Three senior defense officials report that iran testfired a highspeed torpedo near the strait of hormuz on sunday. Introduction a supercavitating torpedo is a complex system that experiences extreme operating conditions. 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. Control methods for highspeed supercavitating vehicles. Explore supercavitation with free download of seminar report and ppt in pdf and doc format.
Supercavitation seminar report, ppt, pdf for mechanical. The allure of supercavitating torpedoes naval technology. Optimum design of a supercavitating torpedo considering overall. Supercavitation advances and perspectives a collection dedicated to the 70th jubilee of yu. Supercavitation could let submarines move ridiculously fast. In 2004, german defense contractor diehlbgt announced the barracuda, a technology demonstrator torpedo meant to travel up to 194 knots. Torpedo 2000 from saab is a dualpurpose heavy weight torpedo system in use with the submarine fleet of the royal swedish navy. 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. Supercavitating torpedo offers speed of 230 miles per hour. A robust impulsive control strategy of supercavitating vehicles in. Department of free boundary flows national academy of sciences of ukraine kyiv ukraine. The torpedo 62 has a launch weight of 1,450kg and can carry high explosive warhead.
The basic concept of supercavitation weapon and its application are introduced. 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. Hydrodynamic performance of 2d shock free supercavitating hydrofoils with a spoiler on the trailing edge. 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. Impact dynamics of a supercavitating underwater projectile. 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. 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. Hydrodynamic performance of 2d shock free supercavitating hydrofoils with a spoiler on the. Controlled supercavitation formed by a ring type wing. Using supercavitation techniques, the torpedo becomes an underwater missile, capable of reaching its target before the threat can respond. Barracuda was meant to be launched from submarines and surface vessels, and test models could travel straight and curved paths.
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. 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. 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. Some sources have speculated it is based on the russian va111 shkval supercavitation torpedo, which travels at the same speed 4 5 6. 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. Hydrodynamics of supercavitating bodies at an angle of. The main hydrodynamic problems related with supercavitation weapon design and the research progress are also presented. A supercavity can be maintained in one of two ways. Force analysis of underwater object with supercavitation. Some sources have speculated it is based on the russian va111 shkval supercavitation torpedo, which travels at the same speed.
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. Natural supercavitation characteristic simulation of small. It can be effectively launched against all types of submarines and surface ships. Bubbleenclosed submarines could go really, really fast. The following is a list of supercavitating torpedoes which have been developed or are in development.
To complement these analytical efforts, a sophisticated experimental program has. For several years, the united states navy has supported basic research and development involving supercavitating highspeed bodies. A supercavitating torpedo is a complex high speed undersea weapon that is. An experimental investigation of artificial supercavitation with variation of the body shape 1byoungkwon ahn. 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. 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. Then the cavitation number influence on cavitation form is concerned and contrast with the empirical formula of cavitation form. Supercavitation projectile can achieve to intercept torpedoes, damage ships and. The trick with maintaining supercavitation is keeping the torpedo enclosed in the gas bubble. Applications include torpedoes and propellers, but in theory, the technique. Iran claimed to have successfully tested its first supercavitation torpedo on 2 april and 3 april 2006. Pdf supercavitaiton is the phenomenon of reducing the pressure of fluid especially water over the surface of a marine body to reduce drag and. Pdf design and development of a supercavitating torpedo body. Mathematical theory and numerical simulation of bubbly cavitating nozzle flows.
Zhukovskyroshko solves the closure problem by satisfying the dynamic free surface condition. Watertunnel tests have already proven that speed can be. 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. A supercavitating torpedo is a complex system that experiences extreme operating conditions. It is visible that the model jet works in vapor cavity with boundaries closing on the watervapor jet flowing out from the nozzle. Iran has claimed to have successfully tested its first supercavitation torpedo on 2 april and 3 april 2006. Iran claimed to have successfully tested its first supercavitation torpedo, the hoot whale, on 23 april 2006. In order to encompass all possible cases, we propose the following definition. The design is used in military applications, highperformance racing boats, and model racing boats. A soviet supercavitation torpedo called shakval was able to reach a speed of 370kmh or more much faster than any other conventional torpedoes. Shortly afterwards, its liquidfuel rocket ignites and propels it to speeds of up to 200 knots 370 kmh.
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. 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. Iran tests supercavitating torpedo pakistan defence. In view of assumption 6, that the body is not spinning about its symmetry axis. 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. And the drag force acting on this supercavitating torpedo dictates the thrust. Drag reduction of a rapid vehicle in supercavitating flow. Supercavitation as the effective tool for water drag reduction. The torpedo controls its direction using four fins that skim the inner surface of the supercavitation. Optimum design of a supercavitating torpedo considering overall size, shape, and structural con. It can only barely maneuver, goes more or less in a straight line and. The nose of a supercavitating torpedo uses gas nozzles that continually expel an. Under this program, the theory of highmachnumber underwater flows has been investigated and firstprinciples modeling of cavity development and body dynamics have been addressed. The torpedo model is then constrained from rigid body translation but free to expand and contract due to the applied pressure forces.
The cavity the bubble reduces the drag on the object and this makes supercavitation an attractive technology. However, implementing this technique requires clear understanding and precise control of supercavity behaviors under unsteady conditions in practical applications. Among those, one of the most strong factors is effect of a free. Ventilated supercavitation is a promising technique to achieve highspeed transport underwater by generating a gas bubble enclosing a moving object through ventilation. 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. Us navy is developing supersonic submarine that could. Shape optimization of the cavitator for a supercavitating torpedo. Optimum design of a supercavitating torpedo considering. Supercavitation presentation free download as powerpoint presentation.
A specific configuration of torpedo is obtained for required speed and supercavitation and the details of process are discussed thoroughly. Experimental investigation of ventilated supercavitation. Research progress of supercavitation hydrodynamics. At madex 2017, the international maritime defense industry exhibition held in october 2017 in busan, south koreas agency for defense development add stand was featuring. The problems include the generation,development and stability of supercavitation,hydrodynamic forces acting on the supercavitating vehicle,and the hydroballistics of vehicle. Design and development of a supercavitating torpedo body. The basic similarity parameters of the supercavitation flows are cavitation number and reynolds number, which are defined as. Launched from 533 mm torpedo tubes, the va 111 exits the tube at 50 knots 93 kmh.
Militarygfys is a place for sharing military moments from around the world and throughout history in the small, easy to share. Exaggerated diagram of supercavitation formation around a torpedo body. 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. Supercavitation is the use of a cavitation bubble to reduce skin friction drag on a submerged object and enable high speeds. Why arent supercavitating torpedoes the standard in the.