Patent Description:
Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modem wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and one or more rotor blades. The nacelle includes a rotor assembly coupled to the gearbox and to the generator. The rotor assembly and the gearbox are mounted on a bedplate support frame located within the nacelle. More specifically, in many wind turbines, the gearbox is mounted to the bedplate via one or more torque arms or arms. The one or more rotor blades capture kinetic energy of wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy the electrical energy may be transmitted to a converter and/or a transformer housed within the tower and subsequently deployed to a utility grid.

Many of the components of a wind turbine have a tendency to generate heat and therefore, must be cooled. One method for cooling the components is using airflow. In order to achieve such cooling, air must be able to enter the tower in a sufficient quantity, with the same quantity of air being able to exit the tower. A significant portion of air used for cooling in conventional wind turbines is introduced through the tower door. Due to structural concerns, it is generally undesirable to form additional openings in the tower. As such, the amount of air available for cooling the wind turbine is normally limited by the surface area of the tower door.

In addition, in order to minimize ingestion of undesirable contaminants (e.g., sand, debris, etc.), a filter is often integral to the door. As such, the filter is designed to entrap contaminants while permitting a portion of the air to pass through. In order to prevent unauthorized entry into the tower, these filters are often covered with louvers or grates. The combination of the entry barriers and the filter results in a pressure drop for the air entering the tower that is typically between <NUM> Pa and <NUM> Pa. The pressure drop, in combination with the limits imposed by the size of the door, may result in a restricted airflow that is insufficient to provide the desired level of cooling for the wind turbine. <CIT> describes a cooling system of a wind turbine and a wind tubine. <CIT> describes a unit cooling system for wind turbines, a control method for the overall unit cooling system, and a wind turbine. <CIT> describes a wind turbine generator.

Thus, the art is continuously seeking new and improved systems and methods for increasing the quantity of filtered air available for cooling in the wind turbine. Accordingly, a system and method for cooling a tower of a wind turbine that addresses the aforementioned issues would be advantageous.

In one aspect, the present disclosure is directed to a system according to claim <NUM> for cooling a tower of a wind turbine. The system includes at least one cooling fluid inlet for receiving a cooling fluid into the tower. The at least one cooling fluid inlet is arranged in a tower wall of the tower of the wind turbine, the at least one cooling fluid inlet comprising at least one opening defined by a tower door and an intake plenum coupled to an inner face of the tower door and surrounding the at least one opening defined by the tower door. The system includes at least one platform positioned within the tower at a predetermined height above a foundation of the wind turbine, configured to create a space within the tower between the platform and the foundation to provide a location for the installation of a filtration assembly. The system includes a filtration assembly arranged within the tower. The filtration assembly includes a plurality of flow guiding structures that define a plurality of flow paths for providing a plurality of flow direction changes and/or flow velocity changes to the cooling fluid. Additionally, the system includes at least one cooling fluid outlet for directing the filtered cooling fluid within the tower. The system defines that the filtration assembly is positioned between the at least one platform and the foundation of the wind turbine and that the plurality of flow guiding structures define a plurality of <NUM>-degree turns for the cooling fluid configured to slow the cooling fluid and configured to allow one or more particles in the cooling fluid to settle out.

In an embodiment, the cooling fluid inlet(s) may be set within at least one of a tower door or a tower door frame of the tower.

In an embodiment, one or more of the plurality of flow guiding structures may be integral with at least one platform positioned within the tower at a predetermined height above a foundation of the wind turbine. Also, in an embodiment, the plurality of flow guiding structures may be positioned between the platform(s) and the foundation. In an additional embodiment, the plurality of flow paths may direct the cooling fluid entering the cooling fluid inlet(s) towards the foundation through the platform(s) and/or to at least one side of the platform(s).

In a further embodiment, the system may include a tower filtration assembly positioned between the platform(s) and a nacelle of the wind turbine. The tower filtration assembly may be in fluid communication with the cooling fluid outlet(s). The tower filtration assembly may include at least one of a filter element or the plurality of flow guiding structures.

In an embodiment, the plurality of flow guiding structures may define a plurality of <NUM>-degree turns for the cooling fluid.

In an embodiment, the filtration assembly may include at least one of a filter element or particle separation element for further filtering the cooling fluid as the cooling fluid flows through the plurality of flow guiding structures and/or exits the cooling fluid outlet(s).

In an additional embodiment, the system may include a maintenance location arranged adjacent to one or more of the plurality of flow guiding structures. The maintenance location may provide access to the plurality of flow guiding structures such that the filtration assembly can be cleaned and/or replaced. In a further embodiment, the maintenance location may be an access door integral with at least one of a vertical side of the filter assembly or the at least one platform.

In an embodiment, the system may also include at least one flow sensor in fluid communication with the cooling fluid inlet(s) and/or the cooling fluid outlet(s) so as to monitor a flow rate of the cooling fluid.

In a further embodiment, the system may include at least one of a blower or a fan positioned within the tower and oriented so as to increase a flow of the cooling fluid through the plurality of flow guiding structures.

In another aspect, the present disclosure is directed to a method according to claim <NUM> for cooling a tower of a wind turbine. The method includes receiving cooling fluid through at least one cooling fluid inlet and into the tower. The method also includes directing the cooling fluid through a filtration assembly within the tower. The filtration assembly includes a plurality of flow guiding structures that define a plurality of flow paths for providing a plurality of flow direction changes and/or flow velocity changes to the cooling fluid. Additionally, the method includes directing the filtered cooling fluid through at least one cooling fluid outlet so as to cool one or more wind turbine components within the tower. Moreover, the method includes that the at least one cooling fluid inlet comprises at least one opening defined by a tower door and an intake plenum coupled to an inner face of the tower door and surrounding the at least one opening defined by the tower door.

According to the invention, directing the cooling fluid through the filtration assembly includes directing the cooling fluid through at least one flow guiding structure of the plurality flow guiding structures that is integral with at least one platform positioned within the tower a predetermined height above the foundation of the wind turbine. In an additional embodiment, directing the cooling fluid through the filtration assembly within the tower may include directing the cooling fluid towards the foundation through the platform(s) and/or to at least one side of the platform(s). The method further includes that the at least one platform is configured to create a space within the tower between the platform and the foundation to provide a location for the installation of the filtration assembly. The method also includes that the filtration assembly is positioned between the at least one platform and the foundation of the wind turbine. Moreover, directing the cooling fluid through the filtration assembly further comprises directing the cooling fluid through a plurality of <NUM>-degree turns defined by the plurality of flow guiding structures so as to slow the cooling fluid and allow one or more particles in the cooling fluid to settle out. It should be further understood that the method may include any of the additional steps and/or features described herein.

In another aspect, the present disclosure is directed to a wind turbine. The wind turbine may include a tower secured atop a foundation, a nacelle mounted atop the tower, a rotor mounted to the nacelle, and at least one platform positioned within the tower at a predetermined height above the foundation. The wind turbine may also include a cooling system positioned within the tower. The cooling system may include at least one cooling fluid inlet arranged in a wall of the tower of the wind turbine. The cooling system may also include a filtration assembly in fluid communication with the cooling fluid inlet(s) and positioned between the platform and the foundation. The filtration assembly may include a plurality of flow guiding structures that define a plurality of flow paths for providing a plurality of flow direction changes and/or flow velocity changes to the cooling fluid. Additionally, the cooling system may include at least one cooling fluid outlet in fluid communication with the filtration assembly and positioned so as to direct the filtered cooling fluid within the tower.

As used herein, the terms "upstream" and "downstream" are used in reference to the direction of the flow of a cooling fluid from a point of entry into the wind turbine to a point of exit from the wind turbine.

Generally, the present disclosure is directed to a system and method for cooling a tower of a wind turbine. The system may include a cooling fluid inlet arranged in a wall of a tower of the wind turbine. Cooling fluid (e.g., unfiltered, ambient air) may be received by the cooling fluid inlet and brought into the tower. The cooling fluid may be directed to a filtration assembly arranged within the tower. The filtration assembly may have any number of flow guiding structures that define a desired number of flow paths for the cooling fluid. The number of flow paths may provide a plurality of flow direction changes and/or flow velocity changes to the cooling fluid. With each direction and/or flow velocity change, a portion of particles may settle out of the cooling fluid flow. As a result, the cooling fluid may exit the filtration assembly as filtered cooling fluid (e.g., filtered, ambient air). The filtered cooling fluid may be directed through a cooling fluid outlet also located within the tower, to cool the interior of the tower.

Referring now to the drawings, <FIG> illustrates a perspective view of one embodiment of a wind turbine <NUM> according to the present disclosure. As shown, the wind turbine <NUM> generally includes a tower <NUM> extending from a support surface <NUM>, a nacelle <NUM> mounted on the tower <NUM>, and a rotor <NUM> coupled to the nacelle <NUM>. The rotor <NUM> includes a rotatable hub <NUM> and at least one rotor blade <NUM> coupled to and extending outwardly from the hub <NUM>. For example, in the illustrated embodiment, the rotor <NUM> includes three rotor blades <NUM>. However, in an alternative embodiment, the rotor <NUM> may include more or less than three rotor blades <NUM>. Each rotor blade <NUM> may be spaced about the hub <NUM> to facilitate rotating the rotor <NUM> to enable kinetic energy to be transferred from the wind into usable mechanical energy, and subsequently, electrical energy. For instance, the hub <NUM> may be rotatably coupled to an electric generator (not shown) positioned within the nacelle <NUM> to permit electrical energy to be produced.

Access to the interior of the wind turbine <NUM> may be provided through an entryway <NUM> defined by the tower wall <NUM> of the tower <NUM>. Further, as shown, the entryway <NUM> may be positioned between the support surface <NUM> and the nacelle <NUM>. Moreover, as shown, the entryway <NUM> may include a tower door <NUM> set within a tower door frame <NUM>. In an embodiment, a threshold <NUM> of the tower door <NUM>, and the corresponding opening of the door frame <NUM>, may be essentially flat and parallel with a horizontal plane to facilitate passage into and out of the wind turbine <NUM>.

In addition, as shown, an entry landing <NUM> may be coupled exterior to the tower wall <NUM>. The entry landing <NUM> may intersect the tower door frame <NUM> at a location between the threshold <NUM> and the support surface <NUM>. The tower door frame <NUM> may have a first tower door frame portion <NUM> positioned above the entry landing <NUM>, and a second tower door frame portion <NUM> positioned below the entry landing <NUM>. Access to the entry landing <NUM> may be provided by at least one staircase <NUM> coupled between the support surface <NUM> and the entry landing <NUM>.

Referring now to <FIG>, a simplified schematic view of one embodiment of a cooling system <NUM> according to the present disclosure is illustrated. As shown, the cooling system <NUM> may include at least one cooling fluid inlet <NUM> for receiving a cooling fluid (CU). In an embodiment, the cooling fluid (CU) may be a portion of unfiltered ambient air drawn from the surroundings. In such embodiments, the cooling fluid (CU) drawn from the ambient air may include a quantity of undesirable contaminants, such as sand or other particulate matter suspended in the flow.

In an embodiment, the flow of the cooling fluid (CU) may be directed within the tower <NUM> by a plurality of flow guiding structures <NUM>. The flow guiding structures <NUM> may include a plurality of plenums or ducts configured to direct the cooling fluid (CU). For example, in an embodiment, a tower filtration duct <NUM> may fluidly couple the cooling fluid inlet <NUM> to at least one cooling fluid outlet <NUM> within the tower <NUM>.

Still referring to <FIG>, in an embodiment, the cooling system <NUM> may include a filtration assembly <NUM> arranged within the tower <NUM>. As such, the filtration assembly <NUM> may be configured to remove contaminants from the cooling fluid (CU) and develop a filtered cooling fluid (CF). The amount of particulates to be removed from the cooling fluid (CU) may be determined by the level of particulate contamination in the ambient air and the magnitude of the airflow required to achieve the desired cooling effects within the tower <NUM>.

For example, if the wind turbine <NUM> were to be sited in a desert environment having a high quantity of airborne dust, the level of filtration required by the filtration assembly <NUM> may be greater than for a wind turbine <NUM> sited offshore. Additionally, the filtration assembly <NUM> may be configured to develop the filtered cooling fluid (CF) while minimizing a pressure drop for a given flow rate of the cooling fluid (CU, CF) across the filter assembly. For example, in an embodiment, the filtration assembly <NUM> may cause a drop in the flow rate of the cooling fluid (CU) which is less than <NUM> Pa (e.g., <NUM>-<NUM> Pa, <NUM>-<NUM> Pa, or <NUM> to less than <NUM> Pa).

In an embodiment, such as depicted in <FIG>, the cooling system <NUM> may also include a tower filtration assembly <NUM>, which will be discussed in more detail below. The tower filtration assembly <NUM> may be fluidly coupled by a tower filtration duct <NUM> between the cooling fluid inlet <NUM> and the cooling fluid outlet <NUM>. The tower filtration assembly <NUM> may be configured to operate in conjunction with, or independently of, the filtration assembly <NUM> to provide a filtered cooling flow (CF) to the turbine tower <NUM>.

Referring now to <FIG>, a front view of one embodiment of the at least one cooling fluid inlet <NUM> is depicted according to the present disclosure. In at least one embodiment, the cooling fluid inlet <NUM> may be set within at least one of the tower door <NUM> and/or the tower door frame <NUM> of the tower <NUM>.

In an embodiment, the cooling fluid inlet <NUM> may include at least one opening <NUM> defined by the tower door <NUM>. More specifically, as shown, the cooling fluid inlet <NUM> includes a plurality of openings <NUM>. In other embodiments, the cooling fluid inlet <NUM> may include a single opening having a large area, a plurality of smaller openings having a smaller area, or combinations thereof. For example, as is depicted in <FIG>, a single, large opening may be defined by an upper portion <NUM> of the tower door <NUM>, and a lower portion <NUM> of the door <NUM> may be divided into a plurality of smaller openings. It should be appreciated that a single, large opening may maximize the area through which cooling fluid (CU) may be drawn, while a plurality of smaller openings may serve as a barrier to an unauthorized entry into the tower <NUM>.

In at least one embodiment, the opening(s) <NUM> may be partially obstructed by an entry barrier <NUM>. The entry barrier <NUM> may be configured to resist the entry of a human or wildlife into the tower <NUM>. For example, the entry barrier <NUM> may be a screen or grate coupled to the tower door <NUM>. The screen or grate may be particularly well suited when other barriers to entry, such as a limited opening size, are present.

In an additional embodiment, the entry barrier <NUM> may be a plurality of louvers or bars coupled to the tower door <NUM>. It may be desirable to install a plurality of louvers or bars when other barriers to entry are not present and a need for increased security may exist. For example, in an embodiment wherein a single, large opening is defined by the tower door <NUM>, a screen or grate may be inadequate to prevent the forcible entry of a human into the tower <NUM>. It should, however, be appreciated that a plurality of louvers having sufficient structure to resist the forcible entry of a human, may reduce the effective surface area of the opening(s) <NUM>.

In at least one embodiment, as shown in <FIG> and <FIG>, the cooling fluid inlet(s) <NUM> may also include an intake plenum <NUM> coupled to an inner face <NUM> (<FIG>) of the tower door <NUM>. As shown particularly in <FIG>, the intake plenum <NUM> may be positioned to surround the opening <NUM> and may be a flow guiding structure <NUM>. In an exemplary embodiment, the intake plenum <NUM> may form a solid barrier to a forcible entry into the tower <NUM> and may serve as an augmentation of the entry barrier <NUM>. For example, the intake plenum <NUM> may be formed from sheet-metal or a composite sheet. It should be appreciated that the utilization of the intake plenum <NUM> may reduce the need for other extensive barriers to the forcible entry of a human, such as a plurality of louvers or bars, or reducing the surface area of the opening <NUM>. In an embodiment including the intake plenum <NUM>, a screen or grate may be included so as to prevent animal entry into the tower <NUM>.

Still referring to <FIG>, in an embodiment, the cooling fluid inlet(s) <NUM> may also include a frame opening <NUM> defined by the door frame <NUM>. In an embodiment, the frame opening <NUM> may be defined in the second tower door frame portion <NUM>. As such, the frame opening <NUM> may be disposed between the entry landing <NUM> and the support surface <NUM>. Similar to the opening(s) <NUM> of the tower door <NUM>, the frame opening <NUM> may be partially obstructed by the entry barrier <NUM>. It should be appreciated that the frame opening <NUM> may also be located in the first tower door frame portion <NUM> (in addition to the second tower door frame portion <NUM>). Alternatively, a plurality of door frame openings <NUM> may be disposed at various locations defined by the tower door frame <NUM>.

Referring to <FIG> and <FIG>, the system <NUM> may also include a filtration assembly <NUM> arranged within the tower <NUM>. The filtration assembly <NUM> may include a plurality of flow guiding structures <NUM>. Further, the flow guiding structures <NUM> may define a plurality of flow paths for providing a plurality of flow direction changes and/or flow velocity changes to the cooling fluid (CU).

In an embodiment, such as depicted in <FIG>, the plurality of flow guiding structures <NUM> may define a tortured path for the cooling fluid (CU). For example, in at least one embodiment, the plurality of flow guiding structures <NUM> may define a plurality of <NUM>-degree turns (A) for the cooling fluid (CU). In such an embodiment, the plurality of flow direction changes may result in a deceleration of the cooling fluid (CU). As the cooling fluid (CU) flows through the various flow direction changes, the energy of the cooling flow may decrease to a point where the cooling flow is no longer able to support a portion of the particulate matter contained therein and at least portions of the particulate matter may settle out of the cooling fluid. In particular, as the cooling fluid (CU) changes direction, the decelerating cooling fluid (CU) may lack the necessary energy to overcome the inertia of the particulate matter. As a result, a portion of the particular matter may depart the flow of the cooling fluid (CU) by continuing along its previous path as the cooling fluid (CU) changes direction. It should be appreciated that the number flow direction changes and/or flow velocity changes may be varied in order to achieve a desired level of particulate separation, or filtration. It should be further appreciated that with a greater number of flow direction changes and/or flow velocity changes, may come a higher degree of particle removal from the filtered cooling fluid (CF).

Still referring to <FIG>, in certain embodiments, it may be desirable to further control the quality of the filtered cooling fluid (CF). In such an embodiment, the amount of particulate matter removed from the cooling fluid (CU) may be increased by the inclusion of a filter element <NUM> upstream of the cooling fluid outlet(s) <NUM>. The filter element <NUM> may be a synthetic or natural mesh filter media. It should be appreciated that the filter element <NUM> may include any number of filter elements <NUM>. For example, a plurality of filter elements <NUM> may be disposed at various locations along the tortured path of the filtration assembly <NUM>. Alternatively, in an embodiment, the number flow direction changes and/or flow velocity changes may be reduced and the number of filter elements <NUM> may be increased so that the filtration assembly <NUM> may include more filter elements <NUM> than flow guiding structures <NUM>.

In an additional embodiment, the filtration assembly <NUM> may also include at least one particle separation element <NUM>. The particle separation element <NUM> may be positioned in fluid contact with the flow paths defined by the flow guiding structures <NUM>. The particle separation element <NUM> may be oriented so that the inertia of a portion of the particulate matter carried by the cooling fluid (CU) may carry the portion of the particular matter into the particle separation element <NUM>. As such, the particle separation element <NUM> may form a scavenge plenum disposed within the filtration assembly <NUM>.

Still referring to <FIG>, one or more of the plurality of flow guiding structures <NUM> may, in an embodiment, be integral with at least one platform <NUM> positioned within the tower <NUM>. In an embodiment, the platform <NUM> may be a platform that supports equipment and/or facilitates human entry. For example, the platform <NUM> may be a down tower assembly (DTA) platform supporting various DTA components <NUM> (e.g., a converter and/or a transformer). Thus, the platform <NUM> may be positioned a predetermined height (H) above a foundation <NUM> of the wind turbine <NUM>. It should be appreciated that positioning the platform <NUM> the predetermined height (H) above the foundation <NUM> may create a space within the tower <NUM> between the platform <NUM> and the foundation <NUM> that may be free of DTA components <NUM>. This space between the platform <NUM> and the foundation <NUM> may provide a convenient location for the installation of additional equipment, such as the filtration assembly <NUM>. It should be appreciated that the space between the platform <NUM> and the foundation <NUM> may enable an increase in an effective filter area of the filtration assembly <NUM>. The increase in the effective filter area of the filtration assembly <NUM> may reduce pressure drop and increase airflow through the tower <NUM> relative to the pressure drop in airflow through a conventional, door-installed filter.

In another embodiment, such as depicted in <FIG>, the filtration assembly <NUM>, including the corresponding flow guiding structures <NUM>, may be positioned between the platform <NUM> and the foundation <NUM>. In an alternative embodiment, the filtration assembly <NUM> may be positioned between the platform(s) <NUM> and the nacelle <NUM>. For example, in at least one embodiment, the filtration assembly <NUM> may be formed so as to have an annular structure conforming to the geometry of the tower wall <NUM>.

In an embodiment, the flow guiding structures <NUM> may establish a plurality of flow paths which direct the cooling fluid (CU) entering the cooling fluid inlet(s) <NUM> towards the foundation, through the at least one platform <NUM> and/or to at least one side of the at least one platform <NUM>. For example, in at least one embodiment, the intake plenum <NUM> may be fluidly coupled to a platform passage <NUM> defined by the platform <NUM>. The platform passage <NUM> may be a permeable portion of the platform <NUM> (e.g., a grate, a vent, or a series of perforations) positioned adjacent to the threshold <NUM> of tower door frame <NUM>. The platform passage <NUM> may be fluidly coupled to an additional flow guiding structure <NUM> positioned between the foundation <NUM> and the platform <NUM>. In an additional embodiment, the intake plenum <NUM> may be fluidly coupled to an additional flow guiding structure <NUM> positioned perpendicular to the threshold <NUM>. In yet another embodiment, more than one intake plenum <NUM> may be coupled to the tower door <NUM>, with at least one intake plenum <NUM> being fluidly coupled to the platform passage <NUM>, while at least one additional intake plenum <NUM> being coupled to an additional flow guiding structure <NUM> positioned adjacent to the tower door <NUM>.

It should be appreciated that the fluid coupling of the cooling fluid inlet(s) <NUM> to the corresponding flow guiding structures <NUM> may require a temporary seal <NUM> (<FIG>). For example, the intake plenum <NUM> may be temporarily sealed to the platform passage <NUM> whenever the tower door <NUM> is in a closed position. In an embodiment, the seal <NUM> may be a loose-fit seal. For example, the seal <NUM> may include a curtain or bristles coupled to the intake plenum <NUM>. Alternatively, the seal <NUM> may be a spring-loaded or magnetic seal, which may retract into the platform <NUM> or the intake plenum <NUM> whenever the tower door <NUM> is transitioned from a closed state to an open state.

Referring still to <FIG>, in an additional embodiment, the cooling system <NUM> may also include a maintenance location <NUM> arranged adjacent to one or more of the plurality of flow guiding structures <NUM>. Thus, the maintenance location <NUM> may permit access to the filtration assembly <NUM> so that the filtration assembly <NUM>, or components thereof, may be inspected, cleaned, serviced, repaired, or replaced. In at least one embodiment, the maintenance location <NUM> may be an access door or hatch integral with the platform <NUM>. In an additional embodiment, the maintenance location <NUM> may be an access door or hatch integral with a vertical side <NUM> of the filtration assembly <NUM>.

Additionally, as shown, the filtration assembly <NUM> may include at least one cleanout tray <NUM>. The cleanout tray <NUM> may be positioned within the filtration assembly <NUM> at a location where the particulate matter may accumulate. Accordingly, the cleanout tray <NUM> may be configured to be extracted from the filtration assembly <NUM> in order to facilitate the removal of the particulate accumulation.

Referring still to <FIG>, in one embodiment, the cooling system <NUM> may also include at least one flow sensor <NUM> in fluid communication with the cooling fluid inlet(s) <NUM> and/or the cooling fluid outlet(s) <NUM>. The flow sensor <NUM> may facilitate monitoring of a flow rate of the cooling fluid (CU). For example, in an embodiment, a first flow sensor <NUM> may be fluidly coupled to the cooling fluid inlet(s) <NUM>. A second flow sensor <NUM> may be fluidly coupled to the cooling fluid outlet(s) <NUM>. In such embodiments, the outputs of the first and second flow sensors <NUM>, <NUM> may be compared to determine a reduction in a cooling fluid (CU) flow through the filtration assembly <NUM>. A baseline pressure differential may be known or measured for an unobstructed filtration assembly <NUM> (e.g. a filtration assembly without clogs or obstructions). As such, an increase in the measured pressure differential may indicate a clogged filter element, excessive particulate accumulation, or other obstruction in the cooling system <NUM>, and thus, a need for a maintenance procedure to be performed on the cooling system <NUM>.

In yet another embodiment, the cooling system <NUM> may also include a blower or a fan <NUM> positioned within the tower <NUM>. The blower or fan <NUM> may be oriented so as to increase the flow the cooling fluid (CU) through the plurality of flow guiding structures <NUM>. It should be appreciated that the fan or blower <NUM> may augment a naturally occurring chimney effect within the tower <NUM>. This augmentation of the chimney effect by the fan or blower <NUM> may, at least partially, compensate for a reduction in flow pressure of the cooling fluid (CU) due to filter elements <NUM>, or other obstructions in the cooling system <NUM>.

Referring still to <FIG>, and also back to <FIG>, the cooling system <NUM> may, as mentioned previously, also include the tower filtration assembly <NUM>. The tower filtration assembly <NUM> may be positioned between the platform(s) <NUM> and the nacelle <NUM>. In addition, the tower filtration assembly <NUM> may be in fluid communication with the cooling fluid outlet(s) <NUM>. The tower filtration assembly <NUM> may include a tower filter element <NUM>. In an embodiment, the tower filter element <NUM> may be a synthetic or natural mesh filter media.

Like the filtration assembly <NUM>, the tower filtration assembly <NUM> may also include a plurality of flow guiding structures <NUM> positioned so as to provide a number flow direction changes and/or flow velocity changes to a cooling fluid (CU) flow. Alternatively, the tower filtration assembly <NUM> may include both the tower filter element <NUM> and the plurality of flow guiding structures <NUM>. In at least one embodiment, the tower filtration assembly <NUM> may be coupled to the inner face <NUM> of the tower door <NUM>. In an embodiment, the tower filtration assembly <NUM>, including the tower filter element <NUM>, may be coupled to the upper portion <NUM> of the tower door <NUM>, while the filtration assembly <NUM> may be fluidly coupled to the lower portion <NUM> of the tower door <NUM>. It should be appreciated that in such a configuration, the flow of filtered cooling fluid (CF) exiting the tower filtration assembly <NUM> may augment the flow of filtered cooling fluid (CF) exiting the filtration assembly <NUM>. Alternatively, the tower filtration assembly <NUM> may be positioned in proximity with the nacelle <NUM> so that the flow of filtered cooling fluid (CF) exiting the tower filtration assembly <NUM> may be primarily directed to providing additional filtered cooling fluid (CF) to the nacelle <NUM>.

Referring to <FIG>, a flow diagram of one embodiment of a method <NUM> for cooling a tower of a wind turbine is illustrated. The method <NUM> may be implemented using, for instance, the cooling system <NUM> discussed above with references to <FIG>. <FIG> depicts steps performed in a particular order for purposes of illustration and discussion. Those of ordinary skill in the art, using the disclosures provided herein, will understand that various steps of the method <NUM>, or any of the methods disclosed herein, may be adapted, modified, rearranged, performed simultaneously, or modified in various ways without deviating from the scope of the present disclosure.

As shown at (<NUM>), the method <NUM> may include receiving cooling fluid through at least one cooling fluid inlet and into the tower. As shown at (<NUM>), the method <NUM> may include directing the cooling fluid through a filtration assembly within the tower. The filtration assembly may include a plurality of flow guiding structures that define a plurality of flow paths for providing a plurality of flow direction changes and/or flow velocity changes to the cooling fluid. Additionally, as shown at (<NUM>), the method <NUM> may include directing the filtered cooling fluid through at least one cooling fluid outlet so as to cool one or more wind turbine components within the tower.

In additional embodiments, the method <NUM> may also, in accordance with the present disclosure, include directing the cooling fluid through a plurality of <NUM>-turns defined by the plurality of flow guiding structures so as to slow the cooling fluid and allow one or more particles in the cooling fluid to settle out.

Furthermore, the skilled artisan will recognize the interchangeability of various features from different embodiments. Similarly, the various method steps and features described, as well as other known equivalents for each such methods and feature, can be mixed and matched by one of ordinary skill in this art to construct additional systems and techniques in accordance with principles of this disclosure. Of course, it is to be understood that not necessarily all such objects or advantages described above may be achieved in accordance with any particular embodiment. Thus, for example, those skilled in the art will recognize that the systems and techniques described herein may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein.

Claim 1:
A system for cooling a tower of a wind turbine, the system comprising:
the tower of the wind turbine,
at least one cooling fluid inlet (<NUM>) for receiving a cooling fluid into the tower, the at least one cooling fluid inlet arranged in a tower wall of the tower of the wind turbine; and the at least one cooling fluid inlet comprising at least one opening (<NUM>) defined by a tower door (<NUM>) and an intake plenum (<NUM>) coupled to an inner face (<NUM>) of the tower door (<NUM>) and surrounding the at least one opening (<NUM>) defined by the tower door;
at least one platform (<NUM>) positioned within the tower at a predetermined height above a foundation (<NUM>) of the wind turbine, configured to create a space within the tower between the platform (<NUM>) and the foundation (<NUM>) to provide a location for the installation of a filtration assembly (<NUM>);
said filtration assembly (<NUM>) arranged within the tower, the filtration assembly comprising a plurality of flow guiding structures that define a plurality of flow paths for providing a plurality of flow direction changes and/or flow velocity changes to the cooling fluid; and,
at least one cooling fluid outlet for directing the filtered cooling fluid within the tower;
wherein the filtration assembly is positioned between the at least one platform and the foundation of the wind turbine;
and wherein the plurality of flow guiding structures define a plurality of <NUM>-degree turns for the cooling fluid configured to slow the cooling fluid and configured to allow one or more particles in the cooling fluid to settle out.