Shape optimization of the cavitator for a supercavitating torpedo. First developed into a workable design for the soviet navy during the cold war, the concept of supercavitating torpedoes has fascinated military engineers ever since, although little practical headway seems to have been achieved subsequently, aside from a number of stalled projects and aborted attempts. Mathematical theory and numerical simulation of bubbly cavitating nozzle flows. A supercavity can be maintained in one of two ways. Supercavitating torpedo offers speed of 230 miles per hour. The basic similarity parameters of the supercavitation flows are cavitation number and reynolds number, which are defined as. Iran tests supercavitating torpedo pakistan defence.
A specific configuration of torpedo is obtained for required speed and supercavitation and the details of process are discussed thoroughly. Research progress of supercavitation hydrodynamics. Supercavitation is a hydrodynamic process in which an undersea body is almost entirely enveloped in a layer of gas initiated at a cavitator mounted at the forward end. Hydrodynamic performance of 2d shock free supercavitating hydrofoils with a spoiler on the. An experimental investigation of artificial supercavitation with variation of the body shape 1byoungkwon ahn. Us navy is developing supersonic submarine that could. Supercavitation seminar report, ppt, pdf for mechanical. In order to encompass all possible cases, we propose the following definition. The problems include the generation,development and stability of supercavitation,hydrodynamic forces acting on the supercavitating vehicle,and the hydroballistics of vehicle. Control methods for highspeed supercavitating vehicles. Drag reduction of a rapid vehicle in supercavitating flow. Supercavitation advances and perspectives a collection dedicated to the 70th jubilee of yu.
It is visible that the model jet works in vapor cavity with boundaries closing on the watervapor jet flowing out from the nozzle. A supercavitating torpedo is a torpedo using the effect of supercavitation to create a bubble around the torpedo to move at high velocity under water. The cavity the bubble reduces the drag on the object and this makes supercavitation an attractive technology. To complement these analytical efforts, a sophisticated experimental program has. Some sources have speculated it is based on the russian va111 shkval supercavitation torpedo, which travels at the same speed 4 5 6.
Controlled supercavitation formed by a ring type wing. The following is a list of supercavitating torpedoes which have been developed or are in development. Supercavitation as the effective tool for water drag reduction. Bubbleenclosed submarines could go really, really fast. Barracuda was meant to be launched from submarines and surface vessels, and test models could travel straight and curved paths. But what if it were possible to enclose a submarine in a gas as it travels through liquid. Zhukovskyroshko solves the closure problem by satisfying the dynamic free surface condition. Supercavitation is the state of the art technology that may revolutionize underwater propulsion systems cavitation cavitation is the process of formation of vapour bubbles of flowing fluid in a region where the pressure of the liquid falls below its vapour pressure and the sudden collapsing of these vapour bubbles in region of high pressure. Supercavitation could let submarines move ridiculously fast. Shortly afterwards, its liquidfuel rocket ignites and propels it to speeds of up to 200 knots 370 kmh. Supercavitation is the use of a cavitation bubble to reduce skin friction drag on a submerged object and enable high speeds. And the drag force acting on this supercavitating torpedo dictates the thrust.
Ventilated supercavitation is a promising technique to achieve highspeed transport underwater by generating a gas bubble enclosing a moving object through ventilation. Watertunnel tests have already proven that speed can be. Natural supercavitation characteristic simulation of small. The torpedo 62 has a launch weight of 1,450kg and can carry high explosive warhead. Some sources have speculated it is based on the russian va111 shkval supercavitation torpedo, which travels at the same speed. Iran claimed to have successfully tested its first supercavitation torpedo, the hoot whale, on 23 april 2006. Va111 shkval pictures va111 shkval underwater rocket in 1995 it was revealed that russia had developed an exceptionally highspeed unguided underwater missile which has no equivalent in the west. The basic concept of supercavitation weapon and its application are introduced. Explore supercavitation with free download of seminar report and ppt in pdf and doc format. A torpedo test vehicle utilizing a ventilated supercavitating propeller was the subject of an experimental program carried out on the underwater cableway facility at morris dam. Theory, experiment and scale effects v v serebryakov 1, r e a arndt 2, and j e dzielski 3 1 institute of hydromechanics of nas, 84 zhelyabov str. It can only barely maneuver, goes more or less in a straight line and. A robust impulsive control strategy of supercavitating vehicles in.
Among those, one of the most strong factors is effect of a free. For several years, the united states navy has supported basic research and development involving supercavitating highspeed bodies. Optimum design of a supercavitating torpedo considering overall size, shape, and structural con. A supercavitating torpedo is a complex high speed undersea weapon that is. Applications include torpedoes and propellers, but in theory, the technique. Then the cavitation number influence on cavitation form is concerned and contrast with the empirical formula of cavitation form. Uses the supercavitating propeller is being used for military purposes and for high performance boat racing 3 vessels as well as model boat racing 4. A supercavitating torpedo is a complex system that experiences extreme operating conditions. According to the flow configuration shape and relative motion of the walls limiting the flow field, or physical properties of the liquid, it can take various figures. The name supercavitating torpedo is derived from the cavity of water vapor that is generated at the nose of the torpedo or cavitator 1 and engulfs the complete structure.
However, implementing this technique requires clear understanding and precise control of supercavity behaviors under unsteady conditions in practical applications. Under this program, the theory of highmachnumber underwater flows has been investigated and firstprinciples modeling of cavity development and body dynamics have been addressed. In view of assumption 6, that the body is not spinning about its symmetry axis. The trick with maintaining supercavitation is keeping the torpedo enclosed in the gas bubble. The design is used in military applications, highperformance racing boats, and model racing boats. Supercavitation is the use of cavitation effects to create a large bubble of gas inside a liquid, allowing an object to travel at great speed through the liquid by being wholly enveloped by the bubble. Pdf design and development of a supercavitating torpedo body. A soviet supercavitation torpedo called shakval was able to reach a speed of 370kmh or more much faster than any other conventional torpedoes.
Militarygfys is a place for sharing military moments from around the world and throughout history in the small, easy to share. The hoot torpedo is still in the testing phase, the officials report, but once it is fully operational it should be able to travel about 12,000 yards approximately six nautical miles at a speed of about 200 knots per hour. Three senior defense officials report that iran testfired a highspeed torpedo near the strait of hormuz on sunday. This makes turning maneuvers tricky, as a change of heading will force a portion of the torpedo outside the bubble, causing sudden drag at 230 miles an hour. Materials and methods in the present study, the cavitating flow is assumed to be the homogeneous mixture of isentropic liquid and vapour which remain in kinematic and thermodynamic equilibrium, that is, liquid and vapour. The main hydrodynamic problems related with supercavitation weapon design and the research progress are also presented. The torpedo controls its direction using four fins that skim the inner surface of the supercavitation.
Artificial supercavitation is a promising technology for the drag reduction of highspeed underwater vehicles, whereby a cavity is generated through air entrainment to encompass the entire vehicle. Supercavitation projectile can achieve to intercept torpedoes, damage ships and. Developed in the 1970s, shkval is equipped with a bubble generator in the nose that envelops the torpedo in a gas membrane while a solid rocket fuel engine provides thrust. Iran claimed to have successfully tested its first supercavitation torpedo on 2 april and 3 april 2006. Torpedo 2000 from saab is a dualpurpose heavy weight torpedo system in use with the submarine fleet of the royal swedish navy. Exaggerated diagram of supercavitation formation around a torpedo body. Department of free boundary flows national academy of sciences of ukraine kyiv ukraine. Force analysis of underwater object with supercavitation. In this approach, the water near the tip of the projectile or torpedo literally vaporizes from the high speed, producing a pocket in which to fly the weapon underwater. The chinese navy and us navy are reportedly working on their own supercavitating submarines using technical information obtained on the russian va111 shkval supercavitation torpedo a supercavitating propeller uses supercavitation to reduce water skin friction and increase propeller speed. This cavity separates the torpedo hull from the water, thereby eliminating much of the viscous drag. Design and development of a supercavitating torpedo body. The torpedo model is then constrained from rigid body translation but free to expand and contract due to the applied pressure forces. Experimental investigation of ventilated supercavitation.
It can be effectively launched against all types of submarines and surface ships. Hydrodynamics of supercavitating bodies at an angle of. Using supercavitation techniques, the torpedo becomes an underwater missile, capable of reaching its target before the threat can respond. Optimum design of a supercavitating torpedo considering. Also explore the seminar topics paper on supercavitation with abstract or synopsis, documentation on advantages and disadvantages, base paper presentation slides for ieee final year mechanical engineering me or production automobile students for the year 2019 2020. Among those, one of the most strong factors is effect of a free border and, especially, gravity effect, which is caused.
The disadvantages are that although it can go at high speeds, its range is limited to a few km, its very noisy and immediately gives away the location of whatever launched it. Iran has claimed to have successfully tested its first supercavitation torpedo on 2 april and 3 april 2006. Impact dynamics of a supercavitating underwater projectile. Introduction a supercavitating torpedo is a complex system that experiences extreme operating conditions.
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