108 results about "Supercavitation" patented technology

A device for mixing the components of a mass flow flowing through it, provides a particularly homogeneous mixture with any desired long-term stability, even if components which are generally immiscible or can only be mixed with very great difficulty are being mixed. The device has a body (8), which it is difficult for medium to flow around, arranged in a through-flow chamber (4), this body being arranged at least partially in a part of the through-flow chamber (4) which widens in the direction of flow, so that the cavitation action and mixing action of the supercavitation field generated by the body (8) which it is difficult for medium to flow around is significantly reinforced.

Utilisation of geothermal energy in depths above 5 km could contribute considerably to resolving the global problems related to a lack of energy and to glasshouse gases from fossil fuels. The invention describes innovative equipment which makes deep holes in geological formations (rock) by disintegrating the soil into blocks carried to the land surface through the excavated hole filled with liquid, using transport modules yielded up by gas buoyancy interaction in the transport module utilising supercavitation. In an opposite direction—by help of negative buoyancy—the necessary energy carriers, materials and components, or entire devices required for rock excavation, are carried to the bottom. The opportunity to transport rock in entire blocks reduces energy consumption considerably, because the rock is disintegrated in the section volumes only. Some of the extracted rock and material carried from the surface is used to make a casing of the hole using a part of the equipment. The equipment also allows the generation of the necessary high pressure of liquid at the bottom of the hole, to increase permeability of adjacent rock. The equipment as a whole allows by its function that there is almost linear dependence between the price and depth (length) of the produced hole (borehole).

The invention discloses a numerical simulation method for cavitation compressible flow shock wave dynamics and belongs to the field of numerical simulation of cavitation compressible flow and shock wave dynamics. A three-dimensional computing watershed based on three-dimensional geometric modeling software is established; a three-dimensional computing watershed mesh is divided based on mesh generation software; a cavitation compressible flow computational fluid dynamics model is established; an initial boundary condition is set to perform a three-dimensional computational domain flow field numerical computation; based on flow field post-processing software, the computational result is post-processed to obtain the unsteady evolution process of a multi-phase bubble structure. The numerical simulation method for cavitation compressible flow shock wave dynamics in the invention facilitates in-depth study of the cavitation physical mechanism, can be applied to the field of cavitation compressible flow and shock dynamics numerical simulation and solves related engineering problems. The cavitation compressible flow and shock dynamics numerical simulation engineering application area comprises hydraulic machinery, marine propellers, aviation turbo pump induction wheels, underwater supercavitation weapon applications.

A piecewise linear method for analyzing supercavitation navigation body kinetic characteristics includes the steps that step1, a supercavitation navigation body kinetic model is built; step2, piecewise linear fitting is performed on a non-linear sliding force function in the supercavitation navigation body kinetic model to obtain a linear sliding force function; step3, parameters of the supercavitation kinetic model are set; step4, the supercavitation kinetic model with the piecewise linear sliding force Fp function is adopted for obtaining a sole balance point of a supercavitation navigation body, linearization is performed on a system at the balance point to obtain a jacobian matrix of the system and a characteristic equation at the balance point, characteristic values of the system are obtained, and the balance point of the system is judged to be an unstable saddle focus. By the adoption of the piecewise linearization of the sliding force function, the supercavitation navigation body kinetic model is simplified, so that the balance point position and stability conditions of the model have concise analytical expressions, and the supercavitation navigation body kinetic characteristics are analyzed more conveniently.

The invention discloses a supercavitation torpedo. The torpedo is provided with a gas turbine engine, a helm gear driven and controlled by an electric motor, gas nozzles evenly formed in the inner circumferential direction of the bowl wall of a ventilation bowl and other devices, by using a gas turbine motor as power, high-speed motion and over-distance travel of a heavy thermal torpedo can be achieved, and a wide range of speed changing or deepening of the torpedo can be achieved. According to the supercavitation torpedo, a tail gas gathering cabin is arranged in a front cabin, tail gas generated by the engine gathers in the tail gas gathering cabin and is discharged through the ventilation bowl at the front end, the gas nozzles evenly formed in the ventilation bowl, supercavitation formed on the outer side of the supercavitation torpedo is surrounded by gas more evenly and stably, the supercavitation formed on the outer side of the supercavitation torpedo is more even and stable, thus forward resistance of the torpedo is greatly reduced, and the forward speed and range of the torpedo are increased.

The invention discloses a projectile holder separating system based on the momentum theorem and relates to projectile holder separating systems. When an existing integral projectile holder is separated from a projectile by means of air resistance or a muzzle check ring, a long flying distance is needed for separating the projectile holder from a projectile body, and the track of the projectile body is seriously affected by the projectile holder; meanwhile, due to the fact that the projectile holder enters water at the same time along with the projectile body, the water surface splashing shape and the cavitation shape which are formed after the projectile enters water are directly disturbed; in addition, the shooting quality of the image showing the process that the projectile enters water by an operator is reduced due to the disturbance of the projectile holder, and consequentially data provided by the image are not accurate. According to the projectile holder separating system based on the momentum theorem, a buffer spacer is arranged between an accelerating projectile holder body and a blocking projectile holder body and tightly attached to the blocking projectile holder body, and the accelerating projectile holder body is a rotating body; a projectile storage cavity is formed in the accelerating projectile holder body; the projectile is placed in the projectile storage cavity, and the head of the projectile faces a muzzle; a projectile passing hole is machined in the blocking projectile holder body in the length direction of the blocking projectile holder body; a recovery cover is located outside a gun barrel and faces the muzzle of the gun barrel. The projectile holder separating system based on the momentum theorem is used for supercavitation projectile experiments.

The invention provides a self-adaptive fault-tolerant control method for a supercavitation navigation body. The self-adaptive fault-tolerant control method comprises the following steps: 1, designinga mathematical model of the supercavitation navigation body; 2, establishing a system uncertainty and actuating mechanism fault model through the mathematical model in the step 1; and 3, designing anadaptive control law through the model in the step 2. The self-adaptive fault-tolerant control method ensures the stability of the navigation body closed-loop control system in the presence of executing mechanism faults and uncertainty.

The invention relates to a supercavitation experimental device, in particular to a vehicle underwater launching experimental device for supercavitation mechanism research. The vehicle underwater launching experimental device for supercavitation mechanism research comprises a pneumatic launching system, a launching system supporting device, a water tank and an observation and recording system, wherein the launching system supporting device is placed on one side of the water tank provided with an electric knife gate valve; the pneumatic launching system is fixedly arranged on the launching system supporting device; and the observation and recording system is placed on one side of the water tank provided with an acrylic plate. The vehicle underwater launching experimental device for supercavitation mechanism research can truly reflect the supercavitation phenomenon, and further changes the launching speed of the vehicle by changing the air pressure set value of the high-pressure air cylinder of the pneumatic launching system, thereby realizing the supercavitation mechanism research of vehicles with different speeds; by replacing pipe valve connectors and launching tubes with differentinner diameters of the pneumatic launching system, the vehicles with different sizes can be launched, and the supercavitation mechanism research of the vehicles with different sizes can be realized;and by replacing the vehicles with different shapes of the pneumatic launching system, the supercavitation mechanism research of the vehicles with different shapes is realized.

The invention discloses an empennage stable high-speed supercavitation projectile. A projectile body comprises a head cavitation device, a shoulder frustum transition section, a rear cylinder and a tail empennage. The empennage stable high-speed supercavitation projectile adopts a supercavitation drag reduction principle, the resistance at the underwater high-speed supercavitation movement stage is reduced by 80% or above compared with the resistance of an ordinary projectile not adopting the supercavitation drag reduction technology, under the same initial launching speed condition, the rangeof the empennage stable high-speed supercavitation projectile is greatly increased compared with the range of the ordinary projectile, and the speed storage performance of the projectile is relatively excellent. Due to the fact that the projectile is additionally provided with the empennage, the trajectory stability of the underwater high-speed supercavitation projectile is remarkably improved, the problems that the trajectory of the ordinary projectile is prone to bending and is poor in linearity are solved, and the linearity and the predictability of the trajectory are greatly improved.

The invention provides a supercavitation underwater vehicle. The supercavitation underwater vehicle comprises a vehicle body and annular skirt sections; the vehicle body comprises a front-section conical part and a cylindrical part; a plurality of annular grooves are formed in part of the surface of the front-section conical part, the annular skirt sections are installed on the outer surface on the tail portion of the cylindrical part of the vehicle body, a plurality of annular air bags which are not communicated with each other are arranged in the annular skirt sections, and air supply holesare formed in the portions, outside of the tail portion of the cylindrical part of the vehicle body, in the air bags, and used for being communicated with the air bags and a cavity in the vehicle body; when the air bags are not inflated, the annular skirt sections do not protrude out of the outer surface of the cylindrical part of the vehicle body. According to the supercavitation underwater vehicle, by improving the structural design of the vehicle body, it can be effectively achieved that the supercavitation formed in the front section of the vehicle body is stabilized, the running resistance of the vehicle body is reduced, the noise is reduced, and the velocity of the underwater vehicle is increased.

The invention discloses an anti-submarine missile based on a dive buffer device and a control method. A generation principle of supercavitation is bidirectionally applied, a propelling device at the tail pushes a missile body to reach a cavitation speed, a cavitator at the head sprays reverse jet flow, and the water surface is cavitated in advance before the missile body arrives, so that it is guaranteed that the missile body is located in a complete and stable supercavity in the whole dive process, direct slamming with water is avoided, and an effective buffering effect is provided for the whole missile body structure; due to the fact that the missile body reaches the cavitation speed before entering water, compared with the reverse jet flow jetted by the head cavitator, the purpose of head cavitation can be achieved without jetting the jet flow at a too high speed, namely, the cavitator does not need large energy; and a thermoelectric conversion module is applied, the problem that a power device is overheated is solved, redundant useless energy of the power device can be stored and reused, and the energy cost is greatly reduced.

A method and apparatus are disclosed for inducing a supercavitating flow inside a fuel injection nozzle orifice to reduce the penetration length of the fuel spray, maintain high levels of fuel atomization, and improve uniformity of the fuel spray exiting the nozzle such that high-pressure injectors can be used on small engines. This reduction in penetration length is accomplished without any reduction in upstream fuel pressure.

The invention discloses a charge-type cavitation generating structure for a supercavitation underwater vehicle. The interior hollow of the mid-rear section of the vehicle is used as the combustion chamber. The propellant is filled with the interior space along the inner wall of the combustion chamber, but a cylindrical cavity is left along the projectile axis. The front part of the combustion chamber is connected with the leading air duct, and the diameter of the leading air duct is slightly smaller than that of the propellant cavity. A lead air duct extends to that bullet head portion and isconnected with the nose vent hole and communicates with the external environment. A tail part of that combustion chamber is connected with a tail nozzle, and the tail nozzle communicates with the external environment in the form of a funnel. The scheme of the invention utilizes a large amount of gas and thrust generated during the combustion process of the propellant to generate cavitation, and prolongs the maintenance time of the supercavitation state of the high-speed underwater vehicle while continuously providing thrust.

The invention relates to an aircraft active load reduction structure based on a cavitator. A gas injection flow channel is designed in the head of an aircraft, and gas flow injection holes are designed in the outer side face of the aircraft. A cavitator is designed at the top end of the head of the aircraft, the cavitator is of a disc-shaped structure with an acute angle edge, and ventilation is conducted through airflow jet holes behind the acute angle structure to form supercavitation bubbles surrounding an object. A gas injection on-off valve is located behind the interior of the head of the aircraft, is connected with an injection flow channel and a high-pressure gas bottle and is directly controlled by an aircraft gas injection control system to control on-off of air flow. And the high-pressure gas cylinder is positioned at the rear part of the gas injection on-off valve and stores all high-pressure gas required for generating the supercavity. High-pressure compressed air serves as a ga source, and compared with fuel gas injection load reduction, the system is more compact and smaller and is more suitable for being applied to small and medium-sized underwater vehicles.

The invention discloses an air and water stamping combined cross-medium anti-ship and anti-submarine missile. An liquid oxidizing agent carried by the missile enters a combustion chamber to be subjected to primary combustion with solid metal fuel, gas enters an afterburning chamber through a spraying pipe to be converged with air sucked from the head of a missile body, oxygen in the air and a large amount of fuel-rich gas in the fuel gas are subjected to secondary afterburning and then are ejected out from a tail large spray pipe in an accelerated expansion manner; and the missile close to an enemy throws away from missile wings, opens a fuel gas outlet cover plate at the head and enters water, meanwhile, the fuel gas guided to the head from a combustion chamber is sprayed out from an outlet to the periphery, the fuel gas and the opened cover plate together assist the missile sailing at a high speed to form a stable supercavitation on the periphery of the missile body, water flows in from a tip in front of a fuel gas outlet and located outside a supercavitation area and is led to the combustion chamber for reacting with metal fuel, and at the moment, an engine is in a water stamping working mode until a target is hit, a combat unit fuze is triggered, and damage strike is formed on the enemy.

The invention discloses a separable bow structure of a supercavitation underwater vehicle. The separable bow structure comprises a split type flow guide cover unit, a power-losing type electromagnet unit, a connecting rib ring and an underwater vehicle hull. The split type flow guide cover unit is composed of a flow guide cover upper portion, a flow guide cover lower portion and buoyancy foam, andthe buoyancy foam is fixed to an inner surface of the flow guide cover upper portion in a bonding mode. The power-losing electromagnet unit is composed of a ferromagnetic disc and a power-losing electromagnet. The ferromagnetic disc is fixed on an internal rib ring of the split type flow guide cover unit; the four ferromagnetic discs are evenly distributed in a circumferential direction, an included angle between the center of each ferromagnetic disc and a boundary between the upper portion of the flow guide cover and the lower portion of the flow guide cover is kept to be 45 degrees, circular grooves are evenly formed in the connecting rib ring in the circumferential direction, and power-losing type electromagnets are installed in the circular grooves; a connecting rib ring is in threaded connection with the underwater vehicle hull; and a power line channel is further formed in the circular grooves and used for connecting the power-losing type electromagnets with a power supply unitin the underwater vehicle hull through a power line.

The invention discloses a supercavitation projectile regarding surface controlling drag reduction. The supercavitation projectile regarding surface controlling drag reduction comprises a projectile body, buffers, a brace rod, a cavitation device, a sensor, a controller and a driver; the sensor for sensing the projectile speed is installed at the front end of the middle portion of the projectile body; the controller is installed in the projectile body, and receives information from the sensor and emits a control instruction; the driver is installed at the rear end of the projectile body and responds to the command of the controller to adjust the telescopic positions of the buffers; and the four buffers are uniformly distributed on the driver at the tail end of the projectile body. The supercavitation projectile can be kept stable in a gas cavity, and is simple in structure, easy to achieve and wider in intelligent application range.

The invention discloses a supercavitation navigation body LPV controller design method, which is used for solving the acceleration section control problem in the underwater navigation process of a supercavitation navigation body, and mainly comprises the following steps: firstly, establishing a cavitation form model based on an independent expansion principle, and deducing a tail sliding force and tail vane wetting rate model according to the cavitation form model, establishing a nonlinear mathematical model of a supercavitation navigation body, then assuming the model to obtain a navigation body longitudinal plane mathematical model, establishing a parameter dependent LPV model about the self speed and the tail vane wetting rate of the navigation body based on the longitudinal plane mathematical model, and finally designing an H infinite robust controller for each state vertex of the navigation body, and connecting controller parameters in series by using a robust variable gain method, and establishing a global controller. According to the method, mathematical simulation is used for proving that the constructed controller can meet the control requirement, good robustness is achieved, and acceleration section depth-keeping control can be conducted on the navigation body under a certain interference effect.

The invention discloses a PIV tracer particle wall spreading device and belongs to the field of flow measurement in the near wall area. The device comprises a particle generator, a high pressure softpipe and a wall particle injection device, wherein the particle generator comprises an air inlet, a particle outlet and a stirrer, the particle outlet of the particle generator is connected with the wall particle injection device through the high pressure soft pipe, the wall particle injection device has a chamber, a particle injection hole and a thin cover plate, the chamber is provided with theparticle injection hole, the particle injection hole is provided with a pressure sensor at the downstream, and the thin cover plate is arranged above the chamber. The device is advantaged in that a problem that the existing PIV tracer particle spreading method cannot make PIV tracer particles enter the boundary layer or the supercavitation is solved, injection of the PIV tracer particles into thenear wall region is achieved, and the good technical support is provided for research of the supersonic or hypersonic boundary layer transition and ventilated supercavitation flow mechanism.

The invention relates to a supercavity image enhancement method, which comprises the following steps of: 1, carrying out graying processing on a supercavity color image to obtain a gray level distribution histogram of the supercavity image, and denoising the gray level image by utilizing a Gaussian smoothing median filtering method; 2, histogram equalization processing is carried out on the de-noised gray level distribution histogram in the step one; 3, judging whether the acquisition of the navigation body in the vacuoles on the edges of the vacuoles has interference or not, if the acquisition of the navigation body in the vacuoles has interference, corroding the interference in the vacuoles by using a morphological expansion corrosion algorithm, and if the acquisition of the navigation body in the vacuoles has no interference, executing step 4; 4, performing Roots algorithm edge detection on the processed image, and extracting the edge contour of the vacuoles; and 5, carrying out data fitting by utilizing the coordinate data extracted from the edge curve, finishing mathematical modeling of the supercavity edge, and obtaining parameter data of the cavity shape. According to the method, the cavitation interference caused by complex environmental factors can be eliminated, and the supercavitation shape can be accurately obtained.

A water-entry projectile capable of supercavitation and spin-stabilization comprises a forward section having one or more forward stepped sections, each stepped section being symmetrical in rotation about an axis and having a radius at an aft end that is different from a radius of a front end of an adjacent rearwardly located stepped section; an aft section having an aft stepped section, the aft stepped section being symmetrical in rotation about the axis and having a maximum radius larger than a maximum radius of the forward section; and wherein the aft section is located substantially aft of a center of gravity of the projectile.