An S-bend nozzle including a web-type load-bearing structure and its application

Abstract

The present invention relates to an S-bend nozzle including a web-type load-bearing structure and its application, belonging to the field of aero-engines. The S-bend nozzle is axially divided into a nozzle convergence section, a transition section, and a nozzle outlet, and its outer wall is coupled with a web-type load-bearing structure. The web-type load-bearing structure includes a first longitudinal web located on a symmetrical cross-section of the S-bend nozzle and second longitudinal webs located on both sides of the symmetrical cross-section. The first longitudinal web extends axially from the nozzle outlet end to the nozzle inlet end, and the second longitudinal web extends axially from the nozzle outlet end to the normal cross-section of the transition section wall. Local transverse webs are provided on both the nozzle outlet end cross-section and the transition section wall normal cross-section. The present invention effectively suppresses deformation of the S-bend nozzle structure by arranging longitudinal webs and local transverse webs at appropriate positions of the nozzle structure, thereby further achieving lightweight design requirements while meeting strength requirements.

Description

Technical Field

[0001] The present invention belongs to the field of aviation engines, and in particular relates to an S-bend nozzle comprising a web-type load-bearing structure and its application. Background Art

[0002] The S-bend nozzle is one of the key components for achieving stealth aircraft, and has many characteristics, including large size, thin thickness, and complex surface curvature. The complex aerodynamic pressure and aerodynamic thermal loads inside the S-bend nozzle will cause complex structural deformation, which may lead to a decrease in the nozzle's aerodynamic performance or even damage the nozzle structure. Therefore, it is necessary to consider the use of reasonable structures and methods to suppress the structural deformation of the S-bend nozzle. In order to ensure the aerodynamic performance and structural integrity of stealth aircraft, reasonable methods must be adopted to suppress the structural deformation of the S-bend nozzle, including the use of load-bearing structural supports, material improvements, surface coatings, etc., to reduce the impact of internal pressure and thermal loads on the S-bend nozzle structure, ensure that the S-bend nozzle can operate stably, maintain its designed stealth characteristics, and extend its service life.

[0003] The web-type load-bearing structure is a commonly used structural reinforcement method in engineering, which can effectively improve the load-bearing capacity and deformation resistance of the target structure. Due to the complex structural deformation mode of the S-bend nozzle, the design of the web-type load-bearing structure needs to be combined with the specific deformation characteristics of the nozzle, including considering the influence of factors such as the aerodynamic pressure distribution inside the nozzle and the strength and stiffness of the nozzle material. When designing the web-type load-bearing structure, in order to avoid problems such as excessive overall structural mass or poor deformation suppression effect, the web-type load-bearing structure needs to be designed according to the specific deformation characteristics of the S-bend nozzle to ensure the balance between its deformation suppression effect and overall structural quality, improve the performance of the S-bend nozzle while extending its service life.

[0004] The current design method of web-type load-bearing structures in engineering is relatively simple, and there is a lack of optimization work on the layout dimensions of each web structure. In the design of S-bend nozzles, engineering technicians currently still use the method of changing the overall wall thickness of the nozzle to suppress deformation. However, there is little research and application of web-type load-bearing structures in suppressing S-bend nozzle deformation, and the optimization work in layout dimension design is not mature. Therefore, in the design process of S-bend nozzles, it is necessary to optimize the layout dimensions of the web-type load-bearing structure to improve its effect in suppressing deformation and reduce the weight of the structure, so as to give full play to the structural advantages and meet the requirements of lightweight design. By adopting an optimized web-type load-bearing structure, the deformation resistance and load-bearing capacity of the engine tail nozzle can be effectively improved, making the entire nozzle structure safer and more reliable. Summary of the Invention

[0005] Technical issues to be solved:

[0006] In order to avoid the shortcomings of the existing technology, the present invention provides an S-bend nozzle and its application including a web-type load-bearing structure, which effectively suppresses the deformation of the S-bend nozzle structure by arranging longitudinal webs and local transverse webs at appropriate positions of the nozzle structure, thereby further realizing lightweight design requirements while meeting strength requirements.

[0007] The technical solution of the present invention is: an S-bend nozzle including a web-type load-bearing structure, wherein the S-bend nozzle is divided into a nozzle convergence section, a transition section, and a nozzle outlet and other straight sections along the axial direction, and the outer wall surface of the S-bend nozzle is coupled with the web-type load-bearing structure;

[0008] The web-type load-bearing structure includes a first longitudinal web located on the symmetrical section of the S-bend nozzle, and a second longitudinal web located on both sides of the symmetrical section. The first longitudinal web extends axially from the nozzle outlet end to the nozzle inlet end, and the second longitudinal web extends axially from the nozzle outlet end to the normal section of the transition section wall. Local transverse webs are provided on both the nozzle outlet end section and the transition section wall normal section.

[0009] A further technical solution of the present invention is: the first longitudinal web includes a longitudinal web with a symmetrical cross-section on the upper wall surface and a longitudinal web with a symmetrical cross-section on the lower wall surface located on the upper and lower wall surfaces, with thicknesses of D3 and D4 respectively; the distance between the upper edge of the longitudinal web with a symmetrical cross-section on the upper wall surface and the highest point of the upper wall surface of the nozzle is a height H3, and the distance between the lower edge of the longitudinal web with a symmetrical cross-section on the lower wall surface and the lowest point of the lower wall surface of the nozzle is a height H4, and the heights H3 and H4 account for 4% to 15% of the total length of the nozzle.

[0010] A further technical solution of the present invention is: the second longitudinal web includes two side longitudinal webs arranged on the upper wall of the nozzle, and two side longitudinal webs arranged on the lower wall; the two side longitudinal webs of the upper and lower walls are symmetrical and parallel to the symmetrical section of the S-bend nozzle.

[0011] A further technical solution of the present invention is that the longitudinal webs on both sides of the nozzle upper wall start from the nozzle outlet and extend forward to the normal section of the transition section wall. The distance between their upper edges and the highest point of the nozzle upper wall is H3, the axial length X accounts for 50%-55% of the total length of the nozzle, the thicknesses are D5 and D6 respectively, and the distance W1 between them and the symmetrical section of the S-bend nozzle accounts for 15%-20% of the width of the nozzle outlet.

[0012] A further technical solution of the present invention is: the longitudinal webs on both sides of the lower wall of the nozzle start from the nozzle outlet end and extend forward to the nozzle inlet end; the distance between their lower edges and the lowest point of the lower wall of the nozzle is H4, the thicknesses are D7 and D8 respectively, and the distance W2 between them and the symmetrical cross-section of the S-bend nozzle accounts for 15% to 20% of the width of the nozzle outlet end.

[0013] A further technical solution of the present invention is: the local transverse web on the cross-section of the nozzle outlet end is perpendicularly connected to the longitudinal webs on both sides of the upper and lower wall surfaces, its height is consistent with the height of the longitudinal webs on both sides of the upper and lower wall surfaces, its width L accounts for 40% to 50% of the width of the nozzle outlet end, and its thickness is D9.

[0014] A further technical solution of the present invention is that the distance between the local transverse web structure on the normal section of the transition section wall and the nozzle outlet end section is equal to the axial length X of the longitudinal webs on both sides of the nozzle upper wall surface, and is perpendicular to the longitudinal webs on both sides of the upper and lower walls. Its width and height are consistent with the local transverse webs located at the nozzle outlet end section, and its thickness is D 10 .

[0015] A further technical solution of the present invention is that the local transverse web includes a left transverse web and a right transverse web, and adjacent edges of the left and right transverse webs are respectively connected to edges of the second longitudinal web.

[0016] A further technical solution of the present invention is that the thickness of each web in the web-type load-bearing structure is 0.5 to 1.5 mm.

[0017] An S-bend nozzle including a web-type load-bearing structure is used on a stealth aircraft. The upper and lower edges of the longitudinal web and partial transverse web are respectively connected to the outer skin of the aircraft to limit the deformation of the nozzle structure in various directions.

[0018] Beneficial effects

[0019] The beneficial effect of the present invention is that the technical solution of the present invention adopts the method of arranging the web structure at an appropriate position on the S-bend nozzle structure to effectively suppress the deformation of the nozzle. Improper selection of the web layout position will usually lead to local over-constraint or under-constraint of the nozzle structure, thereby causing local large deformation on the nozzle wall, which is not conducive to meeting the deformation requirements of the nozzle structure. Considering the complex deformation mode of the S-bend nozzle itself, the uniformly distributed web layout method will lead to a large amount of web material redundancy and poor deformation suppression ability. It is necessary to adjust the web layout position according to its specific deformation characteristics. By analyzing the deformation mode of the S-bend nozzle, it is found that the nozzle deformation is mainly divided into the global upward deformation at the lip of the nozzle outlet section and the local expansion at the rear of the nozzle convergence section. According to the characteristics of the S-bend nozzle deformation mode, this solution arranges the web on the nozzle structure in a targeted manner and optimizes the corresponding layout size. Specifically, by determining the position, shape and size of the web, the overall and local stiffness is improved, thereby suppressing deformation, which has obvious deformation suppression advantages and structural weight advantages. The technical difficulty of this invention lies in the need for targeted optimization of the web structure layout and dimensions based on the specific deformation characteristics of the S-bend nozzle. The application of the technical solution of this invention can effectively suppress the deformation of the S-bend nozzle, improving its load-bearing capacity and deformation resistance. This solution also has the advantage of lightweight structure, reducing overall structural mass and improving the maneuverability of the aircraft.

[0020] After experimental verification, when the web thickness is 0.5mm, the height H3, H4 and the local transverse web width are 50mm, and fixed supports are used at the upper and lower edges of the web to constrain the structural deformation, the finite element method is used to calculate the deformation distribution of the S-bend nozzle without a web structure, the S-bend nozzle with a web structure, and the traditional S-bend nozzle with a web structure. The deformation distribution cloud diagrams of the three different structures are shown as follows: Figure 5-Figure 7 As shown in (unit: mm). The analysis and calculation results show that, relying on the web structure's suppressive effect on nozzle deformation, the maximum deformation of the nozzle can be reduced to 4.38% of the original maximum deformation, meeting the engineering deformation requirements and proving the effectiveness of the web-type load-bearing structure designed in this invention.

[0021] When a traditional web-type structure is used to suppress S-bend nozzle deformation, with the web thickness at all locations being 2mm and fixed supports at the upper and lower edges of the web to constrain structural deformation, the maximum deformation of the nozzle structure is 1.35mm. The overall structural weight of the web-type S-bend nozzle is 26.81kg, and the web weight is 16.88kg. It can be seen that the maximum deformation of the web-type load-bearing structure S-bend nozzle in the technical solution of the present invention, which has been optimized in layout and size, is 36.67% of that of the traditional web-type S-bend nozzle, and the web structure weight is 15.88% of that of the traditional web-type structure. In other words, the technical solution of the present invention not only reduces the structural deformation of the S-bend nozzle, but also has a significant advantage in structural weight compared to the traditional web-type structure.

[0022] Comparison between the technical solution of the present invention and the traditional web-type structure

[0023] BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic structural diagram of an S-bend nozzle including a web-type load-bearing structure, which may be selected according to an embodiment of the present invention;

[0025] Figure 2 is a top view of an S-bend nozzle including a web-type load-bearing structure, which can be selected according to an embodiment of the present invention;

[0026] Figure 3 3. This is a bottom view of an S-bend nozzle including a web-type load-bearing structure, which may be selected according to an embodiment of the present invention;

[0027] Figure 4 is a front view of an S-bend nozzle including a web-type load-bearing structure, which can be selected according to an embodiment of the present invention;

[0028] Figure 5 This is the deformation distribution cloud diagram of the S-bend nozzle without the web-type load-bearing structure;

[0029] Figure 6 The deformation distribution cloud diagram of the S-bend nozzle including the web-type load-bearing structure of the present invention;

[0030] Figure 7 This is the deformation distribution cloud diagram of the traditional web-type S-bend nozzle;

[0031] Figure 8 This is a deformation distribution cloud diagram of an embodiment of the present invention;

[0032] Figure 9 This is the stress distribution cloud diagram of this embodiment.

[0033] Explanation of the accompanying symbols: 1. Nozzle convergence section; 2. Nozzle outlet and other straight sections; 3. Longitudinal web of the symmetrical section of the upper wall; 4. Longitudinal web of the symmetrical section of the lower wall; 5-6. Longitudinal webs on both sides of the symmetrical section of the upper wall; 7-8. Longitudinal webs on both sides of the symmetrical section of the lower wall; 9. Local transverse web of the normal section of the transition section wall; 10. Local transverse web of the outlet end section. DETAILED DESCRIPTION

[0034] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0036] To address the limited effectiveness of existing S-bend nozzle deformation suppression structures, the present invention proposes an S-bend nozzle with a web-type load-bearing structure, comprising a nozzle convergent section, an outlet straight section, a longitudinal web, and a partial transverse web. The front end of the nozzle convergent section forms the inlet of the S-bend nozzle, connected to the turbine engine outlet, while the end of the nozzle outlet straight section forms the outlet of the S-bend nozzle.

[0037] By analyzing the deformation modes of an S-bend nozzle, it was found that nozzle deformation is primarily due to global upward deformation at the nozzle exit lip and local expansion at the rear of the nozzle convergent section. Therefore, longitudinal webs are placed along the symmetrical section of the S-bend nozzle, on both sides of the nozzle, extending forward from the nozzle exit to the nozzle inlet, and along the normal section of the transition section. Local transverse webs are also placed along the nozzle exit and along the normal section of the transition section to resist circumferential loads. Optimizing the layout further exploits the potential of the web structure, improving its deformation suppression capability while also achieving weight reduction. The longitudinal web structure on the upper and lower nozzle walls consists of three parts: the upper and lower longitudinal webs on the symmetrical section extend from the nozzle exit to the nozzle inlet; the longitudinal webs on both sides of the symmetrical section on the upper wall extend forward from the nozzle exit to the normal section of the transition section; and the longitudinal webs on both sides of the symmetrical section on the lower wall extend forward from the nozzle exit to the nozzle inlet. The webs are symmetrical about the symmetrical section of the nozzle.

[0038] Preferably, the thickness of the longitudinal web, i.e. D3, D4, D5, D6, D7, D8, is recommended to be in the range of 0.5 to 1.5 mm to avoid excessive structural weight due to excessive thickness or processing difficulties and buckling inside the web due to too small thickness.

[0039] Preferably, the distance between the upper edge of the longitudinal web on the nozzle's upper wall and the highest point on the nozzle's upper wall is H3, and the distance between the lower edge of the longitudinal web on the nozzle's lower wall and the lowest point on the nozzle's lower wall is H4. H3 and H4 represent 4% to 15% of the nozzle's total length, respectively. This prevents excessive structural weight due to excessive height or excessive local constraints due to low height, leading to stress concentration at the joints. This also leaves sufficient design space for the aircraft's outer skin layout. The distances W1 and W2 between the longitudinal webs on either side of the nozzle's symmetrical cross-section can be optimized based on the S-bend nozzle's deformation suppression requirements, representing 15% to 20% of the nozzle's exit width. This avoids offsetting the high deformation region due to excessive or insufficient distance, resulting in ineffective deformation suppression. The axial length X of the webs on either side of the nozzle's upper wall represents 50% to 55% of the nozzle's total length.

[0040] In this technical solution, the longitudinal webs extend forward from the nozzle outlet to the nozzle inlet, completely covering the nozzle's high-deformation areas, such as the straight section at the nozzle outlet and the rear half of the nozzle's convergent section. This effectively improves the nozzle's overall structural rigidity and significantly reduces the global upward warping deformation at the nozzle lip, achieving better overall deformation suppression. The longitudinal webs on either side of the symmetrical section of the upper wall, combined with the symmetrical longitudinal plates, enhance deformation suppression capabilities in the high-deformation areas of the nozzle's upper wall at the outlet.

[0041] Preferably, the width L of the local transverse web located on the cross-section of the nozzle outlet end accounts for 40% to 50% of the width of the nozzle outlet section. It is closely attached to the nozzle outlet end and vertically connected to the longitudinal webs on both sides of the upper and lower walls. It remains perpendicular to the nozzle axis, and its height is consistent with the height of the longitudinal webs connected to it.

[0042] Preferably, the width and height of the local transverse web on the normal section of the nozzle transition section wall are consistent with the width and height of the local transverse web on the nozzle outlet end section, are perpendicular to the longitudinal webs on both sides of the upper and lower walls, and are parallel to the local transverse web on the nozzle outlet end section. The axial distance of the local transverse web on the normal section of the transition section wall relative to the outlet end is consistent with the axial length of the webs on both sides of the symmetrical section of the nozzle upper wall, accounting for 50%-55% of the total length of the nozzle. The thickness parameters of each local transverse web, i.e., D9, D 10 , about 0.5 to 1.5 mm.

[0043] In this technical solution, localized transverse webs arranged along the normal cross-section of the transition section wall effectively suppress expansion deformation caused by circumferential loads. The thickness of each web, depending on the web configuration, has a limited effect on nozzle deformation. The web layout adopted in this technical solution, with web thicknesses close to the lower limit, does not significantly affect the S-bend nozzle's structural deformation suppression, maintaining effective support and reinforcement for all nozzle components, significantly reducing structural weight.

[0044] In a preferred embodiment of the present invention, structural deformation of the S-bend nozzle can be further suppressed by applying fixed constraints at the upper and lower edges of the web. This constraint further reduces deformation while preventing the nozzle's structural stress from exceeding the material's yield limit. In practical engineering contexts, considering that aircraft skins are often made of non-heat-resistant materials such as aluminum alloy, it is recommended that riveting be used to achieve fixed support constraints.

[0045] The application of an S-bend nozzle including a web-type load-bearing structure of the present invention to a stealth aircraft can effectively suppress the deformation of the S-bend nozzle, improve its load-bearing capacity and anti-deformation ability, and at the same time, this solution has the advantage of lightweight structure, can reduce the overall structural mass, and improve the maneuverability of the aircraft.

[0046] The above technical solution is further analyzed and explained below with reference to the accompanying drawings.

[0047] Example:

[0048] Reference Figure 1-Figure 4 As shown, this embodiment shows an S-bend nozzle with a web-type load-bearing structure, comprising a nozzle convergent section 1, a straight section 2 equal to the nozzle outlet, a longitudinal web 3 of a symmetrical section on the upper wall surface, a longitudinal web 4 of a symmetrical section on the lower wall surface, longitudinal webs 5-6 on either side of the symmetrical section on the upper wall surface, longitudinal webs 7-8 on either side of the symmetrical section on the lower wall surface, a local transverse web 9 of the normal section of the transition section wall surface, and a local transverse web 10 of the outlet end section. These longitudinal webs and local transverse webs together constitute the web-type load-bearing structure of the S-bend nozzle, which suppresses nozzle deformation during operation by increasing the overall and local stiffness of the S-bend nozzle structure.

[0049] Furthermore, in this embodiment, the nozzle has a thickness of 1.6 mm, a total length of 1054 mm, a width of the outlet straight pipe section of 541.42 mm, a thickness of each web of 0.5 mm, a height H3 and H4 of 50 mm, and a width of the local transverse web of 50 mm.

[0050] Specifically, in this embodiment, the longitudinal webs of the symmetrical sections of the upper and lower walls of the S-bend nozzle including the web-type load-bearing structure extend forward from the nozzle outlet end to the nozzle inlet end in the symmetrical section of the nozzle. The height H3 of the longitudinal webs on the upper and lower walls of the nozzle is 4% to 15% of the total length of the nozzle. In this embodiment, it is 4.74%, that is, 50 mm. The thickness of the longitudinal webs is 0.5-1.5 mm to avoid excessive weight of the structure due to excessive thickness or processing difficulties and buckling inside the web due to too small thickness. In this embodiment, it is 0.5 mm.

[0051] Specifically, in this embodiment, the longitudinal webs on either side of the symmetrical section of the upper wall of the S-bend nozzle, which includes a web-type load-bearing structure, extend from the nozzle outlet to the normal section of the transition section wall. The distance between the longitudinal webs on either side of the symmetrical section of the nozzle and the symmetrical section is 15% to 20% of the nozzle outlet width to avoid offsetting the large deformation area due to excessive or insufficient distance, which would result in ineffective deformation suppression. In this embodiment, the distance is 19.4%, or 105 mm. The axial length of the webs on either side of the nozzle upper wall is 50% to 55% of the total nozzle length, or 52.2%, or 550 mm, in this embodiment. The height H3 of the longitudinal webs on the upper wall of the nozzle is consistent with that of the longitudinal webs on the symmetrical section, or 50 mm. The thickness of the longitudinal webs is 0.5 to 1.5 mm, or 0.5 mm in this embodiment.

[0052] Specifically, in this embodiment, the longitudinal webs on either side of the symmetrical section of the lower wall of the S-bend nozzle, which includes a web-type load-bearing structure, extend from the nozzle outlet to the nozzle inlet. The distance between the longitudinal webs on either side of the symmetrical section and the symmetrical section is 15% to 20% of the nozzle outlet width, or 19.4% in this embodiment, or 105 mm. The height H4 of the longitudinal webs on the lower wall of the nozzle is the same as that of the longitudinal webs on the symmetrical section, or 50 mm. The thickness of the longitudinal webs is 0.5-1.5 mm, or 0.5 mm in this embodiment.

[0053] Specifically, in this embodiment, the local transverse web at the outlet end of the S-bend nozzle, which includes a web-type load-bearing structure, is tightly attached to the cross-section of the nozzle outlet end face, and is vertically connected to the longitudinal webs on both sides of the symmetrical cross-section of the upper and lower walls. Its height is consistent with the height of the longitudinal webs connected to it, that is, 50 mm; the width is 40% to 50% of the width of the nozzle outlet section, and in this embodiment, it is 41.1%, that is, 222 mm; the thickness of the local transverse web at the outlet end of the nozzle is approximately 0.5 to 1.5 mm, and in this embodiment, it is 0.5 mm.

[0054] Specifically, in the embodiment, the local transverse web of the normal section of the wall of the S-bend nozzle transition section including the web-type load-bearing structure is perpendicularly connected to the longitudinal webs on both sides of the symmetrical sections of the upper and lower walls, and its width and height are consistent with the width and height of the local transverse web at the nozzle outlet end. The thickness parameter of the local transverse web is approximately 0.5 to 1.5 mm, and 0.5 mm is taken in this embodiment; the axial distance of the local transverse web section relative to the outlet end is consistent with the axial length of the webs on both sides of the symmetrical section of the nozzle, that is, 550 mm.

[0055] Specifically, in this embodiment, the nozzle structure is fixedly supported and constrained at the upper and lower edges of the web, which can further reduce the structural deformation of the S-bend nozzle while maintaining the structural stress level of the nozzle within the engineering safety factor.

[0056] In this embodiment, titanium alloy is selected as the structural material, the total weight of the structure is 12.61 kg, and the weight of the web is 2.68 kg. After finite element simulation calculation, the deformation and stress distribution cloud diagram is as follows Figure 9 As shown in the figure, the analysis and calculation results show that the web structure's suppression of nozzle deformation can reduce the nozzle's maximum deformation to 4.38% of the original maximum deformation, meeting the structural deformation requirements. The maximum structural stress is 457.15 MPa, far below the yield limit of the titanium alloy material, meeting the engineering strength requirements. At the same time, the total weight of the structure meets the lightweight design requirements, demonstrating the effectiveness of the web-type load-bearing structure designed in this invention.

[0057] Although the embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and are not to be construed as limitations on the present invention. A person skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention.

Claims

1. An S-bend nozzle comprising a web-type load-bearing structure, characterized in that: The S-bend nozzle is divided into a nozzle convergence section, a transition section and a nozzle outlet and other straight sections along the axial direction, and its outer wall is coupled with a web-type load-bearing structure; The web-type load-bearing structure includes a first longitudinal web located on the symmetrical section of the S-bend nozzle and second longitudinal webs located on both sides of the symmetrical section. The first longitudinal web extends axially from the nozzle outlet to the nozzle inlet. Local transverse webs are provided on the nozzle outlet section and the normal section of the transition section wall. The local transverse webs on the nozzle outlet section are perpendicularly connected to the longitudinal webs on both sides of the upper and lower walls. The first longitudinal web comprises a longitudinal web with a symmetrical section on the upper wall surface and a longitudinal web with a symmetrical section on the lower wall surface; the longitudinal webs on both sides of the upper wall surface of the nozzle start from the nozzle outlet end and extend forward to the normal section of the transition section wall surface; the longitudinal webs on both sides of the lower wall surface of the nozzle start from the nozzle outlet end and extend forward to the nozzle inlet end; The second longitudinal webs include two longitudinal webs arranged on the upper wall of the nozzle and two longitudinal webs arranged on the lower wall; the two longitudinal webs on the upper and lower walls are symmetrical and parallel to the symmetrical section of the S-bend nozzle.

2. The S-bend nozzle comprising a web-type load-bearing structure according to claim 1, characterized in that: The thicknesses of the upper and lower walls of the first longitudinal web are D3 and D4 respectively; the distance between the upper edge of the longitudinal web of the symmetrical section of the upper wall and the highest point of the upper wall of the nozzle is the height H3, and the distance between the lower edge of the longitudinal web of the symmetrical section of the lower wall and the lowest point of the lower wall of the nozzle is the height H4. The heights H3 and H4 account for 4% to 15% of the total length of the nozzle.

3. The S-bend nozzle comprising a web-type load-bearing structure according to claim 2, characterized in that: The distance between the upper edge of the longitudinal webs on both sides of the upper wall of the nozzle and the highest point of the upper wall of the nozzle is H3, the axial length X accounts for 50%-55% of the total length of the nozzle, the thicknesses are D5 and D6 respectively, and the distance W1 between the symmetrical section of the S-bend nozzle accounts for 15%-20% of the width of the nozzle outlet end.

4. The S-bend nozzle comprising a web-type load-bearing structure according to claim 3, characterized in that: The distance between the lower edges of the longitudinal webs on both sides of the lower wall of the nozzle and the lowest point of the lower wall of the nozzle is H4, the thicknesses are D7 and D8 respectively, and the distance W2 between the lower edges and the symmetrical section of the S-bend nozzle accounts for 15% to 20% of the width of the nozzle outlet end.

5. The S-bend nozzle comprising a web-type load-bearing structure according to claim 4, characterized in that: The height of the local transverse web on the cross section of the nozzle outlet end is consistent with the height of the longitudinal webs on both sides of the upper and lower walls. Its width L accounts for 40% to 50% of the width of the nozzle outlet end, and its thickness is D9.

6. The S-bend nozzle comprising a web-type load-bearing structure according to claim 5, characterized in that: The distance between the local transverse web structure on the normal section of the transition section wall and the nozzle outlet section is equal to the axial length X of the longitudinal webs on both sides of the nozzle upper wall. Its width and height are consistent with the local transverse web located at the nozzle outlet section. Its thickness is D 10 .

7. The S-bend nozzle comprising a web-type load-bearing structure according to claim 6, characterized in that: The local transverse webs include a left transverse web and a right transverse web, and adjacent edges of the left and right transverse webs are respectively connected to edges of the second longitudinal webs.

8. The S-bend nozzle comprising a web-type load-bearing structure according to claim 7, characterized in that: The thickness of each web in the web-type load-bearing structure is 0.5-1.5 mm.

9. Application of an S-bend nozzle comprising a web-type load-bearing structure as claimed in any one of claims 1 to 8 on a stealth aircraft, characterized in that: The upper and lower edges of the first longitudinal web, the second longitudinal web and the partial transverse web are respectively connected to the outer skin of the aircraft to limit the deformation of the nozzle structure in various directions.

Images