Patent Application
20150267644
Industries, such as airlines and airline manufacturers, are always looking for ways to lower costs that are associated with flying. For example, airline manufacturers attempt to find different ways of lowering maintenance costs, reducing emissions, reducing noise and reducing fuel consumption.
Fuel prices are generally very volatile and are one of the largest expenses of an airline. Reducing these fuel expenses can help an airline compete in today's competitive market. Airline manufacturers may attempt to improve fuel efficiency using a variety of different methods. For example, more fuel efficient engines may be designed, aerodynamics may be improved, the weight of parts may be reduced, and the like. For example, changing the design of the primary nozzle or the vents that are associated with an engine, such as a bypass turbofan turbine engine, may be changed in an attempt to increase the performance of the engine. Improving these, and other, characteristics, however, can be very challenging and costly.
It should be appreciated that this Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to be used to limit the scope of the claimed subject matter.
Apparatus, system and methods described herein are directed at providing an integrated primary nozzle. According to an aspect, an integrated primary nozzle is formed using a forward cowl and an integrated panel. The integrated panel is concentric to the forward cowl and extends beyond an aft end of the forward cowl. An annular vent is formed between the outer surface of the integrated panel and the inner surface of the forward cowl. The integrated panel is an integrally formed combination of a portion of a primary nozzle outer wall, an acoustic treatment, and an aft cowl.
According to another aspect, a system for an integrated primary nozzle includes a nacelle, a forward cowl, and an integrated panel. The integrated panel is coupled to the nacelle or the engine and is disposed partially within the forward cowl. The integrated panel extends longitudinally beyond an aft end of the forward cowl. The integrated panel is an integrally formed combination of the primary nozzle outer wall, an acoustic treatment, and the aft cowl. An annular vent is defined by a gap that is between the outer surface of the integrated panel and the inner surface of the forward cowl. According to yet another aspect, a method is configured to form an integrated primary nozzle. The method includes manufacturing an integrated panel as an integrally formed combination of an aft cowl, an acoustic treatment, and a portion of a primary nozzle outer wall. A size of the annular vent is determined. The integrated panel is positioned concentrically to the forward cowl such that the annular vent has the determined size.
The features, functions, and advantages that have been discussed can be achieved independently in various embodiments of the present disclosure or may be combined in yet other embodiments, further details of which can be seen with reference to the following description and drawings.
The following detailed description is directed to an integrated primary nozzle. Utilizing the concepts and technologies described herein, an integrated primary nozzle is directed to one or more of a more optimally positioned annular vent, a larger acoustically treated area, a lower weight, an increase in primary nozzle performance, a reduction in part count, and a reduction in assembly hours.
Traditional annular vent designs splice multiple pieces of structure together to form an annular vent for an engine, such as a high bypass turbofan turbine engine. For example, a splice joint may be used to attach a cantilevered structure (hereinafter referred to as a “fairing”) to the aft end of the aft cowl with a stiffening bullnose at the forward end of the aft cowl. This type of design results in a relatively thick overall structure since each part that is spliced together has a different thickness. For example, using a traditional annular vent design results in a gap between the forward cowl and the fairing of the aft cowl that is larger than desired.
The integrated primary nozzle reduces the number of parts and weight from a traditional annular vent design by eliminating the splice and the fairing that is included in the traditional annular vent design as described herein. With fewer parts in the integrated primary nozzle, there may be a reduction in production and manufacturing costs by reducing the material and the assembly time and effort used to manufacture the annular vent.
The annular vent may be positioned farther aft as compared to the traditional annular vent design and the forward cowl may be moved farther aft since the gap formed by the annular vent may be reduced in size when compared to the gap that results from the traditional method of splicing multiple pieces of structure together. For example, in one embodiment the gap is reduced from about 1.5 inches to about 0.5 inches. Positioning the annular vent farther aft may result in a more optimally positioned annular vent. A larger portion of the primary nozzle outer wall may also be covered with acoustic treatment as compared to a traditional annular vent design. For example, acoustic treatment may cover the primary nozzle wall from about the aft end to a location beneath the forward cowl.
In the following detailed description, references are made to the accompanying drawings that form a part hereof, and which are shown by way of illustration, specific embodiments, or examples. Referring now to the drawings, in which like numerals represent like elements through the several figures, a configurable tray table and method for employing the same according to the various embodiments will be described.
Propulsion system 100 may include an engine 116 (e.g., a bypass turbofan gas turbine engine) that is housed in nacelle 110. Nacelle 110 is secured to a wing (not shown) using some fastening system (e.g., a strut, pylon). Nacelle 110 includes inlet 112 that supplies air to engine 116.
Propulsion system 100 includes a fan 114 that located at a forward end of the engine 116 near inlet 112. Air that passes through fan 114 is divided into a flow that passes through engine 116, flow used for cooling, that is eventually exhausted through the annular vent 240, and a flow that passes through a fan duct. Engine 116 produces a primary exhaust flow, discharged through a primary exhaust 250. Some of the fan exhaust flow, used as cooling air, passes through an annular vent 240. The fan exhaust flow, the primary exhaust flow, and the annular vent exhaust flow form the thrust that is generated by the engine. A plug 140 may be included depending on the design.
In bypass turbofan engines, the primary exhaust flow and the fan exhaust flow may be optimized for specific engines and/or specific operating conditions. For example, the positioning and the size of the annular vent may be changed depending on the desired operating characteristics. According to an embodiment, the integrated primary nozzle described herein positions the annular vent 240 farther aft compared to traditional designs. As a result, a relatively smaller gap may also be used in forming the annular vent 240 between the forward cowl 120 and aft cowl 130 since the fairing in traditional designs is not included in the integrated primary nozzle.
The integrated primary nozzle described herein may also include more acoustic treatment as compared to traditional designs. For example, acoustic treatment may be disposed longitudinally along a substantial length of the aft cowl 130 and beneath a portion of the forward cowl 120.
The illustration of propulsion system 100 is not meant to imply physical or architectural limitations to the manner in which different embodiments may be implemented. Other components in addition to and/or in place of the ones illustrated may be used. Some components may also be unnecessary in some embodiments. The following figures provide more detail with regard to the integrated primary nozzle.
As illustrated, annular vent 240 includes a space or gap 232 that is formed between and defined by the inner surface 216 of forward cowl 120 and an outer surface 218 of integrated panel 242. Instead of having a fairing that is connected to the primary nozzle outer wall 230, aft cowl 130 is integrated with primary nozzle outer wall 230 and acoustic treatment 220 to form integrated panel 242. In the example that is shown in
In contrast to splicing multiple pieces of structure together that results in relatively large gaps between the forward cowl 120 and aft cowl 130 (See
As illustrated, aft cowl 130 is coupled to primary nozzle outer wall 230 and forms an integrated panel 242 that is substantially a same uniform thickness. Comparing
View 260 illustrates an end view looking directly into the nacelle 100 and showing annular vent 240, primary exhaust 250 and plug 140. As illustrated, the forward cowl 120 and integrated panel 242 are concentric to one another. Integrated panel 242 is positioned partially within forward cowl 120 to form annular vent 240 having a gap 232. According to other embodiments, a forward cowl may be disposed in a different manner to an integrated panel. For example, the integrated panel 242 may be formed to have a square opening, or some other shape opening (e.g. oval) and the forward cowl may be formed to have a larger square opening, or some other shape opening.
Acoustic treatment 220 is directed at reducing the noise of the engine. One source of noise from an aircraft is engine noise. Different acoustic treatments may be used according to embodiments of the invention. For example, acoustic treatment 220 may be an acoustic liner that includes a honeycomb core sandwiched between a perforated front sheet and a solid back sheet. The perforated front sheet is aligned with the primary flow so that the sound waves pass through the front sheet and into the honeycomb core of acoustic treatment 220 where the sound waves are dissipated. The number of holes, the pattern of the holes, as well as other characteristics of acoustic treatment 220 may be changed depending on the application. Further, other types of acoustic treatments may be used. The acoustic treatment 220 that is shown in integrated primary nozzle system 200 may extend from a location beneath forward cowl 120 to near an aft end (or all of the way to the end) of the primary nozzle outer wall 230. According to an embodiment, the acoustic treatment extends to within a few inches (e.g., 1 inches, 2 inches, 3 inches) of the aft end 214 of integrated panel 242.
Forward cowl 320 and aft cowl 330 form an annular vent 340. A fairing 310 is attached to the primary nozzle outer wall 330 and is not integrated with the acoustic treatment 320. As can be seen, there is a gap 322 between fairing 310 and acoustic treatment 320. Further, there is an empty air space 325 between aft cowl 330, fairing 310 and primary nozzle outer wall 330.
As illustrated, fairing 310 is spliced to primary nozzle outer wall 330. In the fairing design illustrated in
As illustrated, the gap 322 between the forward cowl 120 and fairing 310 is approximately 1.5 inches. Other traditional annular designs may have different gaps, but the gaps are larger compared to the gap 232 of an integrated primary nozzle as shown in
Acoustic treatment 320 is illustrated on primary nozzle outer wall 330. The acoustic treatment 320 in
Turning now to the description of
The integrated primary nozzle system 400 is substantially similar to the integrated primary nozzle system 200 as illustrated in
Turning now to
Routine 500 begins at operation 510, where an integrated panel is manufactured. According to an embodiment, the integrated panel is an integrally formed combination of an aft cowl, acoustic treatment, and a portion of a primary nozzle outer wall. The acoustic treatment may be disposed between a primary nozzle outer wall and an aft cowl.
At operation 512, the acoustic treatment is disposed on the primary nozzle outer wall. According to an embodiment, the acoustic treatment is a honeycomb structure that includes small holes drilled on the side of the primary flow coming from an engine. Other types of acoustic treatments may be used. As discussed above, the acoustic treatment may be disposed along a length of the primary nozzle outer wall to an aft end of the aft cowl, near the aft end of the aft cowl, or some other length. According to an embodiment, the acoustic treatment is applied to the primary nozzle wall from about the aft end of the primary nozzle outer wall to a location beneath the inner surface of the forward cowl.
At operation 514, the aft cowl is integrated with the acoustic treatment and the primary nozzle outer wall. For example, a structure, such as sheet metal, may be coupled to the top of the acoustic treatment. According to another embodiment, the acoustic treatment is manufactured to include a top sheet that is directly integrated onto the acoustic treatment. According to an embodiment, the aft cowl is integrated with the acoustic treatment and the primary nozzle outer wall such that there is not a gap at the forward end.
From operation 510, routine 500 continues to operation 520, where a size of the annular vent is determined. The size of the annular vent may be determined using a variety of criteria. For example, the size of the annular vent may be based on the desired operating characteristics. According to an embodiment, the size of the annular vent is based on a size of the gap between the forward cowl and the integrated panel. Due to the structure and manufacturing method disclosed herein, a smaller gap may be used in forming the annular vent 240, 440 positioned between the forward cowl 120 and the integrated panel 242, 442 since the fairing in traditional designs is not included in the integrated primary nozzle as described herein. According to an embodiment, the gap may be sized to approximately 0.5 inches. Other gap sizes may be used depending on the application. For example, some turbine engines may operate more efficiently having a gap size of 0.3 inches to 0.6 inches and the like.
From operation 520, routine 500 continues to operation 530. At operation 520, the annular vent is positioned. As discussed above, the integrated panel may be positioned relative to the forward cowl to adjust the performance characteristics of the annular vent. According to an embodiment, the annular vent is positioned farther aft (e.g., 4 inches, 5 inches, 6 inches) as compared to a traditional annular vent as illustrated in
The subject matter described above is provided by way of illustration only and should not be construed as limiting. Various modifications and changes may be made to the subject matter described herein without following the example embodiments and applications illustrated and described, and without departing from the true spirit and scope of the present disclosure, which is set forth in the following claims.
