A rocket jet test structure

Abstract

This invention provides a rocket jet test structure, including a support rod, a connector, a projectile body, a balance, a high-pressure pipe, a tail section, a gas chamber, a nozzle I, a nozzle II, a nozzle seat, and a support rod. One end of the support rod is connected to an external gas source pipeline, and the other end is connected to the balance, the support rod, and the high-pressure pipe, introducing the external gas source into the high-pressure pipe. The connector is sleeved on the outside of the support rod, with both ends fixedly connected to an external wind tunnel test mechanism and the support rod, respectively. The projectile body, tail section, and nozzle seat simulate the shape of a rocket shell. One end of the projectile body mates with the conical surface of the balance, and the other end is connected to the tail section. The other end of the tail section is sealed by the nozzle seat, on which a nozzle II that does not participate in the jet is installed. The high-pressure pipe, the gas chamber, and the support rod are located within the cavity formed by the projectile body, tail section, and nozzle seat. The high-pressure pipe is connected to the gas chamber, and the support rod is fixedly connected to the gas chamber. The nozzle I that participates in the jet is fixed at the end of the gas chamber. The support rod, the high-pressure pipe, the gas chamber, and the nozzle I form a complete gas path. The gas introduced from the support rod flows through the pipeline and is ejected from the nozzle I.

Description

Technical Field

[0001] This invention belongs to the field of wind tunnel test model design technology, and specifically relates to a rocket jet test structure. Background Technology

[0002] The concept of rocket recovery technology was proposed as early as the 1960s, but it remained unrealized due to technological limitations and economic factors. It wasn't until the 21st century, with the rise of private space companies, that rocket recovery technology saw new development opportunities. After the first-stage rocket completes its mission, the engine ignites and reverses the jet flow, causing the first-stage rocket to descend slowly. Accurately predicting the direct force and interference forces of the jet flow is crucial for successful rocket recovery. Currently, research on the jet flow field and interference mainly employs two methods: numerical simulation and wind tunnel testing. However, due to the numerous influencing factors, numerical simulation struggles to accurately reflect real-world conditions.

[0003] Work on rocket jet wind tunnel testing has not yet been fully carried out. Due to the limitations of wind tunnel size, the scaled-down rocket model is relatively small, posing significant challenges to its structural design. The scaled-down model requires a sealed high-pressure gas path (except for the nozzle outlet) to support the jet test. The model shell must not contact the high-pressure gas path, and the gap should be greater than 2.5 mm. Simultaneously, the high-pressure pipeline needs to be secured to prevent violent vibrations caused by airflow impact, which could collide with the model shell and affect measurement data. The high-pressure gas path must possess sufficient strength to meet the design specifications for high-pressure vessels. Furthermore, a stable balance needs to be installed within the small-sized scaled-down rocket model to meet load measurement requirements. These design considerations further complicate the model's structural design. During the rocket jet wind tunnel test, different roll angle test states and different nozzle jet configurations need to be implemented to complete the experiment. Summary of the Invention

[0004] In order to overcome the shortcomings of the existing technology, the inventors have conducted intensive research and provided a rocket jet test structure that solves the problems of constructing a stable high-pressure gas path and assembling various components in a small space in a scaled-down rocket model, and realizes the simulation of different roll angle test states and different nozzle jet states of the model.

[0005] The technical solution provided by this invention is as follows:

[0006] A rocket jet test structure includes a support rod, a joint, a projectile body, a balance, a high-pressure pipe, a tail section, a gas chamber, nozzle I, nozzle II, a nozzle seat, and a support rod;

[0007] The support rod has a hollow pipe structure, with one end connected to an external air source pipe and the other end connected to the balance, support rod and high-pressure pipe, introducing the external air source into the high-pressure pipe;

[0008] The joint is a hollow shell structure, sleeved on the outside of the support rod. One end is connected to the external wind tunnel testing mechanism, and the other end is fixed to the support rod by a pin.

[0009] The missile body, tail section, and nozzle mount simulate the shape of a rocket casing. One end of the missile body mates with the balance cone surface, and the other end connects to the tail section. The other end of the tail section is sealed by the nozzle mount, which is equipped with nozzle II. Nozzle II simulates the nozzle that does not participate in the air jet during rocket recovery.

[0010] The high-pressure pipe, gas chamber, and support rod are located in the cavity formed by the missile body, tail section, and nozzle seat; the high-pressure pipe is connected to the gas chamber, and the support rod is fixed to the gas chamber; the nozzle I is fixed at the end of the gas chamber, simulating the nozzle that participates in the jet spray during rocket recovery. The support rod, high-pressure pipe, gas chamber, and nozzle I form a complete gas path. The gas introduced from the support rod flows through the pipeline and is ejected from the nozzle I.

[0011] The rocket jet test structure provided by the present invention has the following beneficial effects:

[0012] (1) The present invention provides a rocket jet test structure, which adjusts the roll angle test state of the rocket jet test structure by means of the assembly of support rods and joints.

[0013] (2) The rocket jet test structure provided by the present invention forms a complete high-pressure gas path through a support rod, a high-pressure pipe, a gas chamber and a nozzle. The support rod and the high-pressure pipe are threaded together. The high-pressure pipe and the gas chamber adopt a conical-spherical fit and are tightened with a nut. The nozzle and the gas chamber are threaded together, which can realize the construction of a high-pressure closed gas path (except for the nozzle outlet).

[0014] One end of the high-pressure pipe is connected to the support rod, and the other end is connected to the air chamber. The support of the high-pressure pipe and the support rod ensures that the entire high-pressure gas pipeline has sufficient rigidity.

[0015] (3) The present invention provides a rocket jet test structure in which the body, tail section and nozzle seat simulate the shape of the rocket shell. The model shell formed by the body, tail section and nozzle seat does not contact the internal components and nozzle I and meets the set gap size, so as to avoid vibration affecting the stability of the high pressure gas path during the test.

[0016] (4) The rocket jet test structure provided by the present invention can measure the load on the model during the test by fixing one end of the balance to the support rod and the other end to the conical surface of the projectile body and tightening it with bolts.

[0017] (5) The rocket jet test structure provided by this invention has three nozzle mounting holes on the rear section of the gas chamber, and is designed with three plugs and three sets of nozzle seats. When simulating a jet-free state, the three nozzle mounting holes of the gas chamber are all blocked with plugs, and the first set of nozzle seats is installed on the tail section. When simulating a single-nozzle jet, the two nozzle mounting holes of the gas chamber are all blocked with plugs, a nozzle I is installed on one nozzle mounting hole, and the second set of nozzle seats is installed on the tail section. When simulating a three-nozzle jet, a nozzle I is installed on the three nozzle mounting holes of the gas chamber, and the third set of nozzle seats is installed on the tail section. Through the design of the gas chamber and nozzle seats, the three states of three-nozzle jet, single-nozzle jet, and no jet are successfully realized. Attached Figure Description

[0018] Figure 1 This is an overall cross-sectional view of the rocket jet test structure of the present invention;

[0019] Figure 2 This is a schematic diagram of the support rod and connection of the present invention;

[0020] Figure 3 This is a schematic diagram of the air chamber structure of the present invention;

[0021] Figure 4 This is a schematic diagram of the air chamber structure of the present invention;

[0022] Figure 5 This is a schematic diagram of the air chamber connection structure of the present invention;

[0023] Figure 6 This is a schematic diagram of the nozzle assembly of the present invention;

[0024] Figure 7 This is a schematic diagram of the three sets of nozzle seats of the present invention. From top to bottom, they are the first set of nozzle seats, the second set of nozzle seats and the third set of nozzle seats. The blue and purple nozzles are nozzles I. Detailed Implementation

[0025] The features and advantages of the present invention will become clearer and more apparent from the following detailed description.

[0026] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0027] This invention provides a rocket jet test structure, such as Figure 1 As shown, it includes a support rod 1, a connector 2, a projectile body 3, a balance 4, a high-pressure pipe 5, a tail section 6, an air chamber 7, a nozzle I 8, a nozzle II 12, a nozzle seat 9, and two support rods 10.

[0028] Support rod 1 is a hollow pipe structure. One end is connected to an external air source pipe, and the other end is connected to balance 4, two support rods 10 and high-pressure pipe 5, so that the external air source is introduced into the high-pressure pipe 5.

[0029] The connector 2 is a hollow shell structure, which is sleeved on the outside of the support rod 1. One end is connected to the external wind tunnel test mechanism, and the other end is fixed to the support rod 1 through a pin.

[0030] The side walls of support rod 1 and joint 2 are machined with multiple sets of pin holes, or support rod 1 is machined with a set of cancellation holes and the side wall of joint 2 is machined with multiple sets of pin holes, or support rod 1 is machined with multiple sets of cancellation holes and the side wall of joint 2 is machined with a set of pin holes. Rotating support rod 1 forms different sets of cancellation holes to complete the adjustment of the roll angle test state of the rocket jet test structure.

[0031] The projectile body 3, tail section 6, and nozzle mount 9 simulate the shape of a rocket casing. One end of the projectile body 3 mates with the conical surface of the balance 4 and is tightened by bolts, while the other end connects to the tail section 6. The other end of the tail section 6 is sealed by the nozzle mount 9, on which a nozzle II 12 is installed. The nozzle II 12 simulates a nozzle that does not participate in the airflow during rocket recovery. The model casing formed by the projectile body 3, tail section 6, and nozzle mount 9 does not contact the internal components and nozzle I 8 and meets the set clearance dimensions to avoid vibration affecting the stability of the high-pressure gas path during testing.

[0032] The high-pressure pipe 5, the gas chamber 7, and the support rod 10 are located in the cavity formed by the projectile body 3, the tail section 6, and the nozzle seat 9. The high-pressure pipe 5 is connected to the gas chamber 7 and is tightened by a nut. The support rod 10 is fixed to the gas chamber 7 by bolts and is used to support the gas chamber 7. The nozzle I 8 is fixed at the end of the gas chamber 7. The nozzle I 8 simulates the nozzle that participates in the jet spray during rocket recovery. The support rod 1, the high-pressure pipe 5, the gas chamber 7, and the nozzle I 8 form a complete high-pressure gas path. The gas introduced from the support rod 1 flows through the pipeline and is ejected from the nozzle I 8.

[0033] Airflow is allowed inside support rod 1, preventing the circuit of balance 4 from being led out from inside support rod 1. A hole, such as a 45° hole, is made at the support rod corresponding to the tail end of the balance to allow the circuit of balance 4 to be led out from outside support rod 1.

[0034] like Figure 2 As shown, one end of the support rod 1 is connected to the balance 4, two support rods 10, and the high-pressure pipe 5. The balance 4 is located below the central axis of the support rod 1, and the high-pressure pipe 5 is located above the central axis of the support rod 1. The two support rods 10 are symmetrically distributed on both sides of the central axis of the support rod 1. The support rod 1 and the balance 4 are fitted with a tapered surface, and the support rod 1 and the support rods 10 are connected by threads. The support rod 1 and the high-pressure pipe 5 are also connected by threads.

[0035] An axial threaded hole is machined on the end face of the support rod 1 to mate with the high-pressure pipe 5; the axial threaded hole is coaxial with the high-pressure pipe 5 but not coaxial with the support rod 1, and the depth of the axial threaded hole is sufficient to form a sufficient air passage from the end of the support rod to the end of the nozzle.

[0036] like Figure 3 and Figure 4 As shown, the air chamber 7 includes a nut 701, a nozzle 702, a front section 703, a middle section 704, a rear section 705, and two sleeves 706, which are connected as a whole by welding. The nut 701, nozzle 702, front section 703, middle section 704, and rear section 705 are connected sequentially. The end of the nozzle 702 that connects to the high-pressure pipe 5 is conical, while the end of the high-pressure pipe 5 that connects to the nozzle 702 is spherical. Tightening the nut 701 tightly seals the two surfaces, forming a seal. The front section 703 and the middle section 704, and the middle section 704 and the rear section 705 form two inner cavities. The airflow is rectified through these two cavities, ensuring consistent air pressure at all points exiting the air chamber 7. The sleeve 706 passes through the front section 703, the middle section 704, and the rear section 705 of the air chamber. Both ends are connected to the front section 703 and the rear section 705 of the air chamber by welding. The support rod 10 passes through the sleeve 706 and is fixed to the air chamber 7 by the bolt 11 at the tail end, thus completing the rigid connection between the support rod 1 and the air chamber 7.

[0037] like Figure 5 As shown, support rod 1 is rigidly connected to air chamber 7 via support rod 10, and is connected to air chamber 7 via high-pressure pipe 5. The two support rods 10 and high-pressure pipe 5 enable precise installation and positioning of air chamber 7. The high-pressure air circuit of the rocket jet test structure needs to have sufficient rigidity to prevent collision between the rocket shell and the high-pressure pipeline. The support of the high-pressure pipe and support rod ensures that the entire high-pressure air circuit has sufficient height.

[0038] like Figure 6 As shown, to simulate the three states of rocket recovery—three-nozzle jet flow, one-nozzle jet flow, and no jet flow—three nozzle mounting holes are provided on the rear section 705 of the gas chamber 7, along with three plugs and three sets of nozzle seats 9. Figure 7 The first set of nozzle mounts does not have through holes to avoid nozzle I 8, and the number of nozzles II 12 installed on it is equal to the total number of actual rocket nozzles. The second set of nozzle mounts has one through hole to avoid nozzle I 8, and the number of nozzles II 12 installed on it differs from the total number of actual rocket nozzles by one. The third set of nozzle mounts has three through holes to avoid nozzle I 8, and the number of nozzles II 12 installed on it differs from the total number of actual rocket nozzles by three. When simulating a no-jet flow state, all three nozzle mounting holes of the gas chamber 7 are sealed with plugs, and the first set of nozzle mounts is installed on the tail section 6. When simulating a one-nozzle jet flow, both nozzle mounting holes of the gas chamber 7 are sealed with plugs, nozzle I 8 is installed on one nozzle mounting hole, and the second set of nozzle mounts is installed on the tail section 6. When simulating a three-nozzle jet flow, nozzle I 8 is installed on all three nozzle mounting holes of the gas chamber 7, and the third set of nozzle mounts is installed on the tail section 6.

[0039] The nozzle I 8 is connected to the rear section 705 of the air chamber. The second and third sets of nozzle seats have through holes to avoid the nozzle I 8. A retaining ring 801 is designed on the side of the nozzle I 8 near the nozzle outlet. The retaining ring 801 is close to the through holes on the second and third sets of nozzle seats and has a diameter larger than the diameter of the through holes on the second and third sets of nozzle seats, which can minimize the entry of external airflow into the model cavity.

[0040] The first set of nozzle mounts does not involve avoiding the nozzle I 8 and can be designed as an integral structure or a split structure. In order to facilitate the installation of the second and third sets of nozzle mounts, the second and third sets of nozzle mounts are spliced ​​structures, such as splitting them in two along the centerline. After the nozzle I 8 is installed on the rear section 705 of the air chamber, the second and third sets of nozzle mounts are then assembled to the tail section 6.

[0041] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

[0042] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A rocket jet test structure, characterized in that, It includes a support rod (1), a connector (2), a projectile body (3), a balance (4), a high-pressure pipe (5), a tail section (6), an air chamber (7), a nozzle I (8), a nozzle II (12), a nozzle seat (9), and a support rod (10); The support rod (1) is a hollow pipe structure. One end is connected to the external air source pipe, and the other end is connected to the balance (4), support rod (10) and high pressure pipe (5) to introduce the external air source into the high pressure pipe (5). The connector (2) is a hollow shell structure, which is sleeved on the outside of the support rod (1). One end is connected to the external wind tunnel test mechanism, and the other end is fixed to the support rod (1) through a pin. The projectile body (3), tail section (6) and nozzle seat (9) simulate the shape of a rocket shell. One end of the projectile body (3) is fitted with the conical surface of the balance (4), and the other end is connected to the tail section (6). The other end of the tail section (6) is sealed by the nozzle seat (9). Nozzle II (12) is installed on the nozzle seat (9). Nozzle II (12) simulates the nozzle that does not participate in the jetting during rocket recovery. The high-pressure pipe (5), the air chamber (7) and the support rod (10) are located in the cavity formed by the projectile body (3), the tail section (6) and the nozzle seat (9); the high-pressure pipe (5) is connected to the air chamber (7) and the support rod (10) is fixed to the air chamber (7); the nozzle I (8) is fixed at the end of the air chamber (7) to simulate the nozzle that participates in the jet during rocket recovery. The support rod (1), the high-pressure pipe (5), the air chamber (7) and the nozzle I (8) form a complete air path. The gas introduced from the support rod (1) flows through the pipeline and is ejected from the nozzle I (8).

2. The rocket jet test structure according to claim 1, characterized in that, The side walls of the support rod (1) and the joint (2) are machined with multiple sets of pin holes, or the support rod (1) is machined with a set of cancellation holes and the side walls of the joint (2) are machined with multiple sets of pin holes, or the support rod (1) is machined with multiple sets of cancellation holes and the side walls of the joint (2) are machined with a set of pin holes. Rotating the support rod (1) forms different sets of cancellation holes to complete the adjustment of the roll angle test state of the rocket jet test structure.

3. The rocket jet test structure according to claim 1, characterized in that, The support rod (1) is connected to the balance (4), the support rod (10) and the high-pressure pipe (5); the balance (4) is located below the central axis of the support rod (1), the high-pressure pipe (5) is located above the central axis of the support rod (1), and there are two support rods (10), which are symmetrically distributed on both sides of the central axis of the support rod (1).

4. The rocket jet test structure according to claim 1, characterized in that, The support rod (1) and the balance (4) are in conical fit, the support rod (1) and the support rod (10) are threaded, and the support rod (1) and the high pressure pipe (5) are threaded.

5. The rocket jet test structure according to claim 1, characterized in that, An axial threaded hole that mates with the high-pressure pipe (5) is machined on the end face of the support rod (1); the axial threaded hole is coaxial with the high-pressure pipe (5) but not coaxial with the support rod (1), and the depth of the axial threaded hole is sufficient to form a sufficient air passage from the end of the support rod to the end of the nozzle.

6. The rocket jet test structure according to claim 1, characterized in that, The air chamber (7) includes a nozzle (702), a front section (703), a middle section (704), a rear section (705), and a sleeve (706). The nozzle (702), the front section (703), the middle section (704), and the rear section (705) are connected in sequence. The nozzle (702) is connected to the high-pressure pipe (5). The front section (703) and the middle section (704), and the middle section (704) and the rear section (705) form two inner cavities. The airflow is rectified through the two inner cavities, so that the air pressure of the airflow flowing out from each position of the air chamber (7) is consistent.

7. The rocket jet test structure according to claim 6, characterized in that, The end of the connector (702) connected to the high-pressure pipe (5) is a conical surface, and the end of the high-pressure pipe (5) connected to the connector (702) is a spherical surface. The conical surface and the spherical surface are tightly fitted together by tightening the nut (701) outside the connector (702) to form a seal.

8. The rocket jet test structure according to claim 1, characterized in that, The gas chamber (7) has three nozzle mounting holes and is equipped with three plugs and three sets of nozzle seats (9). The first set of nozzle seats does not have a through hole to avoid the nozzle I (8), and the number of nozzles II (12) installed on it is equal to the total number of actual rocket nozzles. The second set of nozzle seats has a through hole to avoid the nozzle I (8), and the number of nozzles II (12) installed on it is 1 less than the total number of actual rocket nozzles. The third set of nozzle seats has three through holes to avoid the nozzle I (8), and the number of nozzles II (12) installed on it is 3 less than the total number of actual rocket nozzles. When simulating a no-jet flow state, all three nozzle mounting holes of the air chamber (7) are sealed with plugs, and the first set of nozzle seats is installed on the tail section (6); when simulating a one-nozzle jet flow, both nozzle mounting holes of the air chamber (7) are sealed with plugs, nozzle I (8) is installed on one nozzle mounting hole, and the second set of nozzle seats is installed on the tail section (6); when simulating a three-nozzle jet flow, nozzle I (8) is installed on the three nozzle mounting holes of the air chamber (7), and the third set of nozzle seats is installed on the tail section (6).

9. The rocket jet test structure according to claim 8, characterized in that, The nozzle I (8) is connected to the air chamber (7). The second set of nozzle seats and the third set of nozzle seats have through holes to avoid the nozzle I (8). The nozzle I (8) is designed with a retaining ring (801) on the side near the nozzle outlet. The retaining ring (801) is close to the through holes on the second set of nozzle seats and the third set of nozzle seats, and its diameter is larger than the diameter of the through holes on the second set of nozzle seats and the third set of nozzle seats.

10. The rocket jet test structure according to claim 8, characterized in that, The second set of nozzle seats and the third set of nozzle seats are spliced ​​structures. After the nozzle I (8) is installed on the air chamber (7), the second set of nozzle seats and the third set of nozzle seats are then assembled to the tail section (6).

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