Journal articles: 'High speed propulsion'

1

Blount, Donald L., and Robert J. Bartee. "Design of Propulsion Systems for High-Speed Craft." Marine Technology and SNAME News 34, no. 04 (October 1, 1997): 276–92. http://dx.doi.org/10.5957/mt1.1997.34.4.276.

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The demand for increased speed in medium and large craft challenges the designer to select propulsion systems which meet performance requirements economically throughout ever-widening operational profiles. The combined hydrodynamic characteristics of hull and propulsors result in a speed-thrust relationship for the environment in which the vessel operates. This speed-thrust relationship requires unique values of power and RPM input for each type and number of propulsors. Power and RPM are also sensitive to the mode of operation of the vessel whether at constant speed, accelerating to a greater speed or towing an object. Most vessels utilize fixed-pitch submerged propellers. Surface propellers are fitted to vessels designed to perform at very high speeds and waterjetpropulsors are being utilized with increasing frequency on larger vessels with high-speed operational profile. This paper discusses brake horsepower (BHP) and propulsor RPM relationships for vessel speed requirements based on the hydrodynamic characteristics of three types of propulsors: submerged propellers, surface propellers and waterjets. An example of predicted vessel performance regarding speed, power and propulsor RPM is presented which includes engine characteristics and BHP versus RPM. This latter format depicts the differences in power demand for three types of propulsors on a monohull vessel with regard to engine characteristics.

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Glushchenko, M. D., and I. O. Goryunov. "Hybrid Propulsion Unit." World of Transport and Transportation 14, no. 3 (June 28, 2016): 72–79. http://dx.doi.org/10.30932/1992-3252-2016-14-3-6.

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The authors presented a conceptual idea of a high-speed mainline with a maximum speed of 400–450 km/h. The use of rotary engines requires more energy at high speeds, there are difficulties with current collection, wheel-rail adhesion, etc. At the same time, the use of a linear traction motor at low speeds is not justified from an economic point of view, but efficient at high speed in terms of operation. In this regard, an option of a combined or hybrid traction propulsion unit is offered, in which the positive aspects of previous models interfit.

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Srivastava, Shivank, Brandon M. Taravella, Jonathan R. Eastridge, and Kazim M. Akyuzlu. "Numerical Analysis of the Hydrodynamics of an Anguilliform-Like Propulsor for High Efficiency." Marine Technology Society Journal 56, no. 2 (April 27, 2022): 47–63. http://dx.doi.org/10.4031/mtsj.56.2.3.

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Abstract A numerical study is conducted to investigate the hydrodynamic performance of an anguilliform-like propulsor for high Reynolds number in laminar flow regimes. The undulating propulsor is an articulated, cylindrical body with dome-shaped end caps. The body undulates with prescribed kinematics designed for an ideal anguilliform swimming motion for highest hydrodynamic efficiency and no shed vortices in its wake. Simulations are performed for an ideal swimming speed in inviscid and viscous flow regimes, which are compared to an ideal swimming theory. Viscous flow simulations are performed for the same swimming speed, which corresponds to Reynolds number of 241,844. The swimming speed is then reduced to achieve zero net force corresponding to Reynolds number 183,796, at which the anguilliform is generating constant speed self-propulsion. The thrust and drag forces along with lateral power loss and propulsive efficiency are reported. The viscous effects did not change when the Reynolds number is reduced; however, there is a significant increase in the thrust produced due to undulatory motion. The propulsive efficiency is predicted to be higher than observed for live anguilliforms.

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Li, Bin Cheng, and Bing Han. "Simulation of the Application of Pneumatic Propulsion Method in Tourist Submarine." Applied Mechanics and Materials 43 (December 2010): 603–9. http://dx.doi.org/10.4028/www.scientific.net/amm.43.603.

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In order to realize propulsion system and oxygen system of tourist submarines be secure, eco-friendly, efficient, reliable, economical, a combination of ordinary air motor and ACM high-pressure air bottle is adopted for providing propulsion and oxygen. The calculation and selection of the appropriate air motor and high-pressure bottle are based on the propulsive requirement of a tourist submarine. A model consists of high-pressure bottle, air motor, propeller and the resistance of the tourist submarine is established in SimulationX. The underwater speed and it’s duration are obtained through calculation as the rev, thrust force, torque of the propeller, etc. The possibility of application of pneumatic propulsion method in tourist submarine is analysed. Results illustrate that: on the premise of lightened quality of the propulsion system, pneumatic propulsion method fulfills the required underwater speed and it’s duration.

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Gany, Alon. "INNOVATIVE CONCEPTS FOR HIGH-SPEED UNDERWATER PROPULSION." International Journal of Energetic Materials and Chemical Propulsion 17, no. 2 (2018): 83–109. http://dx.doi.org/10.1615/intjenergeticmaterialschemprop.2018027877.

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Kinnas, Spyros A. "An International Consortium on High-Speed Propulsion." Marine Technology and SNAME News 33, no. 03 (July 1, 1996): 203–10. http://dx.doi.org/10.5957/mt1.1996.33.3.203.

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Recent demands for higher speed ocean vehicles and, at the same time, for more efficient propulsion, have made the appearance of cavitation inevitable. Thus, contemporary hydrofoil or propeller blade designs must take advantage of controlled cavitation in order to increase the efficiency of propulsion. An International Consortium on Cavitation Performance of High-Speed Propulsors has been put together by the author. The ultimate objective of this effort is to develop a new generation of reliable and user-friendly computational tools for the analysis and systematic design of efficient cavitating hydrofoils or propulsors. Fifteen participants have joined this consortium thus far. They include research centers, propeller manufacturers, shipyards, and high-speed boat industries from the U.S., Europe, and Asia. An overview of the research plan and the approach for some of the research tasks are presented.

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LEE, Hsing-Juin, Yow-Jeng JONG, Li-Min CHANG, and Wen-Lin WU. "Propulsion Strategy Analysis of High-Speed Swordfish." TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES 52, no. 175 (2009): 11–20. http://dx.doi.org/10.2322/tjsass.52.11.

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BATRAK, D. V., D. V. NIKUSHCHENKO, and A. P. SENKOV. "Electric propulsion system for high-speed vessels." Elektrotekhnika, no. 11 (2022): 59–64. http://dx.doi.org/10.53891/00135860_2022_11_59.

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Bai, Hongfen. "Position Estimation of a PMSM in an Electric Propulsion Ship System Based on High-Frequency Injection." Electronics 9, no. 2 (February 6, 2020): 276. http://dx.doi.org/10.3390/electronics9020276.

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To improve the operating performance of electric propulsion ships, the permanent magnet synchronous motor is commonly used as the propulsion motor. Additionally, position estimation without sensors can further improve the application range of the propulsion motor and the estimated results can represent the redundancy of measured values from mechanical sensors. In this paper, the high-frequency (HF) injection algorithm combined with the second-order generalized integrator (SOGI) is presented on the basis of analyzing the structure of the electric propulsion ship and the vector control of the motors. The position and rotor speed were estimated accurately by the approximate calculation of q-axis currents directly related to the rotor position. Moreover, the harmonics in the estimated position were effectively reduced by the introduction of the second-order generalized integrator. Then, the rotor position estimation algorithm was verified in MATLAB/Simulink by choosing different low speeds including speed reversal, increasing speed, and increasing load torque. Finally, the correctness of the proposed improved high-frequency injection algorithm based on the second-order generalized integrator was verified by the experimental propulsion permanent magnet synchronous motor (PMSM) system at low speed.

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Rosato, Daniel A., Mason Thornton, Jonathan Sosa, Christian Bachman, Gabriel B. Goodwin, and Kareem A. Ahmed. "Stabilized detonation for hypersonic propulsion." Proceedings of the National Academy of Sciences 118, no. 20 (May 10, 2021): e2102244118. http://dx.doi.org/10.1073/pnas.2102244118.

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Future terrestrial and interplanetary travel will require high-speed flight and reentry in planetary atmospheres by way of robust, controllable means. This, in large part, hinges on having reliable propulsion systems for hypersonic and supersonic flight. Given the availability of fuels as propellants, we likely will rely on some form of chemical or nuclear propulsion, which means using various forms of exothermic reactions and therefore combustion waves. Such waves may be deflagrations, which are subsonic reaction waves, or detonations, which are ultrahigh-speed supersonic reaction waves. Detonations are an extremely efficient, highly energetic mode of reaction generally associated with intense blast explosions and supernovas. Detonation-based propulsion systems are now of considerable interest because of their potential use for greater propulsion power compared to deflagration-based systems. An understanding of the ignition, propagation, and stability of detonation waves is critical to harnessing their propulsive potential and depends on our ability to study them in a laboratory setting. Here we present a unique experimental configuration, a hypersonic high-enthalpy reaction facility that produces a detonation that is fixed in space, which is crucial for controlling and harnessing the reaction power. A standing oblique detonation wave, stabilized on a ramp, is created in a hypersonic flow of hydrogen and air. Flow diagnostics, such as high-speed shadowgraph and chemiluminescence imaging, show detonation initiation and stabilization and are corroborated through comparison to simulations. This breakthrough in experimental analysis allows for a possible pathway to develop and integrate ultra-high-speed detonation technology enabling hypersonic propulsion and advanced power systems.

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11

Tsutahara, M., and T. Kimura. "An Application of the Weis-Fogh Mechanism to Ship Propulsion." Journal of Fluids Engineering 109, no. 2 (June 1, 1987): 107–13. http://dx.doi.org/10.1115/1.3242629.

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A mechanism of hovering flight of small insects which is called the Weis-Fogh mechanism is applied to ship propulsion. A model of the propulsion mechanism is proposed, which is based on a two-dimensional model of the Weis-Fogh mechanism and consists of one or two wings in a square channel. The dynamic properties of the model are studied experimentally, and the propulsive efficiency obtained is as high as 75 percent. A model ship equipped with this propulsion mechanism was made, and working tests performed. The model ship sailed very smoothly and the moving speed of the wings was small compared with the advancing speed of the ship.

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12

Jackson, T. A., D. R. Eklund, and A. J. Fink. "High speed propulsion: Performance advantage of advanced materials." Journal of Materials Science 39, no. 19 (October 2004): 5905–13. http://dx.doi.org/10.1023/b:jmsc.0000041687.37448.06.

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13

Batrak, D. V., D. V. Nikushchenko, and A. P. Senkov. "An Electric-Propulsion System for High-Speed Vessels." Russian Electrical Engineering 93, no. 11 (November 2022): 739–42. http://dx.doi.org/10.3103/s1068371222110025.

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14

Karthigan, Ganesan, Sujoy Mukherjee, and Ranjan Ganguli. "Electromechanical dynamics and optimization of pectoral fin–based ionic polymer–metal composite underwater propulsor." Journal of Intelligent Material Systems and Structures 23, no. 10 (May 6, 2012): 1069–82. http://dx.doi.org/10.1177/1045389x12442010.

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Ionic polymer–metal composites are soft artificial muscle-like bending actuators, which can work efficiently in wet environments such as water. Therefore, there is significant motivation for research on the development and design analysis of ionic polymer–metal composite based biomimetic underwater propulsion systems. Among aquatic animals, fishes are efficient swimmers with advantages such as high maneuverability, high cruising speed, noiseless propulsion, and efficient stabilization. Fish swimming mechanisms provide biomimetic inspiration for underwater propulsor design. Fish locomotion can be broadly classified into body and/or caudal fin propulsion and median and/or paired pectoral fin propulsion. In this article, the paired pectoral fin–based oscillatory propulsion using ionic polymer–metal composite for aquatic propulsor applications is studied. Beam theory and the concept of hydrodynamic function are used to describe the interaction between the beam and water. Furthermore, a quasi-steady blade element model that accounts for unsteady phenomena such as added mass effects, dynamic stall, and the cumulative Wagner effect is used to obtain hydrodynamic performance of the ionic polymer–metal composite propulsor. Dynamic characteristics of ionic polymer–metal composite fin are analyzed using numerical simulations. It is shown that the use of optimization methods can lead to significant improvement in performance of the ionic polymer–metal composite fin.

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15

Chun, Kang Woo, Myongho Kim, and Jae-Jung Hur. "Development of a Marine LPG-Fueled High-Speed Engine for Electric Propulsion Systems." Journal of Marine Science and Engineering 10, no. 10 (October 14, 2022): 1498. http://dx.doi.org/10.3390/jmse10101498.

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As regulations on emissions from ships become stricter worldwide, new propulsion systems and the use of eco-friendly fuel are being introduced as alternative solutions. Therefore, many studies on electric propulsion systems using various power sources are being conducted. Conventional diesel propulsion systems are available from small to large scale, but in the case of LPG propulsion systems, some specifications are limited, and their application is impossible. In addition, due to the limitations of the companies participating in the development of small and medium-sized engines, marine empirical research into existing shore engines is required rather than developing new engines. In this study, a generator using LPG fuel was developed for such an eco-friendly electric propulsion system and tested in the field. Accordingly, a 230 kW-class waterjet type LPG engine for electric propulsion was developed and developed for patrol ships, which are small and medium-sized ships. A system that considers the marine environment was developed, and various data were recorded through test operation under various loads. The results of this study can be used for the development of various auxiliary engine systems, and the test operation procedure of this development can be applied to the development of small and medium-sized LPG engines of different capacities. In addition, it can have a big impact on the business of converting marine engines from onshore engines. However, the development costs and improving the efficiency are still areas to be further improved through future research.

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D'Ovidio, Gino, and Francesco Crisi. "High Speed Propulsion System for UAQ4 Magnetic Levitating Train." Materials Science Forum 721 (June 2012): 9–14. http://dx.doi.org/10.4028/www.scientific.net/msf.721.9.

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This paper presents the design of a novel high speed propulsion system for UAQ4 magnetic levitating train, the feasibility of which has been successfully tested and confirmed in laboratory. A direct-current linear stepper motor that uses permanent magnets distributed on the central beam of track as the stator and the direct current power supplied coils on-board the vehicle as the rotor is proposed and analyzed. The motor performances are evaluated by varying the system parameters by carrying out a finite element numerical model refined with experimental data. The main components of a real scale motor with speed up to 580 km/h for the UAQ4 train application is measured and discussed.

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Lee, Jinho, Kuo-Cheng Lin, and Dean Eklund. "Challenges in Fuel Injection for High-Speed Propulsion Systems." AIAA Journal 53, no. 6 (June 2015): 1405–23. http://dx.doi.org/10.2514/1.j053280.

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Gemmell, Brad J., Sean P. Colin, John H. Costello, and Kelly R. Sutherland. "A ctenophore (comb jelly) employs vortex rebound dynamics and outperforms other gelatinous swimmers." Royal Society Open Science 6, no. 3 (March 2019): 181615. http://dx.doi.org/10.1098/rsos.181615.

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Gelatinous zooplankton exhibit a wide range of propulsive swimming modes. One of the most energetically efficient is the rowing behaviour exhibited by many species of schyphomedusae, which employ vortex interactions to achieve this result. Ctenophores (comb jellies) typically use a slow swimming, cilia-based mode of propulsion. However, species within the genus Ocyropsis have developed an additional propulsive strategy of rowing the lobes, which are normally used for feeding, in order to rapidly escape from predators. In this study, we used high-speed digital particle image velocimetry to examine the kinematics and fluid dynamics of this rarely studied propulsive mechanism. This mechanism allows Ocyropsis to achieve size-adjusted speeds that are nearly double those of other large gelatinous swimmers. The investigation of the fluid dynamic basis of this escape mode reveals novel vortex interactions that have not previously been described for other biological propulsion systems. The arrangement of vortices during escape swimming produces a similar configuration and impact as that of the well-studied ‘vortex rebound’ phenomenon which occurs when a vortex ring approaches a solid wall. These results extend our understanding of how animals use vortex–vortex interactions and provide important insights that can inform the bioinspired engineering of propulsion systems.

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Shalahuddin, Lukman, Kartiko E. Putranto, and Dimas B. Eskayudha. "Propulsion System Design For The Indonesian Semi High Speed Train." Majalah Ilmiah Pengkajian Industri 13, no. 3 (January 1, 2020): 215–22. http://dx.doi.org/10.29122/mipi.v13i3.3851.

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This paper describes a study on the development of methodology to select the most appropriate technology, and the most optimum design and configuration for the propulsion system of the semi-high speed intercity train that will be operated on the Jakarta-Surabaya corridor. It also describes the method to calculate resistance loads Â and tractive forces and hence the power required to propel the train along the specified route within targeted time. Among the output of this study is a recommendation for the most optimum propulsion system with basic/ main parameters for main components such as diesel engine, traction motor and the possibility of Diesel Electric Multiple Unit (DEMU) Hybrid battery system.

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Steinberg, Daniel, Asher Bender, Ariell Friedman, Michael Jakuba, Oscar Pizarro, and Stefan Williams. "Analysis of Propulsion Methods for Long-Range AUVs." Marine Technology Society Journal 44, no. 2 (March 1, 2010): 46–55. http://dx.doi.org/10.4031/mtsj.44.2.3.

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AbstractUnderwater gliders use a buoyancy engine and symmetric wings to produce lift. During operation, gliders follow a saw-tooth trajectory, making them useful vehicles for profiling ocean chemistry. By operating at low speeds with low hotel loads, gliders achieve a high endurance. Man-portable, propeller-driven autonomous underwater vehicles (AUVs) are capable of level flight and can also follow terrain to yield high-quality benthic imagery. These platforms typically operate at high speeds with high hotel loads resulting in relatively low endurance. Although both vehicles are used to collect oceanographic data, constraints on how these vehicles are used differentiate the nature of data they collect. This article examines whether one method of propulsion can provide an intrinsic advantage in terms of horizontal range at low speed, regardless of sampling design. We employ first-principle analysis that concludes that either class of vehicle can be designed to achieve the same horizontal transit performance regardless of speed. This result implies that the choice of propulsion method should be driven exclusively by the application and operational requirements.

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Wilhite, A. W., and R. J. Shaw. "Technology development for high-speed civil transport." Aeronautical Journal 104, no. 1040 (October 2000): 467–71. http://dx.doi.org/10.1017/s000192400009196x.

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Abstract The National Aeronautics and Space Administration sponsored a joint High-Speed Research Programme with United States airframe and propulsion companies to provide the critical high-risk technologies for a Mach 2·4, 300 passenger civil transport. Laboratory and medium-scale tests provided promising results in meeting both the environmental and economic goals for a future High-Speed Civil Transport. However, before the technologies were integrated at large and full scale, the programme was cancelled because of global economic concerns of the US transport industry.

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Large, James, and Apostolos Pesyridis. "Investigation of Micro Gas Turbine Systems for High Speed Long Loiter Tactical Unmanned Air Systems." Aerospace 6, no. 5 (May 14, 2019): 55. http://dx.doi.org/10.3390/aerospace6050055.

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In this study, the on-going research into the improvement of micro-gas turbine propulsion system performance and the suitability for its application as propulsion systems for small tactical UAVs (<600 kg) is investigated. The study is focused around the concept of converting existing micro turbojet engines into turbofans with the use of a continuously variable gearbox, thus maintaining a single spool configuration and relative design simplicity. This is an effort to reduce the initial engine development cost, whilst improving the propulsive performance. The BMT 120 KS micro turbojet engine is selected for the performance evaluation of the conversion process using the gas turbine performance software GasTurb13. The preliminary design of a matched low-pressure compressor (LPC) for the proposed engine is then performed using meanline calculation methods. According to the analysis that is carried out, an improvement in the converted micro gas turbine engine performance, in terms of thrust and specific fuel consumption is achieved. Furthermore, with the introduction of a CVT gearbox, the fan speed operation may be adjusted independently of the core, allowing an increased thrust generation or better fuel consumption. This therefore enables a wider gamut of operating conditions and enhances the performance and scope of the tactical UAV.

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Park, Gisu, Jongryul Byun, Hojin Choi, Yuin Jin, Chul Park, and Kiyoung Hwang. "High Speed Propulsion System Test Research Using a Shock Tunnel." Journal of the Korean Society of Propulsion Engineers 18, no. 5 (October 1, 2014): 43–53. http://dx.doi.org/10.6108/kspe.2014.18.5.043.

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Kwon, Minchan, Youngjoon Yoo, Heeseong Hwang, and Junyoung Heo. "Development of Underwater Rocket Propulsion System for High-speed Cruises." Journal of the Korean Society of Propulsion Engineers 23, no. 3 (June 1, 2019): 112–18. http://dx.doi.org/10.6108/kspe.2019.23.3.112.

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Takaoka, Kiyoshi, and Takeshi Yamada. "Main Propulsion system for High Speed and Long-Distance Ferry." JOURNAL OF THE MARINE ENGINEERING SOCIETY IN JAPAN 32, no. 2 (1997): 110–19. http://dx.doi.org/10.5988/jime1966.32.110.

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Keith Clutter, J., and Wei Shyy. "COMPUTATION OF HIGH-SPEED REACTING FLOW FOR GUN PROPULSION APPLICATIONS." Numerical Heat Transfer, Part A: Applications 31, no. 4 (March 1997): 355–74. http://dx.doi.org/10.1080/10407789708914042.

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Pak, On Shun, Wei Gao, Joseph Wang, and Eric Lauga. "High-speed propulsion of flexible nanowire motors: Theory and experiments." Soft Matter 7, no. 18 (2011): 8169. http://dx.doi.org/10.1039/c1sm05503h.

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Han, Wei, Ting Shang, Min Su, Chengyong Gong, Rennian Li, and Bin Meng. "Direct Sailing Variable Acceleration Dynamics Characteristics of Water-Jet Propulsion with a Screw Mixed-Flow Pump." Applied Sciences 9, no. 19 (October 8, 2019): 4194. http://dx.doi.org/10.3390/app9194194.

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Strong nonlinearity and the relevance of time-varying dynamic parameters in the maneuverable process of water-jet propulsion were major problems encountered in the prediction of variable acceleration dynamics characteristics. The relationships between the thrust and rotation speed of a screw mixed-flow pump, drag and submerged speed of water-jet propulsion were obtained from flume experiments and numerical calculations, based on which a dynamic model of pump-jet propulsion was established in this paper. As an initial condition, the numerical solution of the submerged speed with respect to time was inputted to computational fluid dynamics (CFD) for unsteady calculation based on a user-defined function (UDF). Thus, the relationships between the acceleration, drag, net thrust, propulsion torque and efficiency with respect to time were revealed. The results indicate that the relationship between the thrust and rotational speed of a water-jet propeller is a quadratic function, which agrees well with the experimental values. The variation of submerged speed with respect to time satisfies a hyperbolic tangent function distribution. The acceleration increases sharply at the beginning and then decreases gradually to zero, especially at high rotation speeds of the water-jet pump. The variations in drag and propulsion efficiency with respect to time coincide with the step response of a second-order system with critical damping. The method and results of this study can give a better understanding of the changes in dynamic parameters such as velocity, acceleration, thrust, and drag during the acceleration of a pump-jet submersible and helped to estimate the effects of pump performance on water-jet propulsion kinetic parameters.

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Qin, Feng, Ying Lin, and Diqiang Lu. "Hardware-in-the-loop simulation of high-speed maglev transportation five-segment propulsion system based on dSPACE." Transportation Systems and Technology 4, no. 2 (September 13, 2018): 62–72. http://dx.doi.org/10.17816/transsyst20184262-72.

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Aim: For exploring and testing the key technology of high-speed maglev transportation propulsion control system, this paper designs and establishes a hardware-in-the-loop (HIL) real-time simulation system of the high-speed maglev transportation five-segment propulsion system. Materials and methods of the studies: According to the route conditions and propulsion segment division of Shanghai maglev demonstration and operation line, the real-time simulation platform based on dSPACE multiprocessor systems is implemented. The simulation system can achieve the functional simulation of all the high-power related equipment in the 5-segment area, including 8 sets of high-power converter units, 2 sets of medium-power converter units, 2 sets of low-power converter units, five-segment trackside switch stations and long-stator linear synchronous motors. The mathematical models of linear motors and converters are built in MATLAB/Simulink and System Generator, after compiling, they can be downloaded and executed in Field Programmable Logic Array (FPGA). All the interfaces connecting the simulation system to the propulsion control system physical equipment use real physical components as in the field, such as analog I/O, digital I/O, optical signals and Profibus. Results: By using CPU+FPGA hardware configuration, the simulation steps are greatly shortened and the response speed and accuracy of real-time simulation system are improved. The simulation system can simulate multiple operating modes such as multi-segment, multi-vehicle, double-track, double-feeding, step-by-step stator section changeover, and so on. The simulation results show that the maximum speed of the simulation system can reach 500 km/h. Conclusion: This HIL system can provide detailed real-time on-line test and verification of high speed maglev propulsion control system.

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Alexander, Keith. "Features of the Wakes of Partly Immersed Wheels." Marine Technology and SNAME News 36, no. 02 (April 1, 1999): 112–25. http://dx.doi.org/10.5957/mt1.1999.36.2.112.

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The wakes of partly immersed wheels and paddlewheels are described. The wave trains are compared with boat wakes and are classified into displacement, transition and planing types. The effects that these wake forms can have on a wheel that is being used as a propulsion device are discussed. A significant feature of wheels at high rotational speeds is the stern fountain. Its formation and effects are discussed. Another feature is the overwhelming bow wave which is sometimes present at planing speeds. This is described and factors contributing to its formation are discussed. The control of this bow wave is noted as important particularly for high-speed paddlewheels since its presence limits the speed of operation. It is concluded that these wake features need to be taken into consideration in the design of wheel type propulsion devices. This study is part of a project that developed a type of paddlewheel that supports a load dynamically as it travels at speed over the water surface.

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Yurkov, Bohdan, Oleksandr Petrenko, Dmytro Voronovskyi, and Troyan Andrey. "TEST RESULTS OF A HIGH-SPEED SOLENOID VALVE FOR THE ELECTRIC PROPULSION FEED SYSTEM." Journal of Rocket-Space Technology 29, no. 4 (November 17, 2021): 72–80. http://dx.doi.org/10.15421/452107.

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Today in the world there are many electric propulsion systems based on the different types of thrusters. Most of them used gaseous propellent. Typical Electric propulsion system (EPS) consists of following main subsystems: the electric propulsion thruster that creates thrust; the power-processing and control unit which provides energy to all subsystems; the storage and feed system that performs functions of storing working substance in the tank and supplying the required amount of working substance to the thruster; Solenoid valve is a part of storage and feed systems. The feed system is an essential part of any electric propulsion system. The life cycle of the feed system is largely determined by lifetime of the valves and the amount of working substance in tank. Whereas the amount of working substance is selected based on the requirements for each specific mission valve parameters must be satisfying for various missions. Accordingly, the valves must have low power consumption, high reliability with a long lifetime (more than 106 cycles), low weight and dimensions. Solenoid valve is an electromechanical device that consists of moving part controlled by an electromagnet. Movement of the movable element and the seal are key parts of valve reliability. Presented solenoid valve design uses two membranes, which perform the function of centering the moving element and with the spring provide the required closing speed and the seal of the valve. The paper presents the problem of selecting critical elements that affect the solenoid valve's performance, procedure and test results required for the qualification of space equipment. Manufactured valve was successfully tested (vibration testing, response time testing with inlet pressure change, response time testing at different operating voltages, dependence of the valve actuation current on the operating voltage, temperature testing, lifetime tests) separately and as part of XFS according to the ECSS standards. As well as the successful implementation of presented valve into the flight xenon feed system for electric propulsion.

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Ispir, Ali Can, Pedro Miguel Gonçalves, and Bayindir H. Saracoglu. "Analysis of a combined cycle propulsion system for STRATOFLY hypersonic vehicle over an extended trajectory." MATEC Web of Conferences 304 (2019): 03001. http://dx.doi.org/10.1051/matecconf/201930403001.

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Hypersonic civil aviation is an important enabler for extremely shorter flight durations for long-haul routes and using unexploited flight altitudes. Combined cycle engine concepts providing extended flight capabilities, i.e. propelling the aircraft from take-off to hypersonic speeds, are proposed to achieve high-speed civil air transportation. STRATOFLY project is a continuation of former European efforts in hypersonic research and aims at developing a commercial reusablevehicle for cruise speed of Mach 8 at stratospheric altitudes as high as 35 km above ground level. The propulsion plant of STRATOFLY aircraft consists of combination of two different type of engines: an array of air turbo rockets and a dualmode ramjet/scramjet. In the present study, 1D transient thermodynamic simulations for this combined cycle propulsion plant have been conducted between Mach 0 to 8 by utilizing 1D inviscid flow transport relations, numerical tools availablein EcosimPro software platform and the European Space Propulsion System Simulation libraries. The optimized engine parameters are achieved by coupling EcosimPro software with Computer Aided Design Optimization which is a differential evolution algorithm developed at the von Karman Institute.

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Hassan, Khairul, Maurice F. White, and Cosmin Ciorta. "Effect of Container Stack Arrangements on the Power Optimization of a Container Ship." Journal of Ship Production and Design 28, no. 01 (February 1, 2012): 10–19. http://dx.doi.org/10.5957/jspd.2012.28.1.10.

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When considering the design of a ship, an important objective is to always try and develop one that allows for maximum cargo capacity with the lowest propulsion power requirement while providing a sufficient amount of strength and stability for its safe operation. The ship with the lowest propulsion power consumes the least amount of fuel and produces the lowest amount of exhaust gas that may be harmful to the environment. In some cases, the aerodynamic resistance can be neglected, but for a high speed vessel such as a modern containership, the air resistance can be in the range of 2% to 10% of the total resistance. Aerodynamic resistance can therefore have a significant effect on power requirements and is strongly influenced by the height, breadth, and the number of container stacks on the deck. The freeboard, beam of the ship, deck house design, ship speed, wind speed, and water flow direction will also contribute significantly to a ship's resistance and required propulsive power. This paper outlines the application of computational fluid dynamic simulation as a design tool to find a strategy for the optimal arrangement of the container stacks on deck so that the vessel uses the lowest effective propulsion power to achieve a fuel efficient ship. It is deduced that an optimal stack arrangement can reduce air resistance by about 30%.

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Drummond, J. Philip. "Methods for Prediction of High-Speed Reacting Flows in Aerospace Propulsion." AIAA Journal 52, no. 3 (March 2014): 465–85. http://dx.doi.org/10.2514/1.j052283.

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Liu, Hanlin, Fuxian Gong, and Oscar Curet. "Unleashing the Potential of Undulating Fin Propulsion Using a Biomimetic Robotic Vessel." Marine Technology Society Journal 51, no. 5 (September 1, 2017): 79–93. http://dx.doi.org/10.4031/mtsj.51.5.7.

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AbstractUndulating fins are an excellent propulsion model for highly maneuverable underwater vehicles, due to their rich locomotor capabilities and high efficiency at moderate speed. In this study, we designed, developed, and tested a self-contained, free-swimming robotic device, the KnifeBot, to emulate the locomotor behaviors of knifefish, a typical fish that excels in using this type of propulsion. This novel biomimetic underwater vehicle uses an elongated ribbon-like fin composed of 16 fin rays interconnected by a compliant membrane as the propulsor. It features a slender 3D printed hull, 16 DC motors for actuating the fin rays, 2 Li-Ion batteries for providing power, wireless radio communication, and various sensors to measure acceleration, orientation, inside temperature, pressure and to detect leakage. We used this robotic device in two experimental sets: (1) the robot without pectoral fins to perform forward swimming, reversed swimming, and hovering maneuvers and (2) the robot with a pair of pectoral fins with fixed angle of attack (−5°) to perform forward swimming. In this paper, we focus on the design, implementation, and control of the robot. We also present the results of forward swimming velocity, power consumption, and Euler orientation angles of the robot with and without pectoral fins. Our results show that the cost of transport follows a V-shape trend with the lowest point at low swimming speed, indicating the undulating fin propulsion is more efficient at low speeds. For the cases studied, the Strouhal number, St, ranges from 0.5 to 0.2 with the best cost-of-transport corresponding to St = 0.2. We found that the airfoil-like pectoral fins at small negative angles of attack slightly slow down the speed of the robotic vessel and reduce its pitch angle. The robot can take advantage of the pectoral fins to control its maneuver from swimming at the water surface to rapid diving. Our findings demonstrate that undulating fin-based propulsion has the potential to enhance the mobility and performance of underwater vehicles navigating in complex environments.

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Sobel, D. R., and L. J. Spadaccini. "Hydrocarbon Fuel Cooling Technologies for Advanced Propulsion." Journal of Engineering for Gas Turbines and Power 119, no. 2 (April 1, 1997): 344–51. http://dx.doi.org/10.1115/1.2815581.

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Storable hydrocarbon fuels that undergo endothermic reaction provide an attractive heat sink for future high-speed aircraft. An investigation was conducted to explore the endothermic potential of practical fuels, with inexpensive and readily available catalysts, under operating conditions simulative of high-speed flight applications. High heat sink capacities and desirable reaction products have been demonstrated for n-heptane and Norpar 12 fuels using zeolite catalysts in coated-tube reactor configurations. The effects of fuel composition and operating condition on extent of fuel conversion, product composition, and the corresponding endotherm have been examined. The results obtained in this study provide a basis for catalytic-reactor/heat-exchanger design and analysis.

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HU, DAVID L., and JOHN W. M. BUSH. "The hydrodynamics of water-walking arthropods." Journal of Fluid Mechanics 644 (February 10, 2010): 5–33. http://dx.doi.org/10.1017/s0022112009992205.

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We present the results of a combined experimental and theoretical investigation of the dynamics of water-walking insects and spiders. Using high-speed videography, we describe their numerous gaits, some analogous to those of their terrestrial counterparts, others specialized for life at the interface. The critical role of the rough surface of these water walkers in both floatation and propulsion is demonstrated. Their waxy, hairy surface ensures that their legs remain in a water-repellent state, that the bulk of their leg is not wetted, but rather contact with the water arises exclusively through individual hairs. Maintaining this water-repellent state requires that the speed of their driving legs does not exceed a critical wetting speed. Flow visualization reveals that the wakes of most water walkers are characterized by a series of coherent subsurface vortices shed by the driving stroke. A theoretical framework is developed in order to describe the propulsion in terms of the transfer of forces and momentum between the creature and its environment. The application of the conservation of momentum to biolocomotion at the interface confirms that the propulsion of water walkers may be rationalized in terms of the subsurface flows generated by their driving stroke. The two principal modes of propulsion available to small water walkers are elucidated. At driving leg speeds in excess of the capillary wave speed, macroscopic curvature forces are generated by deforming the meniscus, and the surface behaves effectively as a trampoline. For slower speeds, the driving legs need not substantially deform the surface but may instead simply brush it: the resulting contact or viscous forces acting on the leg hairs crossing the interface serve to propel the creature forward.

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Qiu, Chengcheng, Qiaogao Huang, and Guang Pan. "Prediction of Cavitation Performance over the Pump-Jet Propulsor Using Computational Fluid Dynamics and Hybrid Deep Learning Method." Journal of Marine Science and Engineering 10, no. 7 (July 2, 2022): 918. http://dx.doi.org/10.3390/jmse10070918.

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The cavitation performance of an oblique flow field is different from that under a pure axial flow field. This study analyzed the hydrodynamic performance, bearing force, and tip clearance flow field under different rotating speeds and different cavitation numbers in an oblique flow field. Furthermore, this study proposed a hybrid deep learning model CNN-Bi-LSTM to quickly and accurately predict the bearing force of a pump-jet propulsor (PJP), which will solve the problem of time-consuming calculation and consumption of considerable computing resources in traditional computational fluid dynamics. The Shear–Stress–Transport model and Reynolds-averaged Navier–Stokes equations were utilized to procure the training and testing datasets. The training and testing datasets were reasonably divided in the ratio of 7:3. The results show that the propulsion efficiency decreased more obviously under higher rotating speed conditions, with a maximum decrease of up to 13.59%. The small cavitation numbers 1.4721 and high oblique angle significantly impacted the efficiency reduction; the maximum efficiency loss exceeded 20%. Thus, a small cavitation number 1.4721 is extremely detrimental to the propulsion efficiency of the PJP due to the large cavitation area. Moreover, the intensity of the tip clearance vortex continuously increased with the rotating speed. The CNN-Bi-LSTM deep model successfully predicted the phase difference and trend change of the propulsor bearing force under different conditions. The prediction difference was large at the crest and trough of the bearing force, but it is within the acceptable error range.

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Reisz, Aloysius I. "To Go Beyond." Mechanical Engineering 130, no. 11 (November 1, 2008): 42–45. http://dx.doi.org/10.1115/1.2008-nov-2.

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This article discusses experiments with an advanced electromagnetic engine that aims for high-speed, long-distance transportation to reach farther into space. Experimental work at Marshall Space Flight Center in Alabama is attempting to develop an electromagnetic engine designed to achieve higher velocities than current space-engine options and to last longer, too. Space engines with higher specific impulse will sense new science from deep space exploration quicker. In a way, higher specific impulse quickens our intelligence acquisition. Reisz Engineers and the University of Michigan are investigating the propulsive performances of an experimental advanced electromagnetic engine configuration. This electromagnetic propulsion configuration has a magnetic nozzle and the engine performance can be throttled. Electromagnetic propulsion systems can also be configured for operations in Earth space environment, and for lunar robotic and lunar mapping missions. Electromagnetic and fusion space engines promise fast and reliable propulsion systems, which will be needed if mankind is to pursue its exploration of the outer realms of our solar system and beyond.

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Janhunen, P., A. A. Quarta, and G. Mengali. "Electric solar wind sail mass budget model." Geoscientific Instrumentation, Methods and Data Systems 2, no. 1 (February 19, 2013): 85–95. http://dx.doi.org/10.5194/gi-2-85-2013.

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Abstract. The electric solar wind sail (E-sail) is a new type of propellantless propulsion system for Solar System transportation, which uses the natural solar wind to produce spacecraft propulsion. The E-sail consists of thin centrifugally stretched tethers that are kept charged by an onboard electron gun and, as such, experience Coulomb drag through the high-speed solar wind plasma stream. This paper discusses a mass breakdown and a performance model for an E-sail spacecraft that hosts a mission-specific payload of prescribed mass. In particular, the model is able to estimate the total spacecraft mass and its propulsive acceleration as a function of various design parameters such as the number of tethers and their length. A number of subsystem masses are calculated assuming existing or near-term E-sail technology. In light of the obtained performance estimates, an E-sail represents a promising propulsion system for a variety of transportation needs in the Solar System.

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Powell, James, Gordon Danby, John Morena, Thomas Wagner, and Charles Smith. "MAGLEV 2000 Urban Transit System." Transportation Research Record: Journal of the Transportation Research Board 1838, no. 1 (January 2003): 58–63. http://dx.doi.org/10.3141/1838-08.

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The MAGLEV 2000 (M2000) of Florida Corporation has designed magnetic levitation (maglev) and propulsion technology for high-speed intercity transportation systems capable of operating at speeds in excess of 300 mph. This high-speed technology can be adapted for slower-speed urban transit operations with operating speeds of 30 to 120 mph. M2000 preliminary baseline urban transit designs and essential criteria for a maglev technology to operate safely and efficiently in an urban transit environment are discussed. M2000 uses superconducting magnets on the vehicle, interacting with aluminum coils in the guideway for levitation, stability, and propulsion. The coils are completely encapsulated in polymer concrete panels, which are attached to the sides of a narrow-beam guideway. The vehicle straddles the beam with a 6-in.gap between the guideway surface and vehicle. Propulsion is provided through the linear synchronous motor coils and powered by alternating electrical current. The large clearance between vehicles and guideway with the superconducting M2000 magnet system ensures low-cost guideway construction because of more leeway with construction tolerances. These large clearances allow system operations under snow and ice conditions. The magnetic switch also allows for efficient off-line stations and permits increased train frequencies and operation of express trains without delays from locally stopping trains. Most of the components for a M2000 operating system have been constructed. A review is presented of manufacturing techniques, operating requirements, and performance results for a maglev transit project.

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Park, Chan Bae, Byung Song Lee, Jae Hee Kim, Jun Ho Lee, and Hyung Woo Lee. "A Study on the Structure of Linear Synchronous Motor for 600km/h Very High Speed Train." Applied Mechanics and Materials 416-417 (September 2013): 317–21. http://dx.doi.org/10.4028/www.scientific.net/amm.416-417.317.

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Recently, an interest in a hybrid system combining only the merits of the conventional wheel-rail system and Maglev propulsion system is growing as an alternative to high-speed maglev train. This hybrid-type system is based on wheel-rail method, but it enables to overcome the speed limitation by adhesion because it is operated by a non-contact method using a linear motor as a propulsion system and reduce the overall construction costs by its compatibility with the conventional railway systems. Therefore, a comparative analysis on electromagnetic characteristics according to the structural combinations on the stator-mover of Linear Synchronous Motor (LSM) for Very High Speed Train (VHST) maintaining the conventional wheel-rail method is conducted, and the structure of coreless superconducting LSM suitable for 600 km/h VHST is finally proposed in this paper.

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Paolucci, Libero, Emanuele Grasso, Francesco Grasso, Niklas König, Marco Pagliai, Alessandro Ridolfi, Andrea Rindi, and Benedetto Allotta. "Development and testing of an efficient and cost-effective underwater propulsion system." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 233, no. 10 (February 25, 2019): 1309–28. http://dx.doi.org/10.1177/0959651819829627.

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Underwater vehicle propulsion performed by exploiting electrical motor is in general the most flexible solution and it is growing in popularity because of its high efficiency both at high and at low advance speed, quick and simple deployment, low costs, and encumbrance. In the present work, permanent magnet synchronous motors for underwater propulsion are proposed. In particular, advanced sensorless control techniques of permanent magnet synchronous motors permit reduced costs, high reliability, and performances. When dealing with small autonomous underwater vehicle propulsion, such devices are hard to find in the market. Hence, the authors focused the research in the development of a system able to perform a reliable rotational speed and torque sensorless estimation. The design and implementation of a complete solution for underwater propulsion are presented as well as a novel rotor polarity identification technique exploiting a high-frequency injection control. Pool tests for the identification of the performances and of the dynamic parameters of the propulsion system are presented. Finally, the possibility of operating a sensorless estimation of the thrust and torque exerted by the propeller and pool test measurements are presented. These features could be exploited to improve navigation accuracy and involves obvious benefits in terms of cost reduction and reliability of the system.

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Lu, Jiaxin, Yang Lu, Jinchao Ma, and Junjie Wang. "Numerical investigation of the wake transition and aerodynamic efficiency of the two-dimensional propulsive wing." AIP Advances 12, no. 12 (December 1, 2022): 125013. http://dx.doi.org/10.1063/5.0134927.

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The propulsive wing is a new concept wing of automatic propulsion with high lift coefficients and has great application value in plant protection and forest fire control. The propulsive wing wake is a reverse Bénard–von Kármán (RBvK) vortex street, which is considered a thrust-generating wake. The wake structure will change greatly at high angles of attack and lead to changes in the aerodynamic performance of the propulsive wing. To explore the optimal working range and the wake characteristics of the propulsive wing, the wake transition and aerodynamic efficiency of the propulsive wing in cruise are numerically studied. The results indicate that there are three types of structures for the propulsive wing wake. When α ≤ 20°, the wake transits from the RBvK vortex street to the critical state with the increase in cruise speed, and the Strouhal number approaches 1.9. The critical wake region decreases gradually with the increase in the angle of attack. The maximum propulsive efficiency is 0.17 at a cruise speed of 15 m/s. When α > 20°, the wake transits directly from the RBvK vortex street to the Bénard–von Kármán (BvK) vortex street and the Strouhal number approaches 0.34. The maximum propulsive efficiency appears at a cruise speed of 10 m/s, which is close to the BvK vortex street boundary. Before entering the stall state, the lift efficiency of the propulsive wing increases with the increase in cruise speed and angle of attack, up to 3–5.

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Yalavarthy, Uma Ravi Sankar, and Venkata Siva Krishna Rao Gadi. "Indirect Space Vector Modeling of Asynchronous Motor for High-Speed Electric Vehicle Propulsion." Journal Européen des Systèmes Automatisés 55, no. 1 (February 28, 2022): 35–48. http://dx.doi.org/10.18280/jesa.550104.

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This paper presents a high performance squirrel-cage asynchronous motor (ASM) drive, proposed for high-speed electric vehicle (EV) propulsion. This is an indirect space vector control (IDSVC) scheme in the rotor flux frame of reference, in which the modeling is based on synchronously rotating coordinate system transformation. Space vector pulse width modulation (SVPWM) inverter fetches the controlled stator direct and quadrature axis responses from the speed and current controllers and supply necessary voltages to stator of ASM. The output voltage waveforms of SVPWM inverter are not sinusoidal in nature, which allows undesired harmonics at high frequency of operation. This due to inconsistent switching frequency. A second-order low-pass (SOLP) RLC filter with Butterworth approximation and was designed and connected in series with SVPWM inverter to grab harmonic free speed and torque profile during high speed operations. Similarly, another SOLP with a quality factor equal to 2 is designed and speed profiles of both filters are compared. The system is developed and simulated in MATLAB/SIMULINK to observe the speed and torque tracking capabilities. Simulation results show that the performance of drive under steady and dynamic states were good with Butterworth filter approximation with robust IDSVC scheme adopted over wide range speed-drive curve.

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Thornhill, Eric, Brian Veitch, and Neil Bose. "Dynamic Instability of a High-Speed Planing Boat Model." Marine Technology and SNAME News 37, no. 03 (July 1, 2000): 146–52. http://dx.doi.org/10.5957/mt1.2000.37.3.146.

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A series of bare-hull resistance and self-propulsion tests were carried out on a 1/8 scale model of a 11.8 m long, waterjet-propelled planing hull in the clear water towing tank at the National Research Council of Canada's Institute for Marine Dynamics. The bare-hull resistance tests, performed with the waterjet inlets closed, spanned a range of eight model velocities and nine ballast conditions consisting of three displacements each with three positions of the longitudinal center of gravity. The hull was then fitted with two model waterjet thrusters and tested over the same speeds and ballast conditions. Dynamic instability, or porpoising, was seen during certain high-speed tests. A discussion of this behavior and its relation to published dynamic stability limits is given.

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Samoilescu, Gheorghe, Dumitru Iorgulescu, Robert Mitrea, and Laura D. Cizer. "Propulsion Systems in Marine Navigation." International conference KNOWLEDGE-BASED ORGANIZATION 24, no. 3 (June 1, 2018): 78–82. http://dx.doi.org/10.1515/kbo-2018-0140.

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Abstract This paper presents variants of propulsion systems as the main factor in the analysis and design of the power system of a sea-going or river vessel; this topic is also under research study within two doctoral theses. The analysis of the ship - main propulsion- thruster assembly is made according to the requirements imposed by the market economy. The parameters to be considered when choosing a propulsion system are: the cost of the investment, the specific cost of transport that depends both on the specific fuel consumption and on the number and level of pay of the crew members operating the propulsion system, the propulsion efficiency, the high safety in handling, and the control accessibility during operation. The Pod and Azipod propulsion systems are analyzed in terms of advantages and disadvantages compared to conventional propulsion systems. The azimuth thrusters can ensure maximum push in any direction regardless the speed of the ship, and thus can change the course of the ship according to its handling needs. The azimuth thrusters do not only operate in horizontal but also in oblique angles, providing the ship with great maneuverability, even at low speeds, where classical rudder systems have poor performance

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Jami’in, M. A., M. B. Rahmat, P. P. A. Nugroho, M. Santoso, and E. Julianto. "The Control of PMSM Motor to Drive Propeller in Ship Propulsion System." IOP Conference Series: Earth and Environmental Science 1081, no. 1 (September 1, 2022): 012005. http://dx.doi.org/10.1088/1755-1315/1081/1/012005.

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Abstract Electric propulsion has advantages such as high maneuverability, good safety and reliability, being able to operate optimally with a control system. It is a future green technology which is environmentally friendly. The application of electric propulsion for ship is that the propeller is driven by using electric motor by regulating speed and/or torque. in this research, an permanent magnet synchronous motor (PMSM) is used to drive propeller of ship propulsion. The controller of proportional integral (PI) scheme is proposed to drive electric motor. The method of Ziegler Nichols stability margin tuning rule algorithm is performed to search the controller parameters. The optimal working point of propeller is determined by the cross intersection between the propeller loading curve to the coefficient of thrust curve of open water test propeller. The speed from the result of propeller working point analysis is set as control input reference. Based on the results of simulation, the proposed control of electric propulsion using PMSM motor is able to achieve the reference of speed.

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Riggins, David W. "Analysis of the Magnetohydrodynamic Energy Bypass Engine for High-Speed Airbreathing Propulsion." Journal of Propulsion and Power 20, no. 5 (September 2004): 779–92. http://dx.doi.org/10.2514/1.4980.

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Varyani, K., and P. Krishnankutty. "Stopping manoeuvre of high speed vessels fitted with screw and waterjet propulsion." Journal of Marine Engineering & Technology 8, no. 1 (January 2009): 11–19. http://dx.doi.org/10.1080/20464177.2009.11020215.

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Journal articles on the topic 'High speed propulsion'

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