A mixed exhaust device with adjustable outer area

Abstract

The application discloses a mixed exhaust device with adjustable outer area, and belongs to the technical field of aero-engines. The device comprises an inner cone cavity, a mixer, a casing, an open hole blanking ring, a support ring and a multi-gear self-locking nut. The open hole blanking ring can be translated along the radial direction and is fixed at different radial positions by selecting self-locking nuts of different gears, so that the outer area of the mixed exhaust device is changed, and then the pressure difference between the outer area and the inner area of the load-bearing outlet of the core engine is adjusted. As a result, the same device can adapt to the test requirements of various core engines and different working conditions, and the production cost is greatly reduced. Meanwhile, air holes are uniformly arranged on the open hole blanking ring, so that the gas flow resistance can be effectively reduced. The application replaces a complex automatic continuous adjusting mechanism with a simple manual multi-gear radial translation structure, and has the advantages of simple structure, intuitive operation, low cost and high reliability.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and in particular to a hybrid exhaust device with adjustable bypass area. Background Technology

[0002] In turbofan engine core testing, a mixing exhaust device is typically required at the rear load outlet to adjust the pressure difference between the outer and inner cores, thereby supporting the core engine to achieve the required test conditions. Furthermore, a core engine often needs to be tested under multiple different operating conditions, and the test conditions for different core engines vary significantly. These changes in operating conditions directly lead to alterations in the pressure difference between the outer and inner cores at the rear load outlet.

[0003] However, traditional mixed exhaust systems have a fixed structure, and their outer bypass area cannot be adjusted. They can only match a specific pressure difference under a single operating condition and cannot adapt to different pressure differences within the outer bypass. When different operating conditions or different core engines need to be tested, the entire mixed exhaust system must be replaced, resulting in high testing costs and long testing cycles. In addition, the gas flow loss of traditional mixed exhaust systems is relatively large, further affecting the accuracy and efficiency of the tests.

[0004] Therefore, there is an urgent need for a hybrid exhaust device that can flexibly adjust the outer duct area, adapt to the needs of multi-condition testing, and has low flow loss. Summary of the Invention

[0005] The present invention aims to solve the technical problem that the existing hybrid exhaust device has a fixed outer duct area and cannot adapt to various core machine test conditions. It provides a hybrid exhaust device with an adjustable outer duct area, which can flexibly adjust the outer duct area to meet the needs of multi-condition test, while reducing flow loss.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] An adjustable bypass area hybrid exhaust device is installed at the rear of the load-bearing outlet of the aero-engine core. The hybrid exhaust device includes an inner bypass channel and an outer bypass channel, and further includes: Support ring, fixed to the casing; An opening-type plug ring is radially movable between the support ring and the mixer, and at least two self-locking nuts at different radial positions are fixed on the opening-type plug ring. A guide structure is disposed between the opening plug ring and the support ring to guide the opening plug ring to translate radially. Fasteners, passing through the support ring and selectively connected to the self-locking nut on the opening plug ring, fix the opening plug ring in different radial positions, thereby changing the area of ​​the outer duct channel.

[0008] Furthermore, the opening plug ring is fixed with a first-stage self-locking nut, a second-stage self-locking nut, and a third-stage self-locking nut arranged radially at intervals. The fastener can cooperate with one of the self-locking nuts respectively to realize the three-stage adjustment of the outer duct area, so as to adapt to the outer duct pressure difference requirements under three typical working conditions.

[0009] Furthermore, the guide structure includes a groove fixed to the opening plug ring and a sliding self-locking nut slidably disposed in the groove. The sliding self-locking nut is connected to the fastener and can slide freely in the groove to ensure the stability and accuracy of the opening plug ring during translation.

[0010] Furthermore, the perforated plug ring has evenly distributed vent holes for gas flow to reduce flow resistance. This design significantly reduces the flow resistance of gas passing through the perforated plug ring, reduces pressure loss, and improves test efficiency.

[0011] Furthermore, multiple perforated plugs are evenly distributed circumferentially, and each perforated plug is located at the same radial position, achieving uniform circumferential adjustment and ensuring the symmetry of airflow mixing.

[0012] Furthermore, the number of the perforated plug rings is at least three.

[0013] Furthermore, each opening plug ring is provided with four first-position self-locking nuts, four second-position self-locking nuts, four third-position self-locking nuts, as well as two sliding grooves and two sliding self-locking nuts, and the self-locking nuts and sliding grooves of the same position are located in the same radial position.

[0014] Furthermore, each type of self-locking nut and sliding self-locking nut is symmetrically arranged along the central axis of the opening plug ring.

[0015] Furthermore, the support ring is fixed to the casing by welding, and bolt holes for fasteners to pass through are provided on the support ring at the position corresponding to the opening and plugging ring.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: 1. Adjustable outer duct area and strong adaptability to multiple working conditions: This invention can precisely change the outer duct area by fixing the opening plug ring to the self-locking nut at different positions, thereby adjusting the pressure difference between the inner and outer ducts at the rear bearing outlet. This allows the same set of mixed exhaust devices to be adapted to multiple core machines and multiple test conditions, greatly reducing the cost of test equipment.

[0017] 2. Simple structure and intuitive operation: This invention adopts a combination of manual radial translation and multi-position self-locking nut fixing, which eliminates the need for complex actuators, connecting rods or control systems. Operators only need to tighten the bolts to complete the gear switching. The structure has high reliability and is easy to maintain.

[0018] 3. Low flow loss: The evenly spaced vent holes on the perforated plug ring effectively reduce gas flow resistance and significantly reduce pressure loss, which helps improve the accuracy of test data.

[0019] 4. Significantly reduced production costs: One set of hybrid exhaust device of the present invention can replace multiple sets of traditional fixed area devices, which not only reduces hardware investment, but also shortens the test preparation cycle, resulting in good economic benefits. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a perspective view of a hybrid exhaust device with adjustable outer duct area according to an embodiment of the present invention; Figure 2 This is a front view of the hybrid exhaust device with adjustable outer duct area according to an embodiment of the present invention; Figure 3 for Figure 2 A magnified view of the area within the dashed line; Figure 4 This is a rear view of the hybrid exhaust device with adjustable outer duct area according to an embodiment of the present invention; Figure 5 for Figure 4 A magnified view of the area within the dashed line.

[0022] In the diagram: 1-Cryogenic gas; 2-High-temperature gas; 3-Inner conical cavity; 4-Mixer; 5-Casing; 6-Opening plug ring; 7-Support ring; 8-Bolt; 9-Section I self-locking nut; 10-Section II self-locking nut; 11-Section III self-locking nut; 12-Sliding self-locking nut; 13-Slide groove; 14-Rivet. Detailed Implementation

[0023] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] like Figures 1 to 5 As shown in the figure, an embodiment of the present invention provides a mixed exhaust device with adjustable outer bypass area, which is installed at the rear of the load-bearing outlet of the aero-engine core and is used to adjust the pressure difference between the outer and inner bypass during the test.

[0026] The mixing exhaust device mainly includes: an inner conical cavity 3, a mixer 4, a casing 5, an opening plug ring 6, a support ring 7, a bolt 8, a first-position self-locking nut 9, a second-position self-locking nut 10, a third-position self-locking nut 11, a sliding self-locking nut 12, a slide groove 13, and a rivet 14.

[0027] The mixer 4 is a rotating structure fixed to the front-end engine. The area between the mixer 4 and the inner cone cavity 3 forms the inner passage, through which high-temperature exhaust gas 2 from the turbine flows. The area between the mixer 4 and the casing 5 forms the outer bypass passage, through which low-temperature gas 1 from the fan flows.

[0028] The support ring 7 is fixed to the casing 5 by welding, and bolt holes are provided at the positions corresponding to the opening plug ring 6 (see...). Figure 4 , Figure 5 The perforated plug ring 6 is radially movable between the support ring 7 and the mixer 4. At least three perforated plug rings 6 are provided for ease of installation and maintenance. In this embodiment, a total of six perforated plug rings 6 are provided, circumferentially distributed on the outside of the mixer 4, and all perforated plug rings 6 are in the same radial position (see [reference]). Figure 2 ).

[0029] like Figure 3As shown, each perforated plug ring 6 is secured with four I-position self-locking nuts 9, four II-position self-locking nuts 10, and four III-position self-locking nuts 11 by rivets 14. These self-locking nuts are radially spaced, forming three different fixed positions. The fastener (bolt 8) can engage with one of the self-locking nuts to achieve three-position adjustment of the outer diameter area. Simultaneously, each perforated plug ring 6 is also welded with two sliding grooves 13, each groove 13 containing a sliding self-locking nut 12 that can slide freely within it. The sliding self-locking nut 12 is connected to the fastener. Self-locking nuts and sliding grooves 13 of the same position are maintained in the same radial position to ensure the synchronicity and accuracy of the adjustment.

[0030] Furthermore, to ensure uniform force and smooth movement of the perforated plug ring 6 during radial translation, and to prevent skewing or jamming, the self-locking nuts (i.e., self-locking nuts 9 (I-position), 10 (II-position), and 11 (III-position)) and the sliding self-locking nuts 12 are symmetrically arranged along the central axis of the perforated plug ring 6. Specifically, for each perforated plug ring 6, the four I-position self-locking nuts 9 are divided into two groups, with the two nuts in each group arranged symmetrically about the central axis of the perforated plug ring 6; similarly, the four II-position self-locking nuts 10 and the four III-position self-locking nuts 11 are also symmetrically distributed about their central axes. The two sliding grooves 13 and the two sliding self-locking nuts 12 located within them are also symmetrical about the central axis of the perforated plug ring 6. The axisymmetric layout allows the fastening force applied by the fastener (bolt 8) to each gear self-locking nut or sliding self-locking nut 12 to be evenly transmitted to the entire opening plug ring 6. During radial translation, the sliding self-locking nuts 12 on both sides slide synchronously in the slide groove 13, effectively preventing the opening plug ring 6 from tilting or jamming due to unilateral force, thereby ensuring the smoothness of gear switching and the positional accuracy after fixing, and improving the working reliability of the device under airflow impact.

[0031] In the initial state, bolt 8 passes through the bolt hole on the support ring 7 and is tightened onto the self-locking nut of a certain position (e.g., self-locking nut 9 of position I), so that the opening plug ring 6 is in the corresponding radial position. When it is necessary to change the outer diameter area, the operator first loosens bolt 8 to disengage it from the self-locking nut, and then pushes the opening plug ring 6 radially inward or outward. At this time, the sliding self-locking nut 12 slides relative to it in the groove 13, guiding the opening plug ring 6 to move radially in a straight line. When the opening plug ring 6 moves to the target position (e.g., position II or position III), bolt 8 is aligned with the self-locking nut of that position (e.g., four bolts 8 are screwed into four self-locking nuts 10 of position II) and tightened to fix it. In this way, the opening plug ring 6 is locked in the new radial position. Preferably, the bolt 8 on the sliding self-locking nut 12 is also kept tightened in the fixed state to further improve the stability of the opening plug ring 6; it needs to be loosened before adjustment.

[0032] The radial position of the perforated plug ring 6 directly determines the flow area of ​​the outer duct channel: when the perforated plug ring 6 moves inward (closer to the mixer 4), the area of ​​the outer duct channel decreases; conversely, when it moves outward, the area increases. By selecting different self-locking nut positions, three different outer duct area setting values ​​can be obtained, thereby correspondingly adjusting the pressure difference between the inner and outer ducts at the rear bearing outlet of the core machine to meet the needs of different test conditions.

[0033] Specifically, each perforated sealing ring 6 has multiple vent holes evenly distributed on it (see...). Figure 2 , Figure 3 These vents are used for gas flow to reduce flow resistance. When cryogenic gas 1 flows through the perforated plug ring 6, these vents provide a smooth airflow path, significantly reducing flow resistance and pressure loss.

[0034] This invention achieves adjustable outer bypass area by manually radially shifting the perforated plug ring 6 and fixing it with a three-position self-locking nut. One device can replace multiple traditional fixed-area mixers, significantly reducing equipment costs and preparation time for core engine testing. Simultaneously, the vent design on the perforated plug ring reduces flow losses, improving test accuracy. This device is simple in structure, easy to operate, and highly reliable, making it particularly suitable for rapid adaptation to various operating conditions on aero-engine core engine test benches.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A mixed exhaust device with adjustable outer bypass area, installed at the rear of the aft load-bearing outlet of an aero-engine core, the mixed exhaust device comprising an inner bypass channel and an outer bypass channel, characterized in that, Also includes: Support ring (7) is fixed to the casing (5); An opening plug ring (6) is radially movable between the support ring (7) and the mixer (4), and at least two self-locking nuts with different radial positions are fixed on the opening plug ring (6); A guide structure is disposed between the opening plug ring (6) and the support ring (7) to guide the opening plug ring (6) to translate radially; Fasteners, passing through the support ring (7) and selectively connected to the self-locking nut on the opening plug ring (6), fix the opening plug ring (6) in different radial positions, thereby changing the area of ​​the outer duct channel.

2. The adjustable duct area mixed exhaust device according to claim 1, characterized in that: The opening plug ring (6) is fixed with a first-stage self-locking nut (9), a second-stage self-locking nut (10) and a third-stage self-locking nut (11) arranged radially at intervals. The fastener can cooperate with one of the self-locking nuts to realize the three-stage outer duct area adjustment.

3. The adjustable duct area hybrid exhaust device according to claim 1 or 2, characterized in that: The guide structure includes a groove (13) fixed on the opening plug ring (6) and a sliding self-locking nut (12) slidably disposed in the groove (13). The sliding self-locking nut (12) is connected to the fastener and can slide freely in the groove (13).

4. The adjustable duct area mixed exhaust device according to claim 3, characterized in that: The perforated plug ring (6) has evenly distributed vent holes for gas flow to reduce flow resistance.

5. The adjustable duct area mixed exhaust device according to claim 4, characterized in that: The perforated plug rings (6) are evenly distributed in a circumferential direction, and each perforated plug ring (6) is located in the same radial position.

6. The adjustable duct area mixed exhaust device according to claim 5, characterized in that: The number of the perforation plugs (6) is at least 3.

7. The adjustable duct area mixed exhaust device according to claim 5, characterized in that: Each opening plug ring (6) is provided with four first-position self-locking nuts (9), four second-position self-locking nuts (10), four third-position self-locking nuts (11), two grooves (13) and two sliding self-locking nuts (12), and the self-locking nuts and grooves (13) of the same position are located in the same radial position.

8. The adjustable duct area mixed exhaust device according to claim 7, characterized in that: Each type of self-locking nut and sliding self-locking nut (12) is symmetrically arranged along the central axis of the opening plug ring (6).

9. The adjustable duct area mixed exhaust device according to claim 1, characterized in that: The support ring (7) is fixed to the casing (5) by welding. The support ring (7) has bolt holes for fasteners to pass through at the position corresponding to the opening plug ring (6).

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