CN115143846A

CN115143846A - Method for rotating cannonball

Info

Publication number: CN115143846A
Application number: CN202210083533.5A
Authority: CN
Inventors: 陈清四
Original assignee: Longyan Chuanjing Electric Appliance Co ltd
Current assignee: Longyan Chuanjing Electric Appliance Co ltd
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2022-10-04

Abstract

The invention relates to a method for rotating a bullet. The method is characterized in that a gas injection channel is added on the bullet, so that the expansion gas generated by the explosion of gunpowder not only pushes the bullet or the bullet to advance, but also pushes the bullet or the bullet to rotate. The method can be used for designing and producing new shells and can also be used for improving the existing shells. The method is not only suitable for the bullet heads of guns with smooth inner walls, but also suitable for the shells of tanks, antiaircraft guns and the like with smooth inner walls and smooth bore barrels.

Description

Method for rotating cannonball

Technical Field

The invention relates to the field of weapon ammunition, in particular to a cannonball technology.

Background

Since the birth of the most primitive firearm, the related art of the cannonball is continuously developed by countries all over the world, and the corresponding products are various. The ballistic trajectory precision of the previous smoothbore gun barrel is poor, and in order to increase the shooting distance of the cannonball and ensure the shooting precision of the cannonball, the improved method is diversified. If the length of the gun barrel is increased, the length needs to be controlled within a certain range; the gun barrel is internally provided with the spiral rifling to enable the gun to rotate when the gun is popped out of the chamber, but the production process of the spiral rifling in the gun barrel is high, the rifling is abraded and generates friction heat in the shooting process, the energy is lost to reduce the speed of the gun when the gun is popped out of the chamber, the gun is difficult to maintain, and the service life of the gun barrel is shortened; the addition of a tail fin to the projectile, an undercut to the projectile tail, and a bottom exhaust to the projectile all provide improvements, but also add complexity and cost to the manufacture of the projectile. Thus, improvements in projectile technology are still needed.

Disclosure of Invention

The present invention provides a new artillery shell technology, a method for making the artillery shell rotate when the artillery shell is shot in a bore. The rotating projectile may enhance ballistic stability and increase the accuracy of the projectile firing.

The invention is technically characterized in that evenly distributed gas channels are added on the shell body of the shell, the gas channel grooves on the shell body and a barrel form gas injection channels (such as models shown in figures 1, 4 and 5), or the shell forms the gas injection channels independently (such as models shown in figures 6 and 7). The shell is pushed to rotate by the counterforce generated by the gas sprayed through the spraying channel. The invention is suitable for the gun barrel with smooth inner wall.

The uniformly distributed gas injection channels are used for uniformly stressing the shell and promoting ballistic stability, so that the number of the channels is more than two. The size and number of the gas channels are set according to the specification of the cannonball, the thrust of the cannonball needs to be considered, and the rotary thrust generated by injecting gas through the cannonball gas channels also needs to be considered. When the cannon is started, explosive gas in the cannon barrel expands, and part of the explosive gas deflects after passing through the gas injection channel, advances along the channel and is laterally ejected out of the front surface of the cannonball. This gas injection process produces rotational torque which in turn rotates the projectile. The gas injected into the front of the shell through the shell gas channel has a certain obstruction to the advance of the shell, but the injected gas quantity is small, the expansion speed is higher than the moving speed of the bullet, and the obstruction influence is small.

In the whole process of firing, the propelling and the rotation of the cannonball are generated by the explosion of gunpowder, the acting force on the cannonball is changed, the density distribution of the cannonball is not uniform, and the rotating speed of the cannonball is difficult to calculate accurately. A simplified approximate calculation of the rotation speed of the projectile is as follows:

the projectile rotation speed estimation formula is as follows: n = V/(π × XR) revolutions/sec

N is the rotating speed (rotation/second), V is the gun ejecting chamber speed (meter/second), R is the radius (meter) of the shell, and X is the ratio of the advancing average thrust to the average rotating thrust in the gun barrel after the gunpowder is exploded. And pi is the circumferential ratio. The product of the average rotary thrust and the radius of the cannonball is the rotation moment.

The size of X is related to the size and number of gas injection channels, and the channel exit direction. When the amount of gunpowder is enough, the larger the channel is, the more the channel is, the closer the included angle between the direction of the channel nozzle and the shell shaft is to 90 degrees, and the larger the rotary thrust obtained by the shell is. The acting force of the injected gas on the bullet is F, and the included angle between F and the bullet axis is phi, so that the F acting force can be decomposed into F + cos phi which reversely hinders the bullet from advancing and F + sin phi which propels the bullet to rotate. Therefore, when the included angle between the F and the projectile axis is larger than 45 degrees (the screw pitch of the spiral line at the nozzle of the gas channel is smaller than 4 times of the radius of the projectile), larger rotary thrust and energy utilization rate can be achieved. The gas injection channels are arranged in consideration of stability of structural strength, and increase of the size and number of the channels is premised on structural stability. The increase of the rotary thrust force under the condition of the same amount of the fire explosive means the decrease of the advancing thrust force of the cannonball, so the ratio of the rotary thrust force to the advancing thrust force of the cannonball is not suitable to be too small. The thrust and the rotary thrust of the projectile decrease as the projectile advances and rotates, but the rotary thrust decreases faster and the ratio becomes larger. When the rotary thrust is far smaller than the advancing thrust, the change of the ratio of the advancing thrust to the rotary thrust obtained by the cannonball is small, and the accuracy of calculating the rotating speed of the cannonball is higher in the formula N = V/(pi X R).

Assuming a bullet ejection chamber velocity V of 1000m/s, a bullet radius R of 6mm, an average advancing thrust of 200 times the average rotational thrust, i.e. X of 200, the rotational speed N at which the gun is ejected is about 265 revolutions per second.

Drawings

Figure 1 is an isometric view of a projectile with helically grooved gas channels.

Figure 2 is a view of a projectile with helically grooved gas channels at the barrel muzzle.

Figure 3 is a frame line view of projectiles with helically grooved gas channels in a barrel.

Fig. 4 is an explanatory diagram of a cannonball with spiral groove gas channels, wherein the number 1 indicates a cannonball middle shaft, the number 2 indicates an included angle between a spiral line of the spiral groove channels and a middle shaft, and the number 3 indicates the spiral groove gas channels.

Figure 5 is a schematic view of a projectile with helically grooved channels and linearly grooved gas channels.

Figure 6 is a bottom isometric view of a shell pattern with gas injection channels concealed within the shell.

Figure 7 is a top isometric view of a shell pattern with gas injection channels concealed within the shell.

Detailed description of the invention

Referring to fig. 4, the shell model is a bullet model, the number of spiral groove gas channels is 4, the groove depth is 0.2mm, the width is 1 mm, the included angle between the spiral line of the gas channel jet orifice and the bullet axis is 60 degrees, and the bullet radius is 6mm. The total area of the spiral groove channel cut is about 0.81 square millimeter, and the projection area of the bullet warhead bottom is S = pi R ² And =36 pi square mm. After the gunpowder in the barrel explodes, the ratio of the advancing thrust to the rotating thrust of the initial stage of the cannonball is equal to the ratio of the effective acting force area:

（36π-0.81-0.81cos(60°）/（0.81sin(60°））≈159

the thrust and the rotary thrust of the projectile decrease as the projectile advances and rotates, but the rotary thrust decreases faster and the ratio becomes larger. It is obvious that the projectile will eventually obtain a certain speed and rotation speed.

The specific rotating speed and the discharge speed of the bullet are determined according to the amount of the propellant, the length of a gun barrel and the like. Assume a designed bullet discharge velocity of 1000 m/s. The average ratio of the average propulsive force to the average rotational propulsive force is 200 and the bullet rotational speed is expected to be around 265 revolutions per second.

Claims

1. A method of rotating a projectile is characterized in that part of the gas explosively generated by the gunpowder is injected through gas injection channels in the shell body of the projectile, the reaction force of the injection causing the projectile to rotate.

2. The gas injection passage of claim 1 wherein the number of gas injection passages is greater than two.

3. The gas injection passage of claim 1 wherein the plurality of gas injection passages are uniformly distributed throughout the body of the bullet.

4. A gas injection passage as claimed in claim 1 wherein the helix of the gas injection passage port adjacent the nose of the bullet makes an angle of greater than 45 degrees with the axis of the bullet, i.e. the pitch of the helix is less than 4 shell radii.