Large-aperture-ratio fiber winding composite material shell structure

Abstract

The invention relates to the technical field of solid rocket engine combustion chamber composite material shells, and provides a large-aperture-ratio fiber winding composite material shell structure which comprises a front sealing head, a barrel section, a front skirt and a rear skirt assembly. The front sealing head is connected with one end of the cylinder section, the front skirt sleeve is arranged on the front sealing head and extends to the outside of one end of the cylinder section, and the other end of the cylinder section is connected with the rear skirt assembly. A traditional end socket is omitted, stable winding forming of the large-aperture-ratio composite material winding shell is achieved, and the requirement that the composite material shell bears the high internal pressure load effect is met. According to the structure, a traditional composite shell forming wire hanging tool and a combustion chamber shell skirt structure are combined, the structure and the function are integrated, the problem of fiber wire sliding during winding of a large-aperture-ratio structure is solved, the manufacturability of winding forming of the large-aperture-ratio composite shell is greatly improved, and the internal pressure bearing capacity of the large-opening composite shell is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solid rocket engine combustion chamber composite shell, in particular to a large aperture ratio fiber winding composite shell structure. BACKGROUND

[0002] Light weight, high energy, vector propulsion is the development trend of modern solid rocket engine. Composite shell technology is suitable for the lightweight of solid rocket engine. By using high specific strength fiber composite material, the negative mass of the engine can be effectively reduced, and the specific impulse ratio can be improved.

[0003] Multi-nozzle solid rocket engine is suitable for thrust vector control of solid rocket engine. The multi-nozzle structure requires that the combustion chamber shell has a larger radial opening size. Therefore, the composite shell is required to have a large opening structure.

[0004] The opening diameter of the composite shell head, i.e. the size of the polar hole, determines the size of the fiber winding angle at both ends of the shell. A large opening corresponds to a large winding angle, and a small opening corresponds to a small winding angle. The polar hole ratio of the conventional composite shell is the same or similar, so the winding angles at the front and rear ends are the same or similar, and the winding process is good. In the case of small change in winding angle, there will be no problems such as yarn slipping in the variable-angle winding process. However, the polar hole ratio of the large opening composite combustion chamber shell is quite different, and the winding angle changes greatly at the front and rear ends during variable-angle winding. On the one hand, it is easy to cause yarn slipping problems; on the other hand, a large change in winding angle requires sufficient length of the combustion chamber shell to realize the transition of the winding angle. In addition, when the aperture ratio is too large, the axial width of the head arc segment is narrow, which reduces the connection strength of the head end and affects the pressure-bearing capacity of the combustion chamber shell. SUMMARY

[0005] In view of the defects in the prior art, the purpose of the present application is to provide a large aperture ratio fiber winding composite shell structure.

[0006] According to the large aperture ratio fiber winding composite shell structure provided by the present application, the front head, the barrel segment, the front skirt, and the rear skirt assembly are included. The front head is connected to one end of the barrel segment, the front skirt is sleeved on the front head and extends to the outside of one end of the barrel segment, and the other end of the barrel segment is connected to the rear skirt assembly.

[0007] Preferably, the front head includes an outer winding part, a front joint, and a first rubber heat insulation layer, the first rubber heat insulation layer is arranged on part or all of the inner surface of the front joint and is pre-sulfurized and molded with the front joint, and the outer winding part is arranged on the outer surface of the front joint.

[0008] Preferably, the barrel segment comprises a second fiber-wound composite material layer and a second rubber heat insulation layer; The composite material is wound on the second rubber heat insulation layer and cured to form the second fiber-wound composite material layer.

[0009] Preferably, the rear skirt assembly comprises a rear skirt and a hanging wire pin, the rear skirt is uniformly provided with a plurality of pin holes in the circumferential direction, and the hanging wire pin is configured as a whole with the rear skirt through the pin holes.

[0010] Preferably, the inside of the rear skirt is configured with a third rubber heat insulation layer, and the outside of the rear skirt is a third fiber-wound composite material layer.

[0011] Preferably, the composite material on the third fiber-wound composite material layer extends to the rear skirt and is wound back around the hanging wire pin, and after the winding is completed, the third fiber-wound composite material layer is cured to form.

[0012] Preferably, the front skirt comprises a first shape-fitting sleeve segment and a first connecting segment, an inner wall of one end of the first shape-fitting sleeve segment is provided with a tapered surface for sleeving and connecting with one end of the barrel segment, the other end of the first shape-fitting sleeve segment is connected with the first connecting segment, and the wall thickness of the first connecting segment is greater than that of the first shape-fitting sleeve segment, and the first connecting segment is used for connecting the outside.

[0013] Preferably, the front skirt is a hollow cylinder of metal material, and the first shape-fitting sleeve segment is a hollow cylinder.

[0014] Preferably, the front joint is a metal joint and is a solid disc.

[0015] Preferably, the front head is an ellipsoidal structure, and the outer layer winding part is a first fiber-wound composite material layer obtained by winding a composite material on the outer surface of the front joint and curing.

[0016] Compared with the prior art, the present application has the following beneficial effects: The present application cancels the traditional head, realizes stable winding and forming of the large-aperture-ratio composite material wound shell, and meets the requirements of the composite material shell under high internal pressure load. The structure combines the traditional composite shell forming hanging wire tooling and the combustion chamber shell skirt structure, integrates structure and function, avoids fiber wire sliding problem in winding of large-aperture-ratio structure, greatly improves the process of winding and forming of large-aperture-ratio composite material shell, and improves the internal pressure bearing capacity of large-opening composite material shell. BRIEF DESCRIPTION OF DRAWINGS

[0017] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings: Figure 1A cross-sectional schematic diagram of a fiber-wound composite shell structure with a large aperture ratio; Figure 2 This is a schematic diagram of the front skirt structure; Figure 3 This is a schematic diagram of the front end cap structure; Figure 4 This is a schematic diagram of the front connector. Figure 5 This is a structural schematic diagram of the rear skirt assembly; Figure 6 This is a structural diagram of the hanging pin.

[0018] The diagram shows: Front end cap 1; Outer winding portion 11; Front connector 12; First rubber insulation layer 13; Segment 2; Second rubber insulation layer 21; Front skirt 3; First conformal socket section 31; First connecting segment 32; Back skirt component 4; Back skirt 41; Second conformal socket section 411; Pin connecting section 412; Second connecting segment 413; Hanging pin 42. Detailed Implementation

[0019] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0020] Example 1: like Figure 1 As shown, this invention provides a large-pore-ratio fiber-wound composite material shell structure. The combustion chamber shell is a structure with a closed front end and a large open rear end, comprising: a front end cap 1, a cylindrical section 2, a front skirt 3, and a rear skirt assembly 4; as shown... Figure 1 As shown, the front end cap 1 is connected to one end of the cylindrical section 2, the front skirt 3 is fitted onto the front end cap 1 and extends to the outside of one end of the cylindrical section 2, and the other end of the cylindrical section 2 is connected to the rear skirt assembly 4.

[0021] like Figure 3As shown, the front head 1 is an ellipsoid structure with a small opening, and the aperture is relatively small. The front head 1 includes an outer winding portion 11, a front joint 12, and a first rubber thermal insulation layer 13. The center of the front head 1 is the front joint 12. The front joint 12 is a metal joint and is a solid disc-shaped structure, which is used as a clamping for the winding machine during the winding process. The first rubber thermal insulation layer 13 is arranged on part or all of the inner surface of the front joint 12 and is pre-vulcanized and formed with the front joint 12. The outer winding portion 11 is arranged on the outer surface of the front joint 12. The outer winding portion 11 is a first fiber winding composite material layer obtained by winding a composite material on the outer surface of the front joint 12 and curing and forming.

[0022] As shown in FIG. 1, Figure 1 As shown in FIG. 2, the barrel segment 2 includes a second fiber winding composite material layer and a second rubber thermal insulation layer 21. The second fiber winding composite material layer is obtained by winding a composite material on the second rubber thermal insulation layer 21 and curing and forming.

[0023] As shown in FIG. 3, Figure 1 , Figure 5 As shown in FIG. 4, the rear skirt assembly 4 includes a rear skirt 41 and a wire hanging pin 42. The rear skirt 41 is uniformly provided with a plurality of pin holes in the circumferential direction. The wire hanging pin 42 is combined with the rear skirt 41 as a whole through the pin holes. The wire hanging pin 42 is made of high-strength metal material, which improves the shear and bending resistance and avoids the separation of the rear skirt assembly 4 from the fiber winding shell under the internal pressure. The inner side of the rear skirt 41 is a third rubber thermal insulation layer, and the outer side of the rear skirt 41 is a third fiber winding composite material layer. The composite material on the third fiber winding composite material layer extends to the rear skirt 41 and is wound back after passing through the wire hanging pin 42. Specifically, the fiber is wound from the barrel segment 2 to the end of the rear skirt 41, wound back after passing through the wire hanging pin 42, and then wound back to complete the wire hanging. After the winding is completed, the third fiber winding composite material layer is obtained by curing and forming. In the present application, the rear end of the combustion chamber shell is a large opening, and the rear head structure is cancelled, and the connection requirements with other assemblies are met by the rear skirt 41.

[0024] Further, the cross section of the wire hanging pin 42 in the rear skirt assembly 4 is an ellipse, as shown in FIG. 5. The long axis direction is parallel to the shell axis, which improves the bearing capacity. One end of the wire hanging pin 42 is an elliptical cylinder segment, which cooperates with the pin groove of the rear skirt 41. The other end is an elliptical cone segment, which facilitates the fiber to slide into the adjacent pin circumferential gap during the winding process. Figure 6

[0025] After curing and forming, the wire hanging pin 42 protrudes outside the third fiber winding composite material layer. Then, the protruding part of the pin is removed by machining, so as to ensure the outer shape of the shell.

[0026] As shown in FIG. 6, Figure 2 ​As shown, the front skirt 3 is made of metal material, hollow cylindrical, including two parts, respectively, the first type of sleeve segment 31 and the first connecting segment 32, the first type of sleeve segment 31 is hollow cylindrical, the inner wall of one end of the first type of sleeve segment 31 is provided with a tapered surface, used for connecting with one end of the cylinder segment 2, the other end of the first type of sleeve segment 31 is connected with the first connecting segment 32, the wall thickness of the first connecting segment 32 is greater than that of the first type of sleeve segment 31, and the first connecting segment 32 is used for connecting the outside.

[0027] As shown, Figure 5 As shown, the rear skirt 41 is made of metal material, hollow cylindrical, and is divided into three segments according to functions; one end close to the cylinder segment 2 is the second type of sleeve segment 411, the inner wall of the second type of sleeve segment 411 is provided with a tapered surface, the tapered surface of the second type of sleeve segment 411 is connected with the second rubber heat insulation layer 21 designed in the form of sleeve, so as to realize the smooth transition of the inner diameter of the cylinder segment 2 and the inner diameter of the large pole hole; the middle is the pin connecting segment 412, used for installing the wire hanging pin 42; the outermost is the second connecting segment 413, used for connecting the outside.

[0028] The first connecting segment 32 and the second connecting segment 413 are uniformly provided with stress grooves.

[0029] The front skirt 3 in the application is connected with other components of the engine by using the ring flange connection structure, and the ring flange is uniformly provided with bolt connection through holes and positioning pin holes; the rear skirt 41 is connected with other components of the engine by using the threaded structure; the front skirt 3 and the rear skirt 41 are all designed to have sealing grooves matched with other components, the shell structure has the general characteristics of the composite material shell, the shell winding layer is a fiber reinforced resin matrix composite material; the front skirt 3, the rear skirt 41 and the joint are made of metal material; the wire hanging pin 42 is made of high-strength metal material; the inner surface of the shell is the rubber heat insulation layer 21, the fiber winding composite material layer is a carbon fiber / epoxy resin composite material, the joint and the pin are preferably made of titanium alloy or super high-strength steel material, and the front and rear skirts 41 are preferably made of high-strength aluminum alloy.

[0030] The application combines the composite shell winding wire hanging tool with the combustion chamber shell rear skirt 41, cancels the rear end cover structure in the traditional combustion chamber shell winding, realizes the stable winding forming of the large aperture ratio combustion chamber shell, and meets the requirements of the combustion chamber shell under the action of high internal pressure load. The structure adopts the wire hanging pin 42, the composite material of the cylinder segment extends to the rear skirt 41, passes through the wire hanging pin 42, and is folded back to be wound, and the fiber winding composite material layer is obtained after solidification after the winding is completed. The rear end cover structure is cancelled, the winding angle only changes when the front end cover 1 transitions to the cylinder segment 2, the winding angle adjustment from the cylinder segment 2 to the rear end cover end is reduced, the fiber yarn sliding problem caused by the too large front and rear pole hole ratio is avoided, the problem of insufficient connection strength caused by the large rear end aperture ratio is solved, and the internal pressure bearing capacity of the large aperture ratio combustion chamber shell is improved.

[0031] Specifically, before winding, a rubber heat insulation layer 21 is laid on the sand core mold, then a front joint 12 and a skirt assembly are respectively installed at the front end and the rear end, and after completion, pre-vulcanization is performed; a fiber winding process is performed, the front head 1 is wound to a predetermined thickness, then the front skirt 3 is sleeved to the outside of the head, a subsequent winding process is performed, and after the winding is completed, it is integrally cured and formed; after forming, the protruding part of the hanging pin 42 is removed by machining to obtain a complete fiber winding combustion chamber shell.

[0032] Embodiment 2: This embodiment is a preferred example of embodiment 1, in this embodiment, the outer diameter of the combustion chamber shell cylinder segment 2 is 175.8mm, the winding layer thickness is 2mm, the total length of the shell is 477.7mm, and one end is closed and one end is large opening. The closed end metal joint column segment has a diameter of 5mm, the disc-shaped outer edge has a diameter of 50mm, and the material is selected to be 30CrMnSiA.

[0033] The inner profile diameter of the shell ball head is 148.6mm, and the inner profile diameter of the heat insulation layer is 147.6mm; the inner profile diameter of the rear end opening is 161.75mm, and the hole diameter ratio is 0.94.

[0034] Further, the front skirt 3 and the rear skirt 41 are both hollow cylindrical aluminum alloy metal materials, the first profile-matching sleeving segment 31 is designed with an axial long strip-shaped groove, the groove is radially penetrated, and 20 circumferential distribution is made, so that the front skirt 3 and the rear skirt 41 are ring-shaped combs, which is beneficial to the sleeving of the front skirt 3 and the rear skirt 41 and the matching of the rigidity of the fiber winding shell. The first connecting segment 32 of the front skirt 3 is circumferentially distributed with 12 countersunk through holes, and the rear skirt 41 is provided with M165.5 internal threads for connecting with the remaining engine components.

[0035] Further, the hanging pin 42 has a total height of 14mm, the bottom 11.5mm is an elliptical cylinder segment, the long axis of the cross section is 4.5mm, and the short axis is 3mm; the top 2.5mm is a frustum segment, the topmost cross section of the frustum segment has a long axis of 3mm and a short axis of 1.5mm. The material is selected to be 30CrMnSiA, the allowable tensile stress is 1080MPa, the allowable shear stress is 648MPa, and the shear stress and bending normal stress borne by the pin under the condition of 12.5MPa pressure are satisfied. The pin connecting segment 412 of the rear skirt 41 is circumferentially distributed with 100 elliptical cross-section sink grooves, the long axis of the cross section is 4mm, and the short axis is 3mm, which cooperates with the installation of the aforementioned 100 hanging pins 42.

[0036] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0037] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the specific embodiments described above, and various changes or modifications can be made by those skilled in the art within the scope of the claims, which do not affect the essential content of the present application. The embodiments of the present application and the features in the embodiments can be arbitrarily combined with each other in the case of no conflict.

Claims

1. A filament wound composite shell structure of large aspect ratio, characterised in that, The front head (1), the barrel segment (2), the front skirt (3), and the rear skirt assembly (4); The front head (1) is connected with one end of the barrel segment (2), the front skirt (3) is sleeved on the front head (1) and extends to the outside of one end of the barrel segment (2), and the other end of the barrel segment (2) is connected with the rear skirt assembly (4).

2. The fiber-wound composite pressure vessel structure of claim 1, wherein, The front head (1) comprises an outer layer winding part (11), a front joint (12), and a first rubber heat insulation layer (13), the first rubber heat insulation layer (13) is arranged on part or all of the inner surface of the front joint (12) and is pre-vulcanized and formed with the front joint (12), and the outer layer winding part (11) is arranged on the outer surface of the front joint (12).

3. The fiber-wound composite pressure vessel structure of claim 1, wherein, The barrel segment (2) comprises a second fiber winding composite material layer and a second rubber heat insulation layer (21). The second fiber winding composite material layer is obtained by winding and curing composite material on the second rubber heat insulation layer (21).

4. The fiber-wound composite pressure vessel structure of claim 3, wherein, The rear skirt assembly (4) comprises a rear skirt (41) and a wire hanging pin (42), the rear skirt (41) is uniformly provided with a plurality of pin holes in the circumferential direction, and the wire hanging pin (42) is arranged as a whole with the rear skirt (41) through the pin holes.

5. The fiber-wound composite pressure vessel structure of claim 4, wherein, The inner side of the rear skirt (41) is provided with a third rubber heat insulation layer, and the outer side of the rear skirt (41) is a third fiber winding composite material layer.

6. The fiber-wound composite pressure vessel structure of claim 5, wherein, The composite material on the third fiber winding composite material layer extends to the rear skirt (41), passes around the wire hanging pin (42), is folded back and wound, and the third fiber winding composite material layer is obtained by curing after the winding is completed.

7. The fiber-wound composite pressure vessel structure of claim 1, wherein, The front skirt (3) comprises a first shape-fitting sleeve segment (31) and a first connecting segment (32), the inner wall of one end of the first shape-fitting sleeve segment (31) is provided with a tapered surface for sleeving and connecting with one end of the barrel segment (2), the other end of the first shape-fitting sleeve segment (31) is connected with the first connecting segment (32), the wall thickness of the first connecting segment (32) is greater than that of the first shape-fitting sleeve segment (31), and the first connecting segment (32) is used for connecting the outside.

8. The fiber-wound composite pressure vessel structure of claim 7, wherein, The front skirt (3) is a hollow cylinder made of metal material, and the first shape-fitting sleeve segment (31) is a hollow cylinder.

9. The fiber-wound composite pressure vessel structure of claim 2, wherein, The front joint (12) is a metal joint and is a solid disc.

10. The fiber-wound composite pressure vessel structure of claim 2, wherein, The front head (1) is an ellipsoidal structure, and the outer layer winding part (11) is a first fiber winding composite material layer obtained by winding and curing composite material on the outer surface of the front joint (12).

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