Ventilated supercavitating projectile suitable for underwater launching

Abstract

The application discloses a ventilated super-cavitation projectile suitable for underwater launching, which comprises a tail, a sealing diaphragm, a blunt charge column and a bullet head. The tail is provided with a stepped center jet hole. The bullet head is provided with a flat head structure, and a center gas production chamber is arranged at the bottom of the bullet head. The blunt charge column is arranged in the center gas production chamber, and 4-12 equidistantly distributed radial jet holes are arranged at the tail end of the center gas production chamber. The bullet head and the tail are connected through threads, and the sealing diaphragm is arranged at the connection position. The ventilated super-cavitation projectile can meet the requirements of underwater gas curtain type low-resistance high initial velocity launching, and can also realize ventilation and drag reduction during the underwater navigation of the projectile, so that the initial velocity and the range of the projectile are improved.

Description

Technical Field

[0001] This invention relates to the field of drag reduction technology for high-speed underwater projectiles, specifically, to a ventilated supercavitating projectile suitable for underwater launch. Background Technology

[0002] With the development of underwater low-drag launch technology and ventilated supercavitation drag reduction technology, higher requirements have been placed on the design of ventilated supercavitating projectiles. That is, the projectiles should be suitable for underwater low-drag launch and be able to undergo ventilated supercavitation drag reduction after their speed decreases significantly after traveling a certain distance in the water, so as to achieve underwater low-drag high initial velocity launch and long-distance underwater navigation.

[0003] Currently, there are two main design approaches for underwater projectiles. One is the air curtain projectile, which uses internal channels and structural design to guide the exhaust gas from the rear of the projectile to the front, displacing the water column and reducing launch drag, thus achieving low-drag, high-velocity underwater launch. However, it cannot reduce drag while navigating underwater. The other is the ventilated supercavitating projectile, which can vent air to the side of the projectile while navigating underwater, helping to form a supercavitation bubble and reducing the projectile's drag. However, it lacks an internal jet structure and cannot be directly used for low-drag, high-velocity underwater launch. Neither of these two types of projectiles can simultaneously achieve high-velocity launch and low-drag navigation underwater, severely limiting the range and power of underwater projectiles. Summary of the Invention

[0004] The purpose of this invention is to provide a ventilated supercavitating projectile suitable for underwater launch. It can be launched at high initial velocity using an underwater air-mold low-drag launch method, and can continuously reduce drag by forming a ventilated supercavitation in the water, thereby achieving high initial velocity launch and long-distance navigation of underwater projectiles.

[0005] The technical solution to achieve the purpose of this invention is: a ventilated supercavitating projectile suitable for underwater launch, comprising a tail, a sealing diaphragm, an insensitive propellant grain, and a warhead;

[0006] The tail of the projectile is cylindrical in shape and has a stepped central nozzle and a threaded hole inside. From left to right, there are a primary nozzle, a secondary nozzle and a threaded hole, with the diameter increasing from small to large. The primary nozzle and the secondary nozzle together form the stepped central nozzle.

[0007] The projectile is divided into a threaded section, a cylindrical section and a frustum section from left to right. A gas-generating chamber is opened in the center of the threaded section and the cylindrical section, and a blunt-sensing propellant is placed in the gas-generating chamber. 4-12 radially distributed nozzles are opened at the right end of the gas-generating chamber. The nozzles are located on the cylindrical section downstream of the corner of the frustum section, 5-10 mm away from the sharp corner.

[0008] The tail and the head of the projectile are connected by threads, so that the stepped central nozzle and the gas generation chamber can be connected when the sealing diaphragm is broken.

[0009] The sealing diaphragm is fixed on the contact surface between the tail and the head of the projectile.

[0010] The diameter of the warhead is 1-2 mm smaller than that of the tail. The warhead gas generation chamber, radial nozzles, and the stepped central nozzle at the tail form a jet channel through which gas is ejected from the rear to the front of the warhead.

[0011] The insensitive drug column is tubular, with an insensitive layer coated on the inner hole and a base drug layer on the outer side. The insensitive drug column is fixed to the inner wall of the gas-generating chamber.

[0012] The sealing diaphragm is made of metal.

[0013] The gas generation and exhaust of the insensitive propellant column meet the following conditions:

[0014] During launch, the high-temperature and high-pressure gas in the space behind the missile breaks through the sealing diaphragm and is sprayed to the front of the missile through the stepped central nozzle at the tail and the gas generation chamber and radial nozzle of the warhead, reducing the launch resistance and igniting the blunt-sensing layer of the insensitive propellant.

[0015] After the projectile is fired at high speed into the water from the muzzle, a small amount of gas generated by the insensitive layer is ejected from the stepped central nozzle, increasing the pressure at the base of the projectile and reducing the pressure drag of the projectile during its flight. After traveling a certain distance, the speed of the projectile decreases significantly. At this time, the insensitive layer of the insensitive propellant burns out, and the base propellant layer of the propellant begins to burn, rapidly generating a large amount of propellant gas, which is ejected from the radial nozzle and the secondary nozzle.

[0016] Compared with the prior art, the present invention has the following significant advantages: (1) The ventilated supercavitating projectile for underwater launch provided by the present invention can form an air curtain to displace the water column in front of the projectile during the firing stage, which greatly reduces the firing resistance and increases the initial velocity. (2) During the high-speed navigation stage in water, the insensitive layer gas increases the pressure at the bottom of the projectile and reduces the pressure drag of the projectile. After the projectile's velocity decays, the insensitive propellant base layer burns rapidly to generate a large amount of gas, and the ventilation maintains the supercavitating shape of the projectile, thereby improving the projectile's velocity retention capability and range. (3) The ventilated supercavitating projectile for underwater launch provided by the present invention has a simple structure and can achieve low-drag movement inside and outside the barrel without complex mechanical actions. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a ventilated supercavitating projectile suitable for underwater launch according to the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of an insensitive drug cartridge.

[0019] Figure 3 This is a schematic diagram of the warhead structure. Detailed Implementation

[0020] This invention provides a ventilated supercavitating projectile suitable for underwater launch, comprising a tail section 1, a sealing diaphragm 2, an insensitive propellant grain 3, and a projectile head 4. The tail section is cylindrical, with a series of primary nozzles, secondary nozzles, and threaded holes arranged from left to right, increasing in diameter. The projectile head consists of a threaded section, a cylindrical section, and a frustum section from left to right. A gas-generating chamber is located at the center of the threaded and cylindrical sections, housing the insensitive propellant grain. Four to twelve equidistant radial nozzles are located at the right end of the gas-generating chamber, positioned 5-10 mm downstream of the corner of the frustum section on the cylindrical section. The projectile head and tail section are connected by threads, with a sealing diaphragm at the connection point. The gas generation and venting of the insensitive propellant grain satisfy the following conditions:

[0021] During launch, the high-temperature, high-pressure gas behind the missile breaks through the sealing diaphragm and ignites the blunt-sensing layer of the propellant.

[0022] When the projectile travels at high speed in water, the insensitive layer gas increases the pressure at the bottom of the projectile and reduces the pressure drag of the projectile. The projectile's velocity decreases significantly, and the insensitive propellant base layer burns rapidly to generate a large amount of gas, which is ejected from the radial nozzle and secondary nozzle to form a ventilated supercavitation, greatly reducing the resistance to navigation.

[0023] Furthermore, the diameter of the warhead is slightly smaller than that of the tail. The warhead's gas-generating chamber, radial nozzles, and the stepped central nozzle at the tail form a jet channel from the rear of the warhead to the front of the warhead.

[0024] Furthermore, the number of radial nozzles is 4-12, and the nozzles are located on the cylindrical section of the projectile, 5-10 mm away from the sharp edge of the projectile.

[0025] Furthermore, the insensitive propellant is fixed to the inner wall of the gas-producing chamber and burns in layers starting from the inner hole.

[0026] Furthermore, the sealing diaphragm is made of metal and is fixed to the contact surface between the tail and the head of the projectile.

[0027] The present invention will now be further described with reference to the accompanying drawings.

[0028] The present invention provides a ventilated supercavitating projectile suitable for underwater launch, comprising a tail, a sealing diaphragm, a blunt-sensitive propellant grain, and a warhead.

[0029] like Figure 1During launch, the propellant gases from the rear of the projectile act on a sealing diaphragm through the stepped central nozzle at the tail. When the pressure inside the secondary nozzle exceeds the diaphragm rupture pressure, the sealing diaphragm breaks open, and the rear propellant gases are ejected into the projectile's forward tube through the stepped central nozzle, the gas-generating chamber, and the radial nozzles, displacing the water column inside the tube and significantly reducing launch drag. Simultaneously, the propellant gases ignite the insensitive layer of the propellant grain. After the projectile exits the muzzle at high speed and enters the water, it forms a natural supercavitation. At this time, the gases from the insensitive layer of the propellant grain are ejected rearward from the stepped central nozzle, increasing the pressure at the bottom of the projectile and reducing pressure drag. As the projectile's velocity decays, the cavitation shrinks and no longer covers the entire projectile, significantly increasing flight drag. At this point, the base layer of the insensitive propellant grain burns rapidly, generating propellant gases that are ejected from the radial nozzles and the stepped central nozzle. These gases, under the influence of the incoming flow, combine with the localized cavitation in the projectile to form a supercavitation that envelops the entire projectile, preventing an increase in flight drag and effectively improving the projectile's velocity retention and range.

Claims

1. A ventilated supercavitating projectile suitable for underwater launch, characterized in that: It includes the tail (1), sealing diaphragm (2), insensitive propellant (3) and projectile (4); The projectile tail (1) is cylindrical in shape and has a stepped central nozzle and a threaded hole inside. The nozzle is a first-level nozzle, a second-level nozzle and a threaded hole, with the diameter increasing from small to large. The first-level nozzle and the second-level nozzle form a stepped central nozzle. The projectile (4) is divided into a threaded section, a cylindrical section and a frustum section in sequence. A gas-generating chamber (4-1) is opened in the center of the threaded section and the cylindrical section. The gas-generating chamber (4-1) contains a blunt-sensitive propellant (3). The tail (1) and the head (4) are connected by threads, so that the stepped central nozzle and the gas generation chamber (4-1) can be connected when the sealing diaphragm (2) is broken; The sealing diaphragm (2) is fixed on the contact surface between the tail (1) and the head (4); The gas generation and exhaust of the insensitive propellant (3) meet the following conditions: During the firing process, the high temperature and high pressure gas in the space behind the projectile breaks through the sealing diaphragm (2) and is sprayed to the front of the projectile through the stepped central nozzle of the tail (1) and the gas generation chamber (4-1) and radial nozzle (4-2) of the projectile (4), reducing the firing resistance and igniting the insensitive layer of the insensitive propellant (3); After the projectile is fired into the water at high speed from the muzzle, a small amount of gas generated by the insensitive layer is sprayed out from the stepped central nozzle, increasing the pressure at the bottom of the projectile and reducing the pressure difference drag of the projectile during travel; After traveling a certain distance, the speed of the projectile decreases significantly. At this time, the insensitive layer of the insensitive propellant (3) burns out, and the base propellant layer of the propellant begins to burn, rapidly generating a large amount of gunpowder gas, which is sprayed out from the radial nozzle (4-2) and the secondary nozzle.

2. The ventilated supercavitating projectile suitable for underwater launch according to claim 1, characterized in that: The gas-generating chamber (4-1) has 4-12 equidistant radial nozzles (4-2) at its right end. The nozzles are located on the cylindrical section downstream of the corner of the frustum section, 5-10 mm from the sharp corner.

3. The ventilated supercavitating projectile suitable for underwater launch according to claim 1, characterized in that: The diameter of the warhead (4) is 1-2 mm smaller than that of the tail (1). The warhead gas chamber (4-1), the radial nozzle (4-2), and the stepped central nozzle of the tail (1) form a jet channel from the rear of the warhead to the front of the warhead.

4. The ventilated supercavitating projectile suitable for underwater launch according to claim 1, characterized in that: The insensitive drug column (3) is tubular, with an insensitive layer (3-1) coated on the inner hole of the drug column and a base drug layer (3-2) on the outer side. The insensitive drug column (3) is fixed to the inner wall of the gas production chamber (4-1).

5. The ventilated supercavitating projectile suitable for underwater launch according to claim 1, characterized in that: The sealing diaphragm (2) is made of metal.

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