A reusable rocket tail main engine movable annular protection device

Abstract

This application relates to a movable annular protective device for the main engine at the tail of a reusable rocket, comprising a rocket body, several main engines, and an annular protective cover disposed at the tail section of the rocket body. The annular protective cover surrounds the outer wall of the tail section of the rocket body and is connected to the outer wall of the rocket body through several drive mechanisms, which drive the annular protective cover to retract or extend along the axial direction of the rocket body. This application has the following foreseeable technical effects: the device can greatly reduce the aerodynamic load torque of the main engine servo system during the reentry phase, significantly reducing the design difficulty of the main engine servo system, thereby reducing the development cost of the reusable rocket; the structure is simple, does not occupy the limited space inside the rocket body, and further improves the carrying capacity; and its compact placement on the outer wall of the rocket body facilitates the installation, operation, and maintenance of the rocket body.

Description

Technical Field

[0001] This invention belongs to the aerospace field and relates to the design of reusable rockets, specifically a reusable rocket tail main engine movable annular protection device. Background Technology

[0002] With the continuous advancement of global aerospace technology, the space economy is booming. Space "new infrastructure," represented by large-scale low-Earth orbit internet and communication satellite constellations, has become an important national development direction. It is projected that in the next 5 to 10 years, the dense networking and maintenance launches of satellite constellations will create significant market demand for launch vehicles, particularly low-cost launch vehicles. Internationally, SpaceX's Falcon 9 launch vehicle, through reusability, has significantly reduced launch costs, accumulating launch orders exceeding $10 billion and promoting the development of the space economy. Reusability is a crucial way to reduce costs, and developing reusable launch vehicles will greatly enhance my country's ability to access and utilize space.

[0003] The reentry phase of a recoverable rocket requires multiple activations of the main engine for braking and deceleration. The main engine thrust chamber directly faces the high-speed incoming flow, and the recovered rocket body will experience a high Mach number and high dynamic pressure reentry environment. The main engine servo system will bear enormous load torque, placing stringent design requirements on the system and resulting in significant design challenges and high costs. Therefore, it is necessary to design a protective device for the main engine's movement at the tail of the reusable rocket to reduce the load torque borne by the main engine servo system during the reentry phase. Summary of the Invention

[0004] To address the shortcomings or improvement needs of the existing technology, this invention provides a movable annular protection device for the main engine at the tail of a reusable rocket. This device can greatly reduce the aerodynamic load torque of the main engine servo system during the reentry phase, significantly reduce the design difficulty of the main engine servo system, and reduce the development cost of the reusable rocket.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A reusable rocket tail main engine movable annular protection device includes a rocket body, several main engines, and an annular protective cover disposed at the tail section of the rocket body.

[0007] The annular protective cover surrounds the outer wall of the tail section of the arrow body and is connected to the outer wall of the arrow body through several driving mechanisms. The driving mechanisms drive the annular protective cover to retract or extend along the axis of the arrow body.

[0008] Preferably, the drive mechanism includes a linear servo and a connecting rod. The linear servo is fixedly mounted on the outer wall of the arrow body, and one end of the connecting rod is fixedly connected to the output end of the linear servo, while the other end is fixedly connected to the annular protective cover.

[0009] Preferably, the linear servos are evenly distributed circumferentially along the axial direction of the arrow body.

[0010] Preferably, when the annular protective cover is in a retracted state, its lower end face is flush with the bottom end face of the tail section of the arrow body.

[0011] Preferably, the height of the annular protective cover is greater than or equal to the length of the main engine at the tail of the rocket body.

[0012] Preferably, the thickness of the annular protective cover is 5-10 mm.

[0013] In summary, the above-mentioned one or more technical solutions provided in this application can produce at least the following beneficial effects or advantages:

[0014] 1. This device can greatly reduce the aerodynamic load torque of the main engine servo system during the reentry phase, significantly reduce the design difficulty of the main engine servo system, and reduce the development cost of reusable rockets;

[0015] 2. The structure is simple and does not occupy the limited space inside the rocket, further improving the carrying capacity;

[0016] 3. Its compact design on the outer wall of the rocket body facilitates installation, operation, and maintenance. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the movable annular protection device for the main tail engine of a reusable rocket in one embodiment of this application;

[0018] Figure 2 for Figure 1 Side view;

[0019] Figure 3 This is a schematic diagram of the extended state of the movable annular protective device of the main engine at the tail of a reusable rocket in one embodiment of this application;

[0020] Figure 4 for Figure 3 Side view;

[0021] Figure 5 This is a schematic diagram of the fully extended movable annular protective device for the main tail engine of a reusable rocket in one embodiment of this application.

[0022] Figure 6 for Figure 5 Side view.

[0023] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0024] 1-Rocket body, 2-Annular protective cover, 3-Main engine, 4-Linear servo, 5-Connecting rod. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0026] In the description of this invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, in the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0027] like Figures 1 to 6 As shown, the present invention provides a movable annular protective device for the main engines at the tail of a reusable rocket, comprising a rocket body, several main engines, and an annular protective cover disposed at the tail section of the rocket body. In this embodiment, seven main engines are connected in parallel, and the annular protective cover surrounds the outer wall of the tail section of the rocket body. It is connected to the outer wall of the rocket body through at least three sets of drive mechanisms, and the drive mechanisms drive the annular protective cover to retract or extend along the axial direction of the rocket body.

[0028] The drive mechanism includes linear servos and connecting rods. In this embodiment, four sets of linear servos and connecting rods are evenly arranged circumferentially along the axial direction of the arrow body. Each linear servo is fixedly installed on the outer wall of the arrow body. One end of each connecting rod is fixedly connected to the output end of the linear servo, and the other end is fixedly connected to the annular protective cover. When the servo mechanism built into the linear servo controls the retraction or extension of its output end, the connecting rod connected to the output end drives the annular protective cover to retract or extend along the axial direction of the arrow body.

[0029] To ensure the aerodynamics of the rocket body remains unaffected, when the annular protective shield is in its retracted state, its lower end face is flush with the bottom end face of the rocket's tail section, and the height of the annular protective shield is greater than or equal to the length of several main engines at the tail of the rocket body. Simultaneously, while ensuring the structural strength of the annular protective shield, its weight is minimized as much as possible. The thickness of the annular protective shield is 5-10 mm; in this embodiment, the thickness is 5 mm; in another embodiment, the thickness is 7 mm; and in yet another embodiment, the thickness is 10 mm.

[0030] The method of using the movable annular protective device for the main engine at the tail of the reusable rocket in this application is as follows: When the reusable rocket ignites and takes off, the annular protective shield at the tail of the reusable rocket is in a retracted state, with its lower end face flush with the bottom end face of the tail section, to prevent interference between the main engine and the annular protective shield during swinging. After the recovered rocket body separates from the second stage rocket, the annular protective shield for the main engine at the tail of the reusable rocket continues to remain in a retracted state.

[0031] After entering the return phase, when the recovered rocket body returns to an altitude below 50 kilometers, the linear servo motor can activate the annular protective shield of the rocket's tail section. At this time, the main engines do not swing and maintain a 0° swing angle to prevent interference between the main engines and the annular protective shield. Under the protection of this device, the rocket's main engines will not generate large aerodynamic load torque during the high dynamic pressure return phase.

[0032] Using Ansys CFX simulation software, the simulation results are shown in Table 1 below. The maximum aerodynamic load torque data of the reentry stage main engine servo under multiple states of the movable annular protection device for the main engine of the reusable rocket tail section in this application are as follows. It can be seen from the table that after adding the movable annular protection device, the maximum aerodynamic load torque of the reentry stage main engine servo is significantly reduced when the annular protective cover extends to different lengths. When the annular protective cover extends to 900 mm, the aerodynamic load torque at different angles of attack decreases by more than 83% compared with the original state.

[0033] Table 1 Comparison of Maximum Aerodynamic Load Torque in the Main Engine Reentry Phase

[0034]

[0035] In summary, the movable annular protective device for the main engine at the tail of the reusable rocket, as described in this application, is in a retracted state during the ascent and reentry phases when the main engine is running. The annular protective device adheres to the outer wall of the tail section of the rocket body and does not affect the main engine's oscillation operation. During the aerodynamic deceleration in the reentry phase, the linear servo motor actuates, and the annular protective cover extends outward, forming an annular protective cover outside the main engine. At this time, the main engine does not oscillate and maintains a 0° oscillation angle. Under the protection of the movable annular protective device, the aerodynamic load torque of the main engine's thrust chamber is significantly reduced, substantially lowering the design requirements for the load torque of the main engine servo system.

[0036] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A reusable rocket tail main engine movable annular protection device, comprising a rocket body and several main engines, characterized in that, It also includes a ring-shaped protective cover located at the tail section of the arrow body. The annular protective cover surrounds the outer wall of the tail section of the arrow body and is connected to the outer wall of the arrow body through at least three sets of drive mechanisms. The drive mechanisms drive the annular protective cover to retract or extend along the axis of the arrow body. When the annular protective cover is in a retracted state, its lower end face is flush with the bottom end face of the tail section of the arrow body; The height of the annular protective cover is greater than or equal to the length of the main engine at the tail of the rocket body; The thickness of the annular protective cover is 5-10 mm; The drive mechanism includes a linear servo and a connecting rod. The linear servo is fixedly mounted on the outer wall of the arrow body. One end of the connecting rod is fixedly connected to the output end of the linear servo, and the other end is fixedly connected to the annular protective cover.

2. The reusable rocket tail main engine movable annular protection device according to claim 1, characterized in that: The linear servos are evenly distributed circumferentially along the axis of the rocket body.

Images