Passive on-orbit non-connection supporting structure of novel cold end

Abstract

The invention discloses a novel passive in-orbit non-connection supporting structure of a cold end. The passive in-orbit non-connection supporting structure comprises a cold end structure, a hot end structure and a transmitting tube structure. Wherein the cold end structure is connected with one end of the transmitting tube structure; and the other end of the transmitting tube structure is connected with the hot end structure. The thermal insulation performance and the structural stability of the non-connection supporting structure of the low-temperature storage tank of the on-orbit vehicle are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of carrier heat protection, and in particular relates to a new type of passive on-orbit non-connected support structure of a cold end. Background Art

[0002] The thermal insulation of cryogenic propellant tanks is of great significance in the long-term on-orbit operation of launch vehicles, and its thermal insulation effect affects the length of time the launch vehicle can operate on-orbit. As long-term on-orbit spacecraft are subject to harsh thermal environments, passive on-orbit non-connected support structures (PODS) have become an important means to reduce propellant evaporation due to less heat leakage.

[0003] PODS can change the heat conduction path during the launch phase and the on-orbit phase, and achieve dynamic adjustment of mechanical loads and thermal loads under different conditions. During the launch phase, PODS is subjected to axial force, and the conical surface of the cold-end contact rod fits tightly with the contact nut and the cold-end body. The heat passes from the hot-end joint through the hot-end adjustment rod and the hot-end body to the launch tube, and then passes from the cold-end body through the cold-end contact rod and the contact nut in parallel to reach the cold-end joint. During the on-orbit phase, PODS is not subjected to axial force, and a certain gap is retained between the conical surface of the contact rod and the contact nut and the cold-end body. After reaching the launch tube, the heat must pass through the cold-end body, the adjustment bushing, the on-orbit tube and the cold-end contact rod before reaching the cold-end joint.

[0004] The cold end contact rod of PODS is designed with a gap of about 100 μm between the adjusting nut and the cold end body, the purpose of which is to isolate the heat conduction from the cold end body to the cold end joint. Once the adjusting bushing produces a lateral displacement relative to the cold end body, the gap may be destroyed, thus losing the heat insulation effect. This will not only reduce the heat protection performance of the cryogenic tank, but may also affect the on-orbit working time and efficiency of the entire spacecraft. The cold end body of the existing PODS is only connected to the adjusting bushing by threaded fitting, and the adjusting bushing assumes the function of fixing the on-orbit tube and the cold end contact rod. Its structure is shown in Figure 1(a) and Figure 1(b).

[0005] In order to reduce heat leakage on orbit, the connection between the adjustment bushing and the cold end body must be as few as possible, so the connection between the two is only achieved by threaded fit. Although this design can achieve axial fixation of the adjustment bushing, it cannot control the lateral position. The slight error of the thread may be amplified by factors such as the impact load during launch and the thermal cycle in the orbital environment, and it may also become loose after long-term use, causing the entire on-orbit tube part to tilt. Summary of the invention

[0006] The technical problem solved by the present invention is: to overcome the deficiencies of the prior art, to provide a new passive on-orbit non-connected support structure for the cold end, and to improve the thermal insulation performance and structural stability of the on-orbit carrier cryogenic tank non-connected support structure.

[0007] The object of the present invention is achieved through the following technical scheme: a new type of cold-end passive on-orbit non-connected support structure, comprising: a cold-end structure, a hot-end structure and a launch tube structure; wherein the cold-end structure is connected to one end of the launch tube structure; and the other end of the launch tube structure is connected to the hot-end structure.

[0008] In the above-mentioned new passive on-track non-connected support structure of the cold end, the cold end structure includes a cold end joint, a cold end contact rod, a cold end adjustment nut, an on-track pipe, a cold end end body, a cold end adjustment bushing and a small cold end fastening nut; wherein, the stud of the cold end joint is connected to the threaded hole of the cold end contact rod; the small cold end fastening nut is connected to the stud of the cold end joint, and the small cold end fastening nut is against the cold end contact rod; the internal thread of the cold end adjustment nut is connected to the external thread of the cold end contact rod, and one end face of the cold end contact rod is against the protruding part of the cold end body; the internal thread of the cold end body is connected to the tail stud of the cold end adjustment bushing; the cold end adjustment bushing is arranged at the center position of the cold end body; one end of the on-track pipe is connected to the cold end contact rod, and the other end of the on-track pipe is connected to the cold end adjustment bushing; the on-track pipe is located inside the cold end body.

[0009] In the above-mentioned novel passive on-track non-connected support structure of the cold end, the cold end structure further includes an on-track pipe clamp; wherein one end of the on-track pipe is connected to the cold end contact rod through the on-track pipe clamp.

[0010] In the above-mentioned new passive on-track non-connected support structure of the cold end, the cold end structure also includes a second on-track pipe clamp; wherein the other end of the on-track pipe is connected to the cold end adjustment bushing through the second on-track pipe clamp.

[0011] In the above-mentioned new passive on-orbit non-connected support structure of the cold end, the hot end structure includes a hot end joint, a hot end adjustment rod, a hot end body, a small hot end fastening nut and a large hot end fastening nut; wherein, the stud of the hot end joint is connected to the threaded hole of the hot end adjustment rod; the small hot end fastening nut is connected to the stud of the hot end joint, and the small hot end fastening nut is abutted against the hot end adjustment rod; the internal thread of the hot end body is connected to the external thread of the hot end adjustment rod; the large hot end fastening nut is connected to the hot end adjustment rod, and the large hot end fastening nut is abutted against the hot end body.

[0012] In the above-mentioned new passive on-orbit non-connected support structure of the cold end, the launch tube structure includes a first launch tube clamp, a launch tube and a second launch tube clamp; wherein one end of the launch tube is connected to the cold end structure through the first launch tube clamp; and the other end of the launch tube is connected to the hot end structure through the second launch tube clamp.

[0013] In the above-mentioned passive on-orbit non-connected support structure of the new cold end, the material of the cold end joint is Invar.

[0014] In the passive on-track non-connected support structure of the novel cold end, the material of the on-track pipe is glass fiber epoxy resin.

[0015] In the passive on-orbit non-connected support structure of the above-mentioned new cold end, the material of the launch tube is glass fiber epoxy resin.

[0016] In the above-mentioned novel passive on-track non-connected support structure of the cold end, the cold end adjustment bushing is connected to the cold end body through an adjustment screw.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] (1) The present invention overcomes the problems of poor cold end fixation and heat resistance of existing PODS, and can provide more reliable lateral support performance through an improved cold end connection method, thereby improving the thermal insulation performance and structural stability of the non-connected support structure of the on-orbit vehicle cryogenic tank;

[0019] (2) The present invention controls the axial load and heat conduction of the support structure through an elastic glass fiber epoxy resin tube, thereby achieving heat conduction path adjustment under different acceleration conditions. The support structure not only meets the mechanical properties of high acceleration during launch, but also meets the high thermal resistance performance under the thermal cycle conditions of on-orbit flight. Through experimental verification, the structure of the present invention exhibits excellent thermal insulation performance at both liquid nitrogen and liquid helium temperatures, and exhibits good adjustment function in mechanical load tests;

[0020] (3) The improved cold end body and the adjusting bushing of the present invention can keep the relative position fixed by adjusting screws, and the stable and uniform gap can maintain thermal resistance and achieve extremely low heat leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0022] FIG. 1( a ) is a schematic diagram of a prior art in which a certain gap is left between the cold end contact rod, the adjusting nut and the cold end body;

[0023] FIG. 1( b ) is a schematic diagram of a prior art in which a cold end body and an adjusting bushing are connected only by threads;

[0024] Figure 2is a schematic diagram of a passive on-orbit non-connected support structure of a novel cold end provided by an embodiment of the present invention;

[0025] FIG3( a ) is a schematic diagram of a cold end structure provided by an embodiment of the present invention;

[0026] FIG3( b ) is an enlarged schematic diagram of the left dotted box in FIG3( a );

[0027] FIG3( c ) is an enlarged schematic diagram of the right dashed box in FIG3( a );

[0028] Figure 4 is a schematic diagram of a hot end structure provided by an embodiment of the present invention;

[0029] Figure 5 It is a schematic diagram of a transmitting tube structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0030] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0031] Figure 2 Schematic diagram of a passive on-orbit non-connected support structure of a new cold end provided by an embodiment of the present invention. Figure 2 As shown, the passive on-orbit non-connected support structure of the new cold end includes: a cold end structure 1, a hot end structure 2 and a launch tube structure 3; wherein the cold end structure 1 is connected to one end of the launch tube structure 3; and the other end of the launch tube structure 3 is connected to the hot end structure 2.

[0032] As shown in Fig. 3(a), Fig. 3(b) and Fig. 3(c), the cold end structure 1 includes a cold end joint 4, a cold end contact rod 5, a cold end adjustment nut 6, an on-rail tube 8, a cold end end body 9, a cold end adjustment bushing 10 and a cold end small fastening nut 11; wherein, the stud of the cold end joint 4 is connected to the threaded hole of the cold end contact rod 5; the cold end small fastening nut 11 is connected to the stud of the cold end joint 4, and the cold end small fastening nut 11 is against the cold end contact rod 5; the cold end adjustment The internal thread of the section nut 6 is connected to the external thread of the cold end contact rod 5, and one end face of the cold end contact rod 5 is against the protruding part of the cold end body 9; the internal thread of the cold end body 9 is connected to the tail stud of the cold end adjustment bushing 10; the cold end adjustment bushing 10 is arranged at the center position of the cold end body 9; one end of the rail pipe 8 is connected to the cold end contact rod 5, and the other end of the rail pipe 8 is connected to the cold end adjustment bushing 10; the rail pipe 8 is located inside the cold end body 9.

[0033] The cold end joint 4 cooperates with the threaded hole of the cold end contact rod 5 through the stud, and the relative position of the two is fixed by the small cold end fastening nut 11. The cold end adjustment nut 6 cooperates with the external thread of the cold end contact rod 5 through the internal thread, and the end face of the thicker side thereof abuts against the protruding part of the cold end body 9. The cold end body 9 cooperates with the stud at the tail of the cold end adjustment bushing 10 through the internal thread. In order to improve the effect of the cold end adjustment bushing and the adjustment bushing in controlling the roll and ensure that the reserved gap is uniform, the cold end adjustment bushing 10 is fixed to the center position of the cold end body 9 through two rows of staggered adjustment screws, a total of 6 in total. One end of the rail tube 8 is fixed to the cold end contact rod 5 through the rail tube clamp, and the other end is fixed to the cold end adjustment bushing 10 through the rail tube clamp.

[0034] The reserved gap Δd between the cold end adjusting nut 6 and the cold end body 9 is constrained in position as follows:

[0035]

[0036] Where: L is the length of the cold end body, ε is the strain of the cold end body, σ is the stress of the cold end body, E is the elastic modulus of the cold end body material, F is the force acting on the cold end body, and S is the cross-sectional area of ​​the cold end body.

[0037] Effect: This formula ensures that the design value Δd is maintained between the cold end adjusting nut 6 and the cold end body 9, and their relative positions are fixed.

[0038] As shown in FIG. 3( b ), the cold end structure 1 further includes an on-rail pipe clamp 7 ; wherein one end of the on-rail pipe 8 is connected to the cold end contact rod 5 via the on-rail pipe clamp 7 .

[0039] As shown in FIG. 3( c ), the cold end structure 1 further includes a second on-track pipe clamp 72 ; wherein the other end of the on-track pipe 8 is connected to the cold end adjustment bushing 10 via the second on-track pipe clamp 72 .

[0040] like Figure 4 As shown, the hot end structure 2 includes a hot end joint 12, a hot end adjusting rod 13, a hot end body 14, a small hot end fastening nut 15 and a large hot end fastening nut 16; wherein, the stud of the hot end joint 12 is connected to the threaded hole of the hot end adjusting rod 13; the small hot end fastening nut 15 is connected to the stud of the hot end joint 12, and the small hot end fastening nut 15 is abutted against the hot end adjusting rod 13; the internal thread of the hot end body 14 is connected to the external thread of the hot end adjusting rod 13; the large hot end fastening nut 16 is connected to the hot end adjusting rod 13, and the large hot end fastening nut 16 is abutted against the hot end body 14.

[0041] The hot end joint 12 is connected to the threaded hole with a smaller diameter at the thick end of the hot end adjusting rod 13 through a stud, and the relative positions of the two are fixed by a small hot end fastening nut 15; the hot end body 14 is connected to the external thread at the thin end of the hot end adjusting rod 13 through an internal thread, and the relative positions of the two are fixed by a large hot end fastening nut 16.

[0042] The hot end adjustment rod has a threaded hole and an external thread. The threaded hole cooperates with the external thread of the hot end joint and is fixed in position by an adjusting nut. The external thread cooperates with the threaded hole of the hot end body and is fixed in position to the external support platform by an adjusting nut. The hot end body clamps the launch tube through a clamp.

[0043] like Figure 5 As shown, the launch tube structure 3 includes a first launch tube clamp 17, a launch tube 18 and a second launch tube clamp 172; wherein one end of the launch tube 18 is connected to the cold end structure 1 through the first launch tube clamp 17; and the other end of the launch tube 18 is connected to the hot end structure 2 through the second launch tube clamp 172. The first launch tube clamp and the second launch tube clamp are both made of invar. The launch tube is made of glass fiber epoxy resin.

[0044] The cold end joint 4 is made of Invar. The on-track tube 8 is made of glass fiber epoxy resin. The launch tube 18 is made of glass fiber epoxy resin. The cold end adjustment bushing 10 is connected to the cold end body 9 through an adjustment screw.

[0045] The hot end can be stably connected to the external normal temperature support platform using the joint, and the hot end length can be precisely adjusted using the adjustment rod.

[0046] The cold end joint is connected to the cold end body through the cold end contact rod, both of which are made of Invar. The cold end joint is connected to the low-temperature storage tank. The contact nut fixes the cold end body and the contact rod and maintains the gap between them. The cold end body and the adjusting bushing are fixed by 6 adjusting screws, with 3 screws arranged equidistantly in the front and rear groups and 3 screws in the rear groups and the two groups of pins arranged in an alternating manner. The cold end body and the adjusting bushing are connected by a clamping ring on the track tube.

[0047] Before the rocket is launched, PODS fixes the cryogenic tanks on the support platform in groups of two, for a total of three groups.

[0048] During rocket launch, PODS is subjected to a large axial pressure load. The launch tube 18 is compressed, causing the tail of the cold end body to contact the tail of the hot end body, generating a large axial stress to counteract the load. The reserved gap between the cold end adjustment nut 6 and the cold end body 9 can also be compressed, further increasing the stress. Through the compression of materials and gaps, PODS can provide fixed support for the cryogenic tank during launch.

[0049] When the spacecraft is working in orbit, PODS is subjected to a small axial pressure load. The launch tube 17 is not compressed, so there is no contact between the cold end structure 1 and the hot end structure 2. The reserved gap between the cold end adjustment nut 6 and the cold end body 9 is maintained at the design value of 0.102mm under the control of the adjustment screw, and heat conduction on a larger contact surface is also avoided. Since PODS is in a vacuum and radiation-free environment, the heat leakage of the entire rod only comes from the heat conduction of the contact part of the rod, so unnecessary heat leakage can be effectively reduced.

[0050] This embodiment overcomes the problems of poor fixation and heat resistance of the existing PODS cold end. The improved cold end connection method can provide more reliable lateral support performance, improve the thermal insulation performance and structural stability of the non-connected support structure of the low-temperature tank of the on-orbit carrier; this embodiment controls the axial load and heat conduction of the support structure through an elastic glass fiber epoxy resin tube, and realizes the adjustment of the heat conduction path under different acceleration conditions. The support structure not only meets the mechanical properties of high acceleration during the launch process, but also meets the high thermal resistance performance under the thermal cycle conditions of on-orbit flight. Through experimental verification, the structure of this embodiment shows excellent thermal insulation performance at both liquid nitrogen and liquid helium temperatures, and shows good adjustment function in mechanical load tests; this embodiment can keep the relative position fixed through the improved cold end body and the adjustment bushing through the adjustment screw, and the stable and uniform gap can maintain thermal resistance and achieve extremely low heat leakage.

[0051] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. A new type of passive on-orbit non-connected support structure for the cold end, characterized in that include: A cold end structure (1), a hot end structure (2) and a launch tube structure (3); wherein, The cold end structure (1) is connected to one end of the launch tube structure (3); The other end of the launch tube structure (3) is connected to the hot end structure (2).

2. The novel passive on-track non-connected support structure of the cold end according to claim 1 is characterized in that: The cold end structure (1) comprises a cold end joint (4), a cold end contact rod (5), a cold end adjustment nut (6), an on-track tube (8), a cold end body (9), a cold end adjustment bushing (10) and a cold end small fastening nut (11); wherein, The stud of the cold end joint (4) is connected to the threaded hole of the cold end contact rod (5); The small cold end fastening nut (11) is connected to the stud of the cold end joint (4), and the small cold end fastening nut (11) abuts against the cold end contact rod (5); The internal thread of the cold end adjusting nut (6) is connected to the external thread of the cold end contact rod (5), and one end surface of the cold end contact rod (5) abuts against the protruding portion of the cold end body (9); The internal thread of the cold end body (9) is connected to the tail stud of the cold end adjustment bushing (10); The cold end adjustment bushing (10) is arranged at the center position of the cold end body (9); One end of the on-track pipe (8) is connected to the cold end contact rod (5), and the other end of the on-track pipe (8) is connected to the cold end adjustment bushing (10); The on-track pipe (8) is located inside the cold end body (9).

3. The novel passive on-track non-connected support structure of the cold end according to claim 2 is characterized in that: The cold end structure (1) further comprises an on-track pipe clamp (7); wherein one end of the on-track pipe (8) is connected to the cold end contact rod (5) via the on-track pipe clamp (7).

4. The novel passive on-track non-connected support structure of the cold end according to claim 2 is characterized in that: The cold end structure (1) further comprises a second on-track pipe clamp (72); wherein the other end of the on-track pipe (8) is connected to the cold end adjustment bushing (10) via the second on-track pipe clamp (72).

5. The novel passive on-track non-connected support structure of the cold end according to claim 1 is characterized in that: The hot end structure (2) comprises a hot end joint (12), a hot end adjustment rod (13), a hot end body (14), a hot end small fastening nut (15) and a hot end large fastening nut (16); wherein, The stud of the hot end joint (12) is connected to the threaded hole of the hot end adjustment rod (13); The hot end small fastening nut (15) is connected to the stud of the hot end joint (12), and the hot end small fastening nut (15) abuts against the hot end adjustment rod (13); The internal thread of the hot end body (14) is connected to the external thread of the hot end adjustment rod (13); The hot end large fastening nut (16) is connected to the hot end adjusting rod (13), and the hot end large fastening nut (16) abuts against the hot end body (14).

6. The novel passive on-track non-connected support structure of the cold end according to claim 1 is characterized by: The launch tube structure (3) comprises a first launch tube clamp (17), a launch tube (18) and a second launch tube clamp (172); wherein: One end of the launch tube (18) is connected to the cold end structure (1) via the first launch tube clamp (17); The other end of the launch tube (18) is connected to the hot end structure (2) via the second launch tube clamp (172).

7. The novel passive on-track non-connected support structure of the cold end according to claim 2 is characterized by: The material of the cold end joint (4) is Invar.

8. The novel passive on-track non-connected support structure of the cold end according to claim 2 is characterized by: The material of the on-track tube (8) is glass fiber epoxy resin.

9. The novel passive on-track non-connected support structure of the cold end according to claim 6 is characterized by: The material of the transmitting tube (18) is glass fiber epoxy resin.

10. The novel cold end passive on-track non-connected support structure according to claim 2 is characterized in that: The cold end adjustment bushing (10) is connected to the cold end body (9) via an adjustment screw.

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