Sounding rocket with automatic stage separation based on aerodynamic drag

Abstract

The present invention belongs to the technical field of sounding rockets, and provides a sounding rocket that realizes automatic stage separation based on aerodynamic drag. It includes a power stage and a payload stage. A plug-in tenon and mortise connection is adopted between the power stage and the payload stage, where the docking tenon is located at the head end of the power stage and the docking mortise is located at the tail end of the payload stage. In the present invention, at the end of the powered flight segment of the rocket, due to different cross-sectional areas between the power stage and the payload stage, under the action of aerodynamic drag, the axial acceleration of the power stage is less than the axial acceleration of the payload stage, realizing the automatic separation of the power stage and the payload stage, effectively reducing the energy loss during the inertial flight segment of the rocket, simplifying the existing rocket stage separation method, and effectively reducing the complexity of the sounding rocket stage separation system.

Description

Technical Field

[0001] The present invention belongs to the technical field of sounding rockets, and particularly relates to a sounding rocket that realizes automatic stage separation based on aerodynamic drag. Background Art

[0002] The near space generally refers to the region of 20 km to 120 km, covering the stratosphere, mesosphere, and lower thermosphere regions divided by temperature characteristics. There are complex atmospheric processes in this region, including photochemical processes, dynamic processes, ionization processes, phase change microphysical processes, etc., and there are also forced perturbations between the troposphere and the thermosphere. Therefore, near space exploration is of great significance to fields such as atmospheric science and atmospheric physics science.

[0003] The near space meteorological environment can be detected by technologies such as remote sensing and sounding rockets. Compared with remote sensing technology, although rocket detection has the deficiencies of not being reusable and unable to continuously observe for a long time, it is still an indispensable important means for near space atmospheric detection because it is the only method for in-situ detection in the near space. In-situ detection in the near space has been studied since the late 1940s. Currently, sounding rockets used for the near space mostly adopt single-stage rockets or two-stage powered rockets, but they have the following deficiencies: single-stage rockets usually have a large diameter and large aerodynamic drag in the inertial flight section; for two-stage powered rockets, the stage separation control system is complex and will increase the ineffective mass. With the increasing urgency of the demand for near space atmospheric environment detection, it is necessary to propose a sounding rocket that realizes automatic stage separation based on aerodynamic drag. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the sounding rocket of the present invention that realizes automatic stage separation based on aerodynamic drag utilizes the aerodynamic force at the end of the operation of the power stage to form a resistance difference between the payload stage and the power stage with different cross-sectional areas, so that the structure of the docking tenon and mortise is separated, realizing the automatic separation of the payload stage and the power stage, reducing the energy loss of the rocket during inertial flight, simplifying the existing rocket stage separation method, greatly reducing the complexity of the stage separation system, and improving the stability of rocket stage separation.

[0005] The present invention provides a sounding rocket that realizes automatic stage separation based on aerodynamic drag, which includes a power stage and a payload stage. The head end of the power stage is connected to the tail end of the payload stage by a plug-in tenon and mortise connection;

[0006] The plug-in tenon and mortise includes a docking tenon and a docking mortise. The docking tenon is located at the head end of the power stage, and the docking mortise is located at the tail end of the payload stage;

[0007] At the end of the powered flight stage of the rocket, due to the different cross-sectional areas between the powered stage and the payload stage, under the action of aerodynamic drag, the axial acceleration of the powered stage is less than that of the payload stage, realizing the automatic separation of the powered stage and the payload stage. The specific inter-stage separation is as follows:

[0008] If the axial acceleration of the powered stage is less than that of the payload stage , then there is:

[0009] ;

[0010] In the formula, m1 and m2 are the masses of the powered stage and the payload stage at the end of the active section of the rocket, A1 and A2 are the aerodynamic drag cross-sectional areas of the rocket powered stage and the payload stage, C d1 , C d2 are the drag coefficients of the rocket powered stage and the payload stage, g is the acceleration due to gravity, θ is the rocket elevation angle, ρ is the atmospheric density, v is the rocket axial velocity, and f is the static friction force between the docking socket and the docking tenon.

[0011] Preferably, if , set the ratio of the cross-sectional areas of the aerodynamic drag of the rocket powered stage and the payload stage to satisfy the following conditions:

[0012] ;

[0013] In the formula, is the ratio of the inter-stage frictional force to the aerodynamic cross-sectional drag of the payload stage, denoted as β. The drag cross-section A1 of the rocket powered stage is the area of its outer diameter cross-section minus the cross-section blocked by the payload stage at the docking location. The ratio of the blocked cross-section at the docking location to the payload stage cross-section is λ, , where is the blocked cross-section at the docking location.

[0014] Preferably, the following relationship exists between the outer diameter D1 of the powered stage and the outer diameter D2 of the payload stage:

[0015] ;

[0016] The following conditions are satisfied between the rocket payload stage and the powered stage:

[0017] .

[0018] Preferably, ignoring the influence of minor factors such as air buoyancy and Coriolis force, according to Newton's second law, at the end of the powered flight stage of the rocket, the mechanical equilibrium equations of the powered stage and the payload stage are:

[0019] .

[0020] Preferably, the docking tenon is made of high-strength material and can withstand the load during powered flight.

[0021] Preferably, a mortise and tenon structure is adopted for the connection between the payload stage and the power stage, and the docking mortise is arranged at the tail of the payload stage.

[0022] Preferably, tail fins are provided at the tails of both the payload stage and the power stage to jointly maintain the stability during the powered flight phase.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] The sounding rocket of the present invention realizes automatic stage separation based on aerodynamic drag. The automatic separation of the payload stage and the power stage is achieved through the drag difference formed by the aerodynamic force acting on the payload stage and the power stage with different cross-sectional areas when the power stage finishes working, reducing the energy loss during the inertial flight phase of the rocket, simplifying the existing stage separation method of the rocket, greatly reducing the complexity of the stage separation system, improving the reliability of rocket stage separation, and at the same time reducing the detection cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is the overall schematic diagram of the sounding rocket of the present invention that realizes automatic stage separation based on aerodynamic drag;

[0026] Figure 2 is the enlarged schematic diagram of the structure in the sounding rocket of the present invention that realizes automatic stage separation based on aerodynamic drag;

[0027] Figure 3 is the schematic diagram of the stage separation mechanism in the sounding rocket of the present invention that realizes automatic stage separation based on aerodynamic drag;

[0028] Figure 4 is the connection schematic diagram of the stage separation mechanism in the present invention;

[0029] Figure 5 is Figure 4 the enlarged schematic diagram at I in

[0030] Figure 6 is the structural schematic diagram of the docking mortise in the stage separation mechanism of the present invention;

[0031] Figure 7 is the structural schematic diagram of the docking tenon in the stage separation mechanism of the present invention.

[0032] MAIN REFERENCE MARKS:

[0033] 1, payload stage; 11, payload tail fin; 12, docking mortise; 2, power stage; 21, engine compartment section; 22, power tail fin; 23, docking tenon; 231, limit pin. DETAILED DESCRIPTION OF THE INVENTION

[0034] To elaborate on the technical content, structural features, achieved objectives and effects of the present invention, the following will be described in detail with reference to the accompanying drawings of the specification.

[0035] The sounding rocket of the present invention that realizes inter-stage automatic separation based on aerodynamic drag, as Figure 1 shown, includes a power stage 2 and a payload stage 1. The head end of the power stage 2 and the tail end of the payload stage 1 are connected by a plug-in tenon and mortise. The tail of the payload stage 1 is provided with payload tail fins 11 to ensure the stability of the payload stage 1 during inertial flight. The power stage 2 includes an engine compartment section 21 and power tail fins 22, etc. The power tail fins 22 are arranged at the tail end of the engine compartment section 21 through a connecting member.

[0036] As Figures 2 to 7 shown, the plug-in tenon and mortise includes a docking mortise 12 and a docking tenon 23. The docking tenon 23 is located at the head end of the inter-stage section of the power stage 2. A limit pin 231 is provided on the docking tenon 23 to restrict the relative rotation with the docking mortise 12 before separation. The docking mortise 12 is located at the tail end of the payload stage 1. The docking tenon 23 is made of a high-strength material and can withstand the loads during powered flight. When the aerodynamic drag acts on the payload stage 1 and the power stage 2 with different cross-sectional areas at the end of the powered flight section of the rocket, the axial acceleration of the payload stage 1 is greater than that of the power stage 2, realizing the automatic separation of the power stage 2 and the payload stage 1. The specific inter-stage separation is as follows:

[0037] If the axial acceleration of the power stage 2 is less than that of the payload stage 1 , then there is:

[0038] ;

[0039] In the formula, m1 and m2 are the masses of the power stage and the payload stage at the end of the active section of the rocket, A1 and A2 are the aerodynamic drag cross-sectional areas of the rocket power stage and payload stage, C d1 , C d2 are the drag coefficients of the rocket power stage and payload stage, g is the acceleration due to gravity, θ is the rocket elevation angle, ρ is the atmospheric density, v is the rocket axial velocity, and f is the static friction between the docking mortise 12 and the docking tenon 23.

[0040] If , set the ratio of the aerodynamic drag cross-sectional areas of the rocket power stage 2 and the payload stage 1 to satisfy the following conditions:

[0041] ;

[0042] In the formula, is the ratio of the inter-stage friction force to the aerodynamic cross-sectional resistance of the payload stage, denoted as β. The drag cross-sectional area A1 of the power stage is the area of its outer diameter cross-section minus the cross-section blocked by the payload stage at the docking part. The ratio of the blocked cross-section at the docking part to the cross-sectional area of the payload stage is λ, , where It is the shielding section at the docking part.

[0043] If the outer diameters of the power stage 2 and the payload stage 1 are D1 and D2 respectively, then it is:

[0044] 。

[0045] The following conditions are satisfied between the rocket payload stage 1 and the power stage 2:

[0046] 。

[0047] Neglecting the influence of small factors such as air buoyancy and Coriolis force, according to Newton's second law, at the end of the powered flight section of the rocket, the mechanical equilibrium equations of the power stage 2 and the payload stage 1 are:

[0048] 。

[0049] The following further describes the sounding rocket of the present invention for achieving inter-stage automatic separation based on aerodynamic drag in conjunction with embodiments:

[0050] The separation method of the sounding rocket for achieving inter-stage automatic separation based on aerodynamic drag includes the following steps:

[0051] S1. The diameter of the payload stage 1 is affected by the size of the built-in device. Usually, it will be determined first in the design, and then the power stage is designed with the diameter of the power stage being 3 times that of the payload stage 1, and then checked. If the separation conditions cannot be met, the mass of the payload stage 1 is adjusted to meet the separation requirements.

[0052] S2. The payload stage 1 and the power stage 2 are automatically separated under the action of the drag difference formed by the difference in the cross-sectional areas of the rocket body.

[0053] S3. The payload stage 1 continues to fly upward under the action of inertia to near the ballistic vertex, and the timing device starts to throw out the detection payload.

[0054] S4. The detection payload detects from top to bottom and transmits the detection data in real time, and the data is received and saved by the ground receiving device.

[0055] The sounding rocket of the present invention for achieving inter-stage automatic separation based on aerodynamic drag enables the docking tenon and mortise structure to be separated through the drag difference formed by the aerodynamic force acting on the payload stage 1 and the power stage 2 with different cross-sectional areas at the end of the operation of the power stage 2, thereby realizing the automatic separation of the payload stage 1 and the power stage 2, reducing the energy loss of the rocket during the inertial flight section, greatly reducing the complexity of the inter-stage separation system, improving the stability of the rocket inter-stage separation, and thus reducing the rocket cost.

[0056] The embodiments described above are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the spirit of the present invention's design, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A sounding rocket that realizes inter-stage automatic separation based on aerodynamic drag, characterized in that It includes a power stage and a payload stage, and the head end of the power stage and the tail end of the payload stage are connected by a pluggable mortise and tenon joint; The pluggable mortise and tenon joint includes a mating tenon and a mating mortise. The mating tenon is located at the head end of the power stage, and the mating mortise is located at the tail end of the payload stage; At the end of the powered flight segment of the rocket, due to the different cross-sectional areas between the power stage and the payload stage, under the action of aerodynamic drag, the axial acceleration of the power stage is less than that of the payload stage, realizing the automatic separation of the power stage and the payload stage. The specific inter-stage separation is as follows: If the axial acceleration of the power stage is less than the axial acceleration of the load stage , then there is: ； Where m1 and m2 are the masses of the power stage and the payload stage at the end of the active phase of the rocket, A1 and A2 are the aerodynamic drag cross-sectional areas of the power stage and the payload stage of the rocket, and C d1 , C d2 is the drag coefficient of the rocket power level and payload level, g is the acceleration of gravity, θ is the rocket elevation angle, ρ is the atmospheric density, v is the rocket axial velocity, and f is the static friction between the mortise and tenon; If , the cross-sectional area ratio of the aerodynamic resistance between the rocket power stage and the payload stage is set to satisfy the following conditions: ； In the formula, is the ratio of the inter-stage frictional force to the aerodynamic cross-sectional resistance of the load stage. Let it be β. The resistance cross-section A1 of the rocket power stage is the area obtained by subtracting the cross-section blocked by the load stage at the docking location from its outer diameter cross-section. The ratio of the blocked cross-section at the docking location to the cross-section of the load stage is λ. , where is the blocked cross-section at the docking location.

2. The sounding rocket for achieving inter-stage automatic separation based on aerodynamic drag according to claim 1, wherein Among them, the outer diameter D1 of the power stage and the outer diameter D2 of the payload stage have the following relationship: ； The following conditions are satisfied between the rocket payload stage and the power stage: 。 3. The sounding rocket for achieving automatic inter-stage separation based on aerodynamic drag according to claim 1, wherein Neglecting the influence of minor factors such as air buoyancy and Coriolis force, according to Newton's second law, at the end of the powered flight segment of the rocket, the mechanical equilibrium equations of the power stage and the payload stage are: 。 4. The sounding rocket for achieving inter-stage automatic separation based on aerodynamic drag according to claim 1, wherein The mating tenon is made of high-strength material and can withstand the loads during powered flight.

5. The sounding rocket for achieving inter-stage automatic separation based on aerodynamic drag according to claim 1, wherein The connection between the payload stage and the power stage adopts a mortise and tenon structure, and the mating mortise is arranged at the tail of the payload stage.

6. The sounding rocket for achieving inter-stage automatic separation based on aerodynamic drag according to claim 1, wherein, Tail fins are provided at the tails of both the payload stage and the power stage to jointly maintain the stability during the powered flight segment.

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