CN109668478B - Stable propulsion sabot for air cannon and design method thereof - Google Patents

Abstract

The invention discloses a stable propelling sabot for an air cannon and a design method thereof.A gap leakage amount of the sabot moving in a cannon barrel is reduced by processing grooves with different numbers and sizes on the outer side of a cylindrical sabot, and the gap between the sabot and the cannon barrel can be increased under the same gap leakage amount, so that the movement instability of the outer wall of the sabot and the inner wall of a cannon bore caused by interference of processing, impurities and the like is reduced, the loss of the sabot during launching under the same launching pressure is reduced, the design and machining difficulty is reduced, and the stable launching of the sabot is ensured; iteration and calculation are carried out on the two-dimensional sabot profile curve in a mode of formulating a gap leakage index target function, so that a sabot two-dimensional profile of a corresponding design gap leakage rate index parameter is obtained, and a stable propulsion sabot geometric shape is designed. The bullet support and the related design method can provide a high-efficiency stable-propulsion test technology support for various air cannon tests.

Description

Stable propelling sabot for air cannon and design method thereof

Technical Field

The invention relates to the technical field of air cannon launching test devices, in particular to a bullet holder used in an air cannon launching test.

Background

In the work of aviation engine part bird, ice impact, foreign object swallowing, blade loss, target shooting by a cartridge case, other impact dynamics tests and the like, a test technology that an air cannon launches a projectile to impact a target plate is needed, so that the adaptation of the projectiles of different types, sizes and shapes to the inner wall of the air cannon is ensured, and the stability of the accelerating process of the projectiles is ensured as much as possible. As described in chinese patent ZL 201310574270.9, a hollow bullet holder having a cylindrical outer shape is used as a bullet-and-cannon matching device. However, since friction exists between the projectile holder and the gun barrel, in addition, impurities, processing defects and the like on the outer wall of the projectile holder and the inner wall of the gun barrel are likely to interfere with each other when the gap is small, so that the propulsion is unstable, and when the gap is large, the gap leakage amount of the common projectile holder is large, so that the propulsion efficiency of the projectile holder is affected, the development of an efficient and stable propulsion projectile holder and a design method thereof is urgently needed.

Therefore, a new technical solution is needed to solve the above technical problems.

Disclosure of Invention

The invention designs a stable propelling sabot for an air cannon, which can effectively reduce the leakage amount of a gap between the sabot and a cannon barrel in the launching process by using a vortex formed in sudden expansion and sudden contraction of a gap through which airflow flows, or increase the gap under the same leakage amount, thereby improving the launching efficiency.

The invention also provides a method for designing the geometrical shapes of the missile supports in different shapes aiming at the gap leakage rate index.

In order to achieve the aim, the stable propelling sabot for the air cannon adopts the following technical scheme:

the utility model provides an air bubble is with stably promoting sabot, includes the columniform sabot body, be equipped with at least one annular slot on the surface of sabot body, the setting of this annular slot circumference is on the sabot body.

Furthermore, the bullet holds in the palm the body and has three parallel and the even annular groove that sets up each other, and the width and the degree of depth of these three annular grooves are all the same. The sabot is used in an air cannon and carries projectiles.

Has the beneficial effects that: according to the stably-propelled sabot for the air cannon, the grooves with different numbers and sizes are processed on the outer side of the cylindrical sabot, so that the gap leakage amount of the sabot moving in a cannon barrel is reduced, the gap between the sabot and the cannon barrel can be increased under the same gap leakage amount, the movement instability of the outer wall of the sabot and the inner wall of a cannon bore caused by interference of processing, impurities and the like is reduced, the loss of the sabot during launching under the same launching pressure is reduced, the design and machining difficulty is reduced, and the stable launching of the sabot is ensured.

The invention also provides an air cannon, which comprises the stable propelling sabot for the air cannon.

The design method of the bullet holder provided by the invention can adopt the following technical scheme:

the method comprises the following steps:

(1) setting initial design parameters, and designing a plurality of types of bullet holders, wherein the number of grooves and the width of the grooves on each type of bullet holder are different;

(2) analyzing, modeling, calculating and analyzing the clearance leakage amount of a plurality of different types of bullet holders to obtain the leakage amount of the different bullet holders;

(3) comparing the leakage amount of each type of bullet holder, and taking the bullet holder type with the minimum leakage amount as an initial design configuration;

(4) setting a leakage index of the projectile support with the initial design configuration as an initial target parameter for further iteration;

(5) setting design parameters of the geometrical shape of the bullet holder of the initial design configuration, including the distance between the grooves, the depth of the grooves and the width of the grooves, and calculating the gap leakage amount again;

(6) and comparing the calculation result of each step with a leakage index target function, if the error exceeds 1%, changing the initial design parameters, continuing to calculate, iterating until the error with the target parameter is less than 1%, and determining the geometric shape of the refined missile support.

The method for designing the bullet holder has the beneficial effects that iteration and calculation are carried out on the two-dimensional bullet holder profile curve in a mode of formulating the gap leakage index target function, so that the bullet holder two-dimensional profile of the corresponding designed gap leakage rate index parameter is obtained, and the stable propulsion bullet holder geometric shape is designed.

Drawings

FIG. 1 is a schematic diagram of a prior art sabot structure;

FIG. 2 is a schematic view of the structure of the bullet holder B of the present invention;

FIG. 3 is a schematic view of the structure of the bullet holder C of the present invention;

FIG. 4 is a schematic structural view of a bullet holder D of the present invention;

FIG. 5 is a graph comparing leakage in different sabots across a 0.1mm gap;

fig. 6 is a flowchart of a method for designing the sabot structure according to the present invention.

Detailed Description

Preferred embodiments of the apparatus and method of the present invention are described in further detail below with reference to the accompanying drawings.

Example one

This embodiment is an embodiment of a sabot structure.

Referring to fig. 2 to 4, the present invention discloses a stable propelling projectile holder for an air cannon, which is applied to the air cannon and carries a projectile. This bullet holds in palm includes the columniform bullet holds in the palm the body, be equipped with at least one annular slot on the surface of bullet support body, the setting of this annular slot circumference is on the bullet support body.

Specifically, as shown in fig. 2, the bullet holder body 1 has three parallel and uniformly arranged annular grooves 2, and the three annular grooves 2 have the same width and depth. The sabot structure is numbered as structure B in this embodiment. As shown in fig. 3, the bullet holder body 1 ' has four parallel annular grooves, two of the annular grooves 21 ' have the same width and depth, and the other two annular grooves 22 ' have a wider width than the other two annular grooves. The sabot structure is numbered C in this embodiment. As shown in fig. 4, the bullet holder body 1 has two parallel and uniformly arranged annular grooves, and the width of the two annular grooves 2' is greater than the width of the grooves in the structure B. The sabot structure is numbered D in this embodiment.

As shown in fig. 5, the leakage amount of different sabot structures is analyzed and counted, and compared with the sabot (such as the structure a in fig. 1), the structure B, the structure C, and the structure D in the prior art, the leakage amount is compared, and the sabot structure with the minimum leakage amount is the structure B. Let out leakage quantity little, can increase bullet support and gun barrel clearance under the same clearance leaks leakage quantity to reduce the motion instability that bullet support outer wall and bore inner wall lead to because of interference such as processing, impurity, reduce the loss when the bullet supports the transmission under the same transmitting pressure, reduce the design and the machining degree of difficulty, guarantee the bullet and hold in the palm the stable transmission. Therefore, the air cannon can adopt the stable propelling sabot for the air cannon.

Example two

This embodiment is an embodiment of a design method of a pop-up structure.

Referring to fig. 6, the method for designing a stable propelling sabot for an air cannon according to the present invention includes the following steps:

(1) setting initial design parameters, and designing a plurality of bullet supports, wherein the number of grooves and the width of the grooves on each bullet support are different;

(2) analyzing, modeling, calculating and analyzing the gap leakage amount of a plurality of different types of bullet holders to obtain the leakage amount of the different bullet holders;

(3) comparing the leakage amount of each type of bullet holder, and taking the bullet holder type with the minimum leakage amount as an initial design configuration;

(4) setting a leakage index of the projectile support with the initial design configuration as an initial target parameter for further iteration;

(5) setting design parameters of the geometrical shape of the bullet holder of the initial design configuration, including the distance between the grooves, the depth of the grooves and the width of the grooves, and calculating the gap leakage amount again;

(6) and comparing the calculation result of each step with a leakage index target function, if the error exceeds 1%, changing the initial design parameters, continuing to calculate, iterating until the error with the target parameter is less than 1%, and determining the geometric shape of the refined missile support.

The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the above examples are not intended to limit the present invention in any way, and all technical solutions obtained by means of equivalents or equivalent changes fall within the protection scope of the present invention.

Claims (1)

1. A design method of a stable propelling sabot for an air cannon is disclosed, wherein the sabot is applied to the air cannon and bears a projectile; this bullet holds in palm includes the columniform bullet and holds in the palm the body, be equipped with at least one annular slot on the surface of bullet support body, the setting of this annular slot circumference is on the bullet support body for increase bullet support and gun barrel clearance, its characterized in that includes following steps:

(1) setting initial design parameters, and designing a plurality of types of bullet holders, wherein the number of grooves and the width of the grooves on each type of bullet holder are different;

(2) analyzing, modeling, calculating and analyzing the gap leakage amount of a plurality of different types of bullet holders to obtain the leakage amount of the different bullet holders;

(3) comparing the leakage amount of each type of bullet holder, and taking the bullet holder type with the minimum leakage amount as an initial design configuration;

(4) setting a leakage index of the projectile support with the initial design configuration as an initial target parameter for further iteration;

(5) setting design parameters of the geometrical shape of the bullet holder of the initial design configuration, including the distance between the grooves, the depth of the grooves and the width of the grooves, and calculating the gap leakage amount again;

(6) and comparing the calculation result of each step with a leakage index target function, if the error exceeds 1%, changing the initial design parameters, continuing to calculate, iterating until the error with the target parameter is less than 1%, and determining the geometric shape of the refined missile support.

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