at only one location. Finally, the term "circumferential" refers to movement or position around axis A (e.g., direction "C").

As used herein, "electrically coupled", "electrically connected", and "electrical communication" mean that the referenced elements are directly or indirectly connected such that an electrical current may flow from one to the other. The connection may include a direct conductive connection, i.e., without an intervening capacitive, inductive or active element, an inductive connection, a capacitive connection, and/or any other suitable electrical connection. Intervening components may be present.

Embodiments of the invention relate to systems and methods for inhibiting or preventing the ingress of particulates or foreign object debris in a combustion system, such as a gas turbine combustion system. In an embodiment, a method for inhibiting particulate ingress in a combustion system includes acquiring particulate ingress data, determining a probable particulate ingress location on an air inlet of the combustion system in dependence upon the particulate ingress data, and deploying a filter screen at the determined probable particulate ingress location to inhibit particulate ingress at the determined probable particulate ingress location.

<FIG> is a schematic illustration of a turbine system (e.g., gas turbine system <NUM>) according to an embodiment of the invention. Gas turbine system <NUM> includes a compressor <NUM> and an air filtration assembly <NUM> positioned upstream of and in fluid communication with compressor <NUM>. Compressor <NUM> is configured to compresses an incoming flow of filtered air <NUM> that is filtered by and flows from air filtration assembly <NUM> to compressor <NUM>, as discussed herein. Compressor <NUM> typically includes a plurality of rotatable blades including airfoils (not shown) and stationary nozzles (not shown) which work together to compress the filtered air <NUM> as it flows through compressor <NUM>. Compressor <NUM> delivers a flow of compressed air <NUM> to a combustor <NUM>. Combustor <NUM> mixes the flow of compressed air <NUM> with a pressurized flow of fuel <NUM> and combusts the mixture to create a flow of combustion gases <NUM>. Although only a single combustor <NUM> is shown, gas turbine system <NUM> may include any number of combustors <NUM>. The flow of combustion gases <NUM> is, in turn, delivered to a turbine <NUM>. Similar to compressor <NUM>, turbine <NUM> also typically includes a plurality of turbine blades including airfoils and stator vanes. The flow of combustion gases <NUM> drives turbine <NUM>, and more specifically the plurality of turbine blades of turbine <NUM>, to produce mechanical work. The mechanical work produced in turbine <NUM> drives compressor <NUM> via a rotor <NUM> extending through turbine <NUM> and may be used to drive an external load <NUM>, such as an electrical generator and/or the like.

As also shown in <FIG>, gas turbine system <NUM> may also include an exhaust frame or exhaust diffuser <NUM>. The exhaust frame <NUM> is positioned adjacent to turbine <NUM> of the gas turbine system <NUM>. More specifically, exhaust frame <NUM> may be positioned adjacent to turbine <NUM> and may be positioned substantially downstream of turbine <NUM> and/or the flow of combustion gases <NUM> flowing from combustor <NUM> to turbine <NUM>.

Subsequent to combustion gases <NUM> flowing through and driving turbine <NUM>, combustion gases <NUM> may be exhausted, flow-through and/or discharged through exhaust frame <NUM> in a flow direction (D). In the non-limiting example shown in <FIG>, combustion gases <NUM> may flow through exhaust frame <NUM> in the flow direction (D) and may be discharged from gas turbine system <NUM> (e.g., to the atmosphere). In another non-limiting example (not shown) where gas turbine system <NUM> is part of a combined cycle power plant (e.g., including gas turbine system and a steam turbine system), combustion gases <NUM> may discharge from exhaust frame <NUM>, and may flow in the flow direction (D) into a heat recovery steam generator of the combined cycle power plant.

As further shown in <FIG>, and discussed in detail hereinafter, air filtration assembly/system <NUM> of gas turbine system <NUM> may include a plurality of sensors, components, devices, and/or systems configured to detect the presence of particulates and/or foreign objects present in intake air, and to filter such particulates and/or foreign objects to produce filtered air <NUM> that is then delivered to the compressor <NUM>. In an embodiment, particulates and/or foreign objects may include dust, sand, water and/or other debris. As discussed herein, the detection of particles and/or improved filtration of particles using air filtration assembly <NUM> may reduce, inhibit or prevent damage to the internal components of gas turbine system <NUM> which receive and/or utilize filtered air <NUM> during operation. Furthermore, the implementation of air filtration assembly <NUM> may maintain/improve operational efficiencies of gas turbine system <NUM> by reducing/eliminating the number of undesirable particles included in filtered air <NUM>.

As shown in <FIG>, air filtration assembly <NUM> of gas turbine system <NUM> may include an air inlet duct <NUM> (also referred to herein as inlet filter housing <NUM>), which may be in fluid communication with compressor <NUM> of gas turbine system <NUM> for providing filtered air <NUM> thereto. Inlet filter housing <NUM> may be formed from any suitable duct components and/or duct system that may be configured to receive an intake air <NUM> and include or house at least one component, device, and/or system therein to filter intake air <NUM> from the atmosphere surrounding the inlet filter housing <NUM>. The inlet filter housing <NUM> may include an inlet <NUM> positioned and/or formed on a first end of the inlet filter housing <NUM>, an outlet <NUM> positioned opposite inlet <NUM> on a second end of the inlet filter housing <NUM>, and an internal cavity <NUM> extending between inlet <NUM> and outlet <NUM>.

Inlet <NUM> may receive intake air <NUM> including particle(s) <NUM> and may subsequently pass intake air <NUM> through internal cavity or space <NUM> of the inlet filter housing <NUM>/inlet ducting to outlet <NUM> to be provided to compressor <NUM>. As discussed herein, intake air <NUM> including particles <NUM> may move through internal cavity <NUM> of air inlet filter housing <NUM> and interact and/or be processed by the component(s), device(s), and/or system(s) of air filtration assembly <NUM> within the inlet filter housing <NUM> to filter particles <NUM> from intake air <NUM>. Filtering particles <NUM> from intake air <NUM> may form filtered air <NUM> utilized as working fluid by compressor <NUM>, as indicated above.

In an embodiment, the air filtration assembly <NUM> may include a plurality of vane filters <NUM> that may filter large particles <NUM> from intake air <NUM>. In an embodiment, the vane filters <NUM> may be vane separators or coalescers that function to accumulate water droplets and shed them away through drains or through coalescing. More specifically, air filtration assembly <NUM> may include a plurality of vane filters <NUM> positioned on, at, within, and/or adjacent inlet of inlet <NUM> of air inlet filter housing <NUM>. The plurality of vane filters <NUM> positioned at inlet <NUM> may provide the first form of filtration of intake air <NUM> for removing particles <NUM> included in intake air <NUM>. The plurality of vane filters <NUM> may be formed as any suitable filtering component that may be configured to remove and/or filter out large particles and/or debris that may be found in intake air <NUM>, such as, sand grains, dirt, rain drops, snow, and other undesirable debris. In non-limiting examples, the plurality of vane filters <NUM> may be positioned within respective weather hoods <NUM> located on the face of the inlet filter housing <NUM>, as discussed below. In an embodiment, the vane filters <NUM> may be omitted.

As further shown in <FIG>, an array of fabric filters <NUM> may also be included in air filtration assembly <NUM>. In the non-limiting example shown in <FIG>, the array of fabric filters <NUM> may be positioned in inlet filter housing <NUM> and, more specifically, in internal cavity <NUM> of inlet filter housing <NUM>. Additionally, the array of fabric filters <NUM> may be positioned in the inlet filter housing <NUM> downstream of inlet <NUM> and the plurality of vane filters <NUM>. The array of fabric filters <NUM> may be formed as any suitable filtering components and/or devices that may be configured to further filter particles <NUM> from intake air <NUM> flowing therethrough. That is, the array of fabric filters <NUM> may be configured to filter finer and/or smaller particulates included in intake air <NUM> that may not necessarily be filtered by the plurality of vane filters <NUM>. In the non-limiting example shown, the array of fabric filters <NUM> may be formed as a plurality of fabric filter bags. In another non-limiting example, fabric filters <NUM> may be formed from a plurality of conical fabric filters. The array of fabric filters <NUM> may also be formed as either pulsed fabric filters or static fabric filters.

Turning briefly to <FIG>, in an embodiment, the air filtration assembly <NUM> may additionally include a plurality of filter screens <NUM> arranged at the face of the inlet filter housing <NUM> (in addition, or alternative to, the vane filters <NUM>), which are each selectively movable between a retracted position where the intake air <NUM> bypasses, or flows around (but not through) the filter screen <NUM> (see <FIG>), and a deployed position where the filter screen <NUM> extends across a respective inlet passage such that the intake air <NUM> flows through the filter screen <NUM> (see <FIG>). In an embodiment, each weather hood <NUM> at the inlet <NUM> may form an inlet passage for the flow of intake air <NUM>, and each weather hood <NUM> may include an associated filter screen <NUM>, as discussed below. In particular, in an embodiment, the inlet <NUM> includes an array of weather hoods <NUM> forming a generally rectangular array or matrix of air inlet passages, each of which includes a respective filter screen <NUM>, the positions of which are independently controllable.

With reference to <FIG>, in an embodiment, the each filter screen <NUM> is connected to, otherwise associated with, an electrical relay or switch <NUM> that is in communication or otherwise electrically coupled with a controller <NUM> for controlling the position of each filter screen <NUM> (i.e., retracted or deployed). For example, in an embodiment, the relays <NUM> may be associated with a respective actuator (e.g. a mechanical, hydraulic, pneumatic actuator or the like) for moving each filter screen <NUM> between the retracted and deployed positions under control of the controller <NUM>.

As shown in <FIG>, in one implementation, the filter screens <NUM> may be pivotally connected to the inlet filter housing <NUM> (or the weather hoods <NUM> thereof) such that they may rotate into and out of the deployed and retracted positions under control of the controller <NUM> (via relays <NUM>), as indicated by the arrows. With reference to <FIG>, in another embodiment, the filter screens <NUM> may be slidably connected to the inlet filter housing <NUM> (or the weather hoods <NUM> thereof) such that they are slidably moveable between the retracted and deployed positions, as indicated by the arrows. In an embodiment, the filter screens <NUM> may be mounted on rollers, slides or tracks for facilitating the deployment and retraction of the filter screens <NUM>.

In an embodiment, the filter screens <NUM> are thin mesh screens having an anti-rebounding coating, and are shaped and dimensioned so as to fully extend across each inlet passage of a respective weather hood <NUM> when in the extended/deployed position so as to ensure that all of the inlet air <NUM> entering such passage passes through the filter screen <NUM>. As used herein, "anti-rebounding" means configured and formulated so as to deflect or direct entrained particulates and foreign object debris out of or away from the primary flow of intake air. In an embodiment, the coating is an anti-rebounding coating, and/or a coating with hydrophilic or hydrophobic or coalescing properties/characteristics and/or corrosion resistance properties. In an embodiment, the specific formulation and characteristics of the coating may be selected in dependence upon the type of particulate that is to be kept out of the flow of intake air (e.g., sand, dust or moisture). In some embodiments, the coating may be selected to have a high bouncing effect on particulates. In other embodiments, the coating may be selected to have a low bouncing effect on particulates. That is, the composition of the coating can be altered or chosen to achieve the relevant property of either low bouncing or high bouncing effect based on the application of the coating (e.g., in arid or high moisture environments). In an embodiment the coating may be Ti-<NUM>-<NUM> or Polyurethane.

Referring back to <FIG>, air filtration assembly <NUM> may also include a silencer assembly <NUM>. Silencer assembly <NUM> may be positioned in air inlet filter housing <NUM> and/or in internal cavity <NUM> of air inlet filter housing <NUM>. As shown in <FIG>, silencer assembly <NUM> may be positioned downstream of the array of fabric filters <NUM>, and adjacent outlet <NUM> of inlet filter housing <NUM>. In the non-limiting example, intake air <NUM> may pass through silencer assembly <NUM> to form filtered air <NUM>, which may in turn be provided from silencer assembly <NUM> and/or outlet <NUM> of air filtration assembly <NUM> to compressor <NUM>, as discussed herein. Silencer assembly <NUM> may be formed as any suitable component, system, and/or assembly of components configured to reduce the "noise" of compressor <NUM> transmitted through the air inlet <NUM>. For example, silencer assembly <NUM> may be formed as a plurality of silencer panels that may muffle and/or reduce the noise associated with the operation of gas turbine system <NUM>.

The non-limiting example of air filtration assembly <NUM> shown in <FIG> also includes components, devices, and/or systems that may detect undesirable particles <NUM> in intake air <NUM>. More specifically, during operation of air filtration assembly <NUM> undesirable particles <NUM> included in intake air <NUM> may not be filtered by the plurality of vane filters <NUM>, the filter screens <NUM>, and/or the array of fabric filters <NUM>. Particles <NUM> may not be filtered due to their size (e.g., neither filtered by vane filters <NUM> nor fabric filters <NUM>), and/or due to faults or deficiencies in the plurality of vane filters <NUM> and/or the array of fabric filters <NUM>. For example, and as shown in <FIG>, particles <NUM> may pass through, not be filtered by, and/or may flow downstream of the array of fabric filters <NUM> due to particle size, filter tears, and/or holes formed in some of the fabric filters <NUM> or in other components of the assembly <NUM>, improper installation of fabric filters <NUM>, and/or per solving and recrystallization processes. The tears and/or holes may be formed in fabric filters <NUM> by debris (e.g., insects) that may flow past the plurality of vane filters <NUM>, improper installation and/or care of fabric filters <NUM>, manufacturing defects, and/or operational wear of fabric filters <NUM>. As a result, particles <NUM> included in intake air <NUM> may not be filtered and/or collected by fabric filters <NUM> and may flow through the holes. As discussed herein, detecting particles <NUM> within the air inlet duct(s) beyond the plurality of vane filters <NUM>, filter screens <NUM>, and/or the array of fabric filters <NUM> may indicate that components of air filtration assembly <NUM> are not functioning properly and/or may require maintenance (e.g., replacement of torn fabric filters). This in turn, may reduce/prevent damage to compressor <NUM>, combustor <NUM>, and/or turbine <NUM> by particles <NUM> during operation, and/or may maintain/improve operational efficiencies of gas turbine system <NUM> by reducing/eliminating the number of undesirable particles <NUM> included in filtered air <NUM>.

As shown in <FIG>, air filtration assembly <NUM> may include an electrostatic component <NUM> positioned in inlet filter housing <NUM>. More specifically, electrostatic component <NUM> may be positioned within internal cavity <NUM> of inlet filter housing <NUM>, downstream of the array of fabric filters <NUM>. Additionally as shown, electrostatic component <NUM> may be positioned upstream of silencer assembly <NUM> of air filtration assembly <NUM>. Electrostatic component <NUM> may be configured to charge particles <NUM> that pass through the plurality of vane filters <NUM> and/or the array of fabric filters <NUM>, and in turn through and/or over electrostatic component <NUM>. As discussed herein, charged particles <NUM> included in intake air <NUM> may allow for easier and/or improved detection of particles <NUM> before particles <NUM> reach compressor <NUM> of gas turbine system <NUM>.

According to the invention and as shown in <FIG>, electrostatic component <NUM> is formed and/or configured as a plurality or matrix of ionizers <NUM> (hereafter, "matrix of ionizers <NUM>"). The matrix of ionizers <NUM> may be positioned within inlet filter housing <NUM>, downstream of the array of fabric filters <NUM>. The matrix of ionizers <NUM> may span over the entirety of a front cross-sectional area of inlet duct <NUM>. That is the matrix of ionizers <NUM> forming electrostatic component <NUM> may span and/or cover the entirety of an area of internal cavity <NUM> of inlet duct <NUM>, such that every particle <NUM> that may pass the array of fabric filters <NUM> must pass over and/or pass through the matrix of ionizers <NUM>. In the non-limiting example, the matrix of ionizers <NUM> forming electrostatic component <NUM> may be formed as a plurality of matrix of corona chargers or corona wires. However, it is understood that ionizers <NUM> of filtration assembly <NUM> may be formed from any suitable device, component, and/or system that may be configured to charge intake air particles <NUM>, as discussed herein.

In a non-limiting example, control system <NUM> and turbine control system <NUM>, may be formed or configured as single, stand-alone systems or computing devices that function separately, as discussed herein, and are in communication with one another. Alternatively, control system <NUM> may be integrally formed within, in communication with and/or formed as a part of turbine control system <NUM>. However embodied, control system <NUM> and turbine control system <NUM> may be formed of any suitable device and/or system that may be configured to obtain and process information relating to gas turbine system <NUM>, and control the various components of gas turbine system <NUM> and air filtration assembly <NUM>.

Air filtration system <NUM> may also include at least one electrostatic sensor <NUM>. As shown in <FIG>, electrostatic sensor(s) <NUM> may be operably coupled to and/or in operable communication with control system <NUM>. Electrostatic sensor(s) <NUM> may be positioned downstream of the matrix of ionizers <NUM>. Additionally, electrostatic sensor(s) <NUM> may be positioned upstream of compressor <NUM>. In the non-limiting example, electrostatic sensor(s) <NUM> may also be positioned downstream of inlet filter housing <NUM> and silencer assembly <NUM>, respectively. In other non-limiting examples (not shown) electrostatic sensor(s) <NUM> may be positioned upstream of silencer assembly <NUM> and within air inlet duct <NUM>, respectively, or alternatively electrostatic sensor(s) <NUM> may be positioned within silencer assembly <NUM> as long as electrostatic sensor(s) <NUM> are positioned downstream of the matrix of ionizers <NUM>, but upstream of compressor <NUM>. In the non-limiting example, electrostatic sensor(s) <NUM> may be in fluid communication and/or positioned within a conduit <NUM> fluidly coupling air filtration assembly <NUM> and compressor <NUM>. That is, electrostatic sensor(s) <NUM> may be in communication with conduit <NUM> that may deliver filtered air <NUM> to compressor <NUM>.

Electrostatic sensor(s) <NUM> may be formed from any suitable sensor and/or device that may be configured to detect the charged particles <NUM> of intake air <NUM> that may be previously charged by the matrix of ionizers <NUM> and flow past electrostatic sensor(s) <NUM> (e.g., particulate matter sensor). As discussed herein, electrostatic sensor(s) <NUM> detect the total load carried by the uncharged <NUM> and charged particles <NUM>. In non-limiting examples, electrostatic sensor(s) <NUM> may be formed as button sensors with high local resolution, multiple button system sensors arranged in a ring, circumferential ring sensors, and the like. Additionally, or alternatively, electrostatic sensor(s) <NUM> may be staged in flow direction to increase the detectability of charged particles <NUM> dragged by the flow and charged by the matrix of ionizers <NUM> by correlating the signals of the different stages together with the flow speed known from the turbine control system <NUM>.

It is understood that the location(s) and number of electrostatic sensor(s) <NUM> shown in the embodiments is merely illustrative. That is, in the non-limiting example shown in <FIG>, two electrostatic sensors <NUM> are shown. Air filtration assembly <NUM> may include more or less electrostatic sensor(s) <NUM> than those shown in the figures.

During operation of gas turbine system <NUM>, intake air <NUM> may flow through air filtration assembly <NUM> to provide working fluid (e.g., filtered air <NUM>) to compressor <NUM>. Particles <NUM> included in intake air <NUM> may undesirably flow through filtering components (e.g., plurality of vane filters <NUM>, the array of fabric filters <NUM>) due to damage and/or defect in the same components. In air filtration assembly <NUM>, particles <NUM> that are not filtered by the plurality of vane filters <NUM>, and/or the array of fabric filters <NUM> may pass through the matrix of ionizers <NUM> forming electrostatic component <NUM>. The matrix of ionizers <NUM> in turn may charge particles <NUM>. More specifically, each of the plurality of ionizer cells <NUM> forming the matrix of ionizers <NUM> may electrically charge each particle <NUM> that flows therethrough, based on a distinct, predetermined voltage of each of the plurality of ionizer cells <NUM>, as controlled by control system <NUM>. Furthermore, when particle(s) <NUM> pass over and/or pass through one of the plurality of ionizer cells <NUM>, particles <NUM> may alter the breakthrough or breakdown voltage within the corresponding ionizer cell <NUM>, which may also be detectable by control system <NUM>.

As charged particles <NUM> flow out of air filtration assembly <NUM> and are delivered to compressor <NUM> via conduit <NUM>, charged particles <NUM> may be detected by electrostatic sensor(s) <NUM>. Electrostatic sensor(s) <NUM> detect(s) charge particles <NUM> and provide information to control system <NUM> relating to charged particles <NUM>, including, but not limiting to, the amount/concentration of charged particles <NUM>, and/or the associated or corresponding carried load for each detected, charged particle <NUM>. Using this information generated by electrostatic sensor(s) <NUM>, control system <NUM> may determine if the amount and/or the type of uncharged particles <NUM> and charged particles <NUM> included in filtered air <NUM> being provided to compressor <NUM> may damage compressor <NUM> and/or reduce the operational efficiency of gas turbine system <NUM>. In the non-limiting example where, for instance, the concentration and/or amount of charged particles <NUM> could or will damage compressor <NUM>, combustor <NUM>, and/or turbine <NUM>, control system <NUM> may suggest or signal to turbine control system <NUM> that gas turbine system <NUM> should be shut down to prevent damage. The inclusion of air filtration assembly <NUM> with gas turbine system <NUM> allows for early detection of undesirable particles <NUM> flowing to compressor <NUM>, which in turn may prevent or reduce damage to compressor <NUM> by allowing for immediate indication for repair, maintenance, and/or replacement of components of air filtration assembly <NUM>.

In an embodiment, the control system <NUM> integrates an intelligent model <NUM> of fluid flow within the air filtration assembly <NUM> based on data measured by the electrostatic sensor(s) <NUM>. In an embodiment, the data measured by the electrostatic sensor(s) <NUM> includes, but is not limited to, the volume, distribution, and type of particulate entering the compressor <NUM>. The intelligent model <NUM> incorporates known data from a database in the form of the structure of the gas turbine system, the structure of the various fluid flow paths, the location(s) of the electrostatic sensor(s) <NUM>, other known fluid flow data, testing data, and/or field observations to create a customized, specifically-tailored analysis of the fluid flowing through a specific air filtration assembly <NUM> in real time. The intelligent model <NUM> employs equations and/or algorithms to model particle deposition rates, particle fouling rates, and/or compressor degradation rates, etc..

In an embodiment, the controller <NUM>, using the intelligent model <NUM>, is configured to pinpoint probable leak (i.e., particular or debris ingress) locations or areas on the filter inlet housing <NUM>. For example, the intelligent model <NUM> may utilize ambient condition data, particle ingress data/measurements from electrostatic sensors <NUM>, system configuration/layout data, and other known fluid flow data, testing data, field observations, and/or computational fluid dynamic modeling to determine where on the inlet filter housing <NUM> particulate is likely entering, in real time. In an embodiment, the ambient condition data may include, for example, wind speed, wind direction, weather, ambient air particulate concentration, and/or ambient air particulate size. The particle ingress data/measurements may be carried out using a suite of electrostatic sensors positioned at various locations between the inlet <NUM> and compressor <NUM>, and may include, for example, particulate size, particulate concentration, particulate type, location of particulates at various locations along fluid flow path, and/or location of particulates at compressor inlet). In an embodiment, the location along the air flow pathway may be a circumferential location and/or a radial location within the flow pathway. In an embodiment, the location along the air flow pathway may be a circumferential location and/or a radial location at an inlet of the compressor.

<FIG> illustrates an exemplary model <NUM> generated by the intelligent model <NUM> and utilized by the controller <NUM> to determine probable particulate ingress locations <NUM>, <NUM>, <NUM> in the inlet filter housing <NUM>. In an embodiment, the controller <NUM>, using intelligent model, is configured to determine probable particulate ingress locations down to individual weather hood/inlet passages. The intelligent model <NUM> is intended to be only an exemplary manner of determining the probably particulate ingress locations in the inlet duct; it will be appreciated that other systems, devices and methods may also be utilized for determining actual or probable particulate ingress locations without departing from the broader aspects of the invention.

Turning now to <FIG>, a method <NUM> for inhibiting particulate and foreign object ingress using the system of the invention is illustrated. Initially, the controller <NUM> (and/or the intelligent model <NUM>) acquires ambient condition data and particulate ingress data, at steps <NUM> and <NUM>, respectively using techniques that are subject of separate applications but which have been described briefly above. As indicated above, ambient condition data may include, for example, wind speed, wind direction, weather, ambient air particulate concentration, and/or ambient air particulate size. The particle ingress data may be acquired using the suite of electrostatic sensors positioned at various locations between the inlet <NUM> and compressor <NUM>, and may include, for example, particulate size, average particulate size, particulate concentration, average particulate concentration, particulate volume, particulate type, particulate velocity, location of particulates at various locations along fluid flow path, and/or location of particulates at the compressor inlet (i.e., dispersion pattern of the charged particles <NUM>). In an embodiment, the location along the air flow pathway may be a circumferential location and/or a radial location within the flow pathway. In an embodiment, the location along the air flow pathway may be a circumferential location and/or a radial location at an inlet of the compressor.

Using this data, along with testing data and the like, as described above, the controller <NUM>/intelligent model <NUM> determines probable particulate ingress locations at the face of the inlet filter housing <NUM>, at step <NUM>. After determining the particular areas on the inlet filter housing <NUM> where particulate is entering, the controller <NUM> actuates the appropriate relays <NUM> to move the filter screens associated with the particulate ingress locations to the deployed position, at step <NUM>. In this position, the inlet air <NUM> flows through the filter screens <NUM>, which inhibits or prevents the particulate from entering the inlet filter housing <NUM>.

With further reference to <FIG>, in an embodiment, once the selected filter screens <NUM> are deployed at the probable particulate ingress locations, the controller <NUM> acquires updated particulate ingress data, at <NUM>, after a predetermined period of time. This updated particulate ingress data may be acquired utilizing electrostatic sensors in the manner described above. This data can then be compared to the data acquired at step <NUM> to determine if deployment of the filter screens <NUM> at the selected locations was successful at inhibiting the ingress of particulate. If further corrective action is needed, the controller <NUM>, using intelligent model <NUM> in the manner described above, redetermines the probable particulate ingress location(s) at the face of the inlet filter housing <NUM>, based on the updated particulate ingress data, at step <NUM>. Finally, the array of filter screes <NUM> is then adjusted (deploying some and retracting others via relays <NUM>) in dependence upon the redetermined, probable particulate ingress location(s) at the face of the filter housing <NUM>, at step <NUM>. In an embodiment, steps <NUM>, <NUM> and <NUM> may be continuously repeated during system operation. In another embodiment, steps <NUM>, <NUM> and <NUM> may be repeated at predetermined intervals. In yet another embodiment, steps <NUM>, <NUM> and <NUM> may be repeated only if particulate ingress data (e.g., particulate concentration, particulate size, particulate detection location, etc. exceeds a predetermined threshold stored in memory).

While the invention has been described herein as employing electrostatic sensors for detecting particulate and foreign object in the intake airflow, the invention is not intended to be so limited in this regard. In particular, it is contemplated that a variety of systems and methods may be utilized to detect the particulate or foreign objects (including particulate size, type, concentration, etc.) in the intake air flow including, for example, laser based optical sensing systems.

The system and method of the invention, as disclosed above, therefore provides for the selective deployment and retraction of filter screens <NUM> associated with the inlet filter housing <NUM> (and, particularly, with the respective weather hoods <NUM> and air passages thereof) in dependence upon probable particulate ingress locations as determined by the controller <NUM> using intelligent model <NUM>. This is in contrast to existing filter systems for gas turbines where static filters are utilized. The invention described herein therefore allows for only the filter screens required to inhibit particulate ingress to be deployed (while the others are out of the path of airflow), which maximizes airflow to the compressor. By only deploying the filter screens in the areas of the inlet filter housing <NUM> necessary to keep out particulate, the entirety of the airflow into the inlet filter housing <NUM> is not obstructed by the filter screens, which minimizes the pressure drop across the face of the inlet filter housing <NUM> and/or within the filter housing and maximizes system (i.e., gas turbine) performance. This is simply not possible with existing filtration assemblies that use static filters that, due to their inability to be retracted, continuously obstruct airflow even if they are not needed to prevent the ingress of particulate matter at any given time.

In connection with the above, in an embodiment, the controller <NUM> is configured to adjust the position of the filter screens <NUM> within the array in dependence upon a pressure drop (or pressure) within the inlet filter housing <NUM>, in dependence upon a performance or efficiency of the gas turbine <NUM>, and/or in dependence upon a sensing system's output data and computational fluid dynamics (CFD) signatures/patterns. For example, the controller <NUM>, in an embodiment, may balance the need to filter particulate matter at the likely ingress locations with the need to minimize a pressure drop within the inlet filter housing <NUM> so as to maximize engine performance. In particular, in an embodiment, the controller <NUM> may deploy a subset of the filter screens <NUM> by actuating relays <NUM> in order to inhibit or prevent the ingress of particulates. If, however, the pressure drop (or pressure) within the inlet filter housing exceeds or drops below a preset threshold, then the controller <NUM> will adjust the position of the filter screens <NUM> until the pressure or pressure drop comes back within acceptable limits (e.g., by retracting some of the filter screens <NUM>).

While the filter screens <NUM> have been described above as being movable between a retracted position and an extended/deployed position via relays <NUM>, and under control of the controller <NUM>, the invention is not intended to be so limited in this regard. For example, in an embodiment, each filter screen <NUM> may be selectively positioned at a plurality of incremental positions intermediate the retracted position and the deployed position (e.g., a partially deployed position). This allows system performance to be maximized to an even greater degree, and allows for even more precise control of both filtration of particulates and airflow to the compressor. <FIG> depicts the front face of the inlet filter housing <NUM> with the array of weather hoods <NUM> and air passages formed thereby. As disclosed above, each weather hood <NUM> and air passage may have and associated or dedicated filter screen <NUM> (and actuator and relay <NUM>), forming an array or matrix of filter screens <NUM> configured to remove particulates from the inlet airflow <NUM>.

As indicated, in an embodiment, and depending upon the determination of probable area(s) of particulate ingress, the controller <NUM> is configured to position each of the filter screens <NUM> in either a deployed/extended position where it is placed entirely or substantially entirely across the air passage, a partially deployed position where it extends only partially into the air flow <NUM> (but some portion of the air flow is permitted to bypass the filter screen <NUM>), or a retracted position where all of the air flow through the passage is permitted to bypass the filter screen. For example, as shown in <FIG>, the controller <NUM>, using intelligent model <NUM> may determine that the primary location of particulate ingress is occurring at the upper left quadrant on the front face of the inlet filter housing <NUM>, with the highest concentration of particulate entering through the extreme upper left of the inlet filter housing <NUM>, with a lesser concentration moving down and to the right. In response to this determination, the controller <NUM> may fully deploy the filter screens <NUM> in the upper left quadrant (denoted by the letter D), and partially deploy the filter screens <NUM> on the outer boundary of the high particulate concentration ingress area (denoted by the letter P), and maintain (or retract) the filter screens <NUM> in all other matrix locations (denoted by the letter X). As indicated above, deploying only the filter screens necessary to stop particulate ingress minimizes the pressure drop across the face of the inlet filter housing <NUM>, maximizes airflow to the compressor <NUM>, and therefore optimizes overall system performance heretofore not possible in the art.

Moreover, while the filter screens <NUM> have been disclosed herein as being positioned adjacent to the front face of the inlet filter housing <NUM> at inlet <NUM>, the invention is not intended to be so limited in this regard. In particular, in an embodiment, the array of filter screens <NUM> may be positioned at any location along the air flow passage/inlet duct <NUM> between the inlet <NUM> and the outlet <NUM> or between the inlet <NUM> of the inlet filter housing <NUM> and the inlet of the compressor <NUM>. In yet other embodiments, the system may include a plurality of layers or matrices of filter screens. For example, the system may include a first array or matrix of filter screens located at the inlet <NUM> and one or more arrays of filter screens downstream from the inlet <NUM>. Such a configuration would allow for an even greater level of control over particulate ingress, pressure drop and overall system performance.

The system and method of the invention, as described herein, are particularly suitable for use in areas where extreme weather may generate a high concentration of particulate matter or foreign object debris in the intake airflow. Such area may include arid or desert regions where sandstorms or high dust conditions are common, and/or in marine or coastal environments where there is a lot of moisture in the intake air. As disclosed above, when severe climatic conditions such as sandstorm, dusty or high-moisture conditions are detected, the control system actuates the electrical switch/relay/valve to deploy or close a series of mesh filter screens to avoid, or stop, a large influx of dust or particulate. When conditions normalize, the actuator is commanded to open or retract the filter screens to prevent or alleviate any additional pressure drop. The invention thus is capable reducing particulate and/or foreign object ingress related events in a gas turbine system, and therefore reduces the cost of maintaining gas turbine system components.

Finally, the system <NUM> may include the necessary electronics, software, memory, storage, databases, firmware, logic/state machines, microprocessors, communication links, displays or other visual or audio user interfaces, printing devices, and any other input/output interfaces to perform the functions described herein and/or to achieve the results described herein, which may be in real-time. For example, the system <NUM> may include at least one processor and system memory / data storage structures, which may include random access memory (RAM) and read-only memory (ROM). The at least one processor of the system <NUM> may include one or more conventional microprocessors and one or more supplementary co-processors such as math co-processors or the like. The data storage structures discussed herein may include an appropriate combination of magnetic, optical and/or semiconductor memory, and may include, for example, RAM, ROM, flash drive, an optical disc such as a compact disc and/or a hard disk or drive.

Additionally, a software application that adapts the controller to perform the methods disclosed herein may be read into a main memory of the at least one processor from a computer-readable medium. The term "computer-readable medium", as used herein, refers to any medium that provides or participates in providing instructions to the at least one processor of the system <NUM> (or any other processor of a device described herein) for execution. Such a medium may take many forms, including but not limited to, non-volatile media and volatile media. Non-volatile media include, for example, optical, magnetic, or opto-magnetic disks, such as memory. Volatile media include dynamic random-access memory (DRAM), which typically constitutes the main memory. Common forms of computer-readable media include, for example, a flexible disk, hard disk, magnetic tape, any other magnetic medium, a CD-ROM, DVD, any other optical medium, a RAM, a PROM, an EPROM or EEPROM (electronically erasable programmable read-only memory), a FLASH-EEPROM, any other memory chip or cartridge, or any other medium from which a computer can read.

While in embodiments, the execution of sequences of instructions in a software application causes at least one processor to perform the methods/processes described herein, hard-wired circuitry may be used in place of, or in combination with, software instructions for implementation of the methods/processes of the present invention. Therefore, embodiments of the present invention are not limited to any specific combination of hardware and/or software.

This written description uses examples to disclose several embodiments of the invention, including the best mode, and also to enable one of ordinary skill in the art to practice the embodiments of invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to one of ordinary skill in the art.

Since certain changes may be made in the above-described system and method without departing from the scope of the invention herein involved, it is intended that all of the subject matter of the above description or shown in the accompanying drawings shall be interpreted merely as examples illustrating the inventive concept herein and shall not be construed as limiting the invention.

A turbine system, comprising a turbine having a compressor for compressing intake air, and an inlet filter housing in fluid communication with the compressor and having an array of air passages for ingress of the intake air, the inlet filter housing being configured to remove particulates from the intake air prior to passage of the intake air to the compressor. The inlet filter housing includes an array of air passages for receiving the intake air therethrough, and an array of filter screens generally corresponding to the array of air passages. The array of filter screens are individually movable between a retracted position where the intake air is permitted to bypass a respective filter screen, and a deployed position where the intake air passes through the filter screen. When in the deployed position the filter screens are configured to remove the particulates from the intake air.

The turbine system the preceding clause, wherein the array of filter screens are individually positionable at a plurality of incremental positions intermediate the retracted position and the deployed position.

The turbine system of any one of the preceding clauses, wherein the system further includes a controller configured to determine a probable location of particulate ingress at the filter housing in dependence upon at least one of particulate ingress data acquired by sensors of the turbine system and/or ambient condition data of the ambient air outside the inlet filter housing, and to control a position of at least one filter screen in the array of filter screens.

The turbine system of any one of the preceding clauses, wherein the particulate ingress data includes at least one of particulate size, particulate concentration, particulate type, and/or location of particulate along an air flow pathway, and wherein the ambient condition data includes at least one of wind speed, wind direction, weather, ambient air particulate concentration, and/or ambient air particulate size.

The turbine system of any one of the preceding clauses, wherein the filter screens are mesh filter screens having an anti-rebounding coating.

The turbine system of any one of the preceding clauses, wherein the controller is further configured to acquire updated particulate ingress data, and redetermine the probable particulate ingress location on the air inlet of the combustion system in dependence upon the updated particulate ingress data.

The turbine system of any one of the preceding clauses, wherein the controller is further configured to adjust a position of at least one filter screen of the array of filter screens in dependence upon the redetermined probable particulate ingress location.

A method for inhibiting particulate ingress in a combustion system comprises the steps of providing an inlet duct in fluid communication with a turbine having a compressor, the inlet duct having an intake area for a flow of intake air, determining at least one location of particulate or foreign object ingress along the intake area, and moving a first subset of filter screens of an array of filter screens so as to extend across the flow of intake air at the location of particulate or foreign object ingress.

The method according to the preceding clause, wherein the step of determining the at least one location of particulate or foreign object ingress includes sensing or measuring at least a concentration and/or distribution of particulates or foreign objects at an inlet of the compressor.

The method according to any one of the preceding clauses, wherein the method further includes the step of adjusting a position of a plurality of filter screens in the array of filter screens in dependence upon a pressure within the inlet duct and/or turbine performance.

This written description uses examples to disclose several embodiments of the invention, including the best mode, and also to enable one of ordinary skill in the art to practice the embodiments of invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to one of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claim 1:
A method (<NUM>) for inhibiting particulate ingress in a combustion system, comprising the steps of:
acquiring particulate ingress data in an air flow pathway (<NUM>) of the combustion system, the particulate ingress data representative of particles (<NUM>) in the air flow pathway (<NUM>) charged by an electrostatic component (<NUM>) including a matrix of ionizers (<NUM>) and particles (<NUM>) in the air flow pathway (<NUM>) uncharged by the electrostatic component (<NUM>);
determining a probable particulate ingress location (<NUM>) on an air inlet (<NUM>) of the combustion system (<NUM>) in dependence upon the charged particles (<NUM>) and the uncharged particles (<NUM>) in the particulate ingress data; and
deploying a filter screen (<NUM>) at the determined probable particulate ingress location (<NUM>) to inhibit particulate ingress at the determined probable particulate ingress location (<NUM>).