Artículos de revistas: "Propulsion systems"

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Fish, Frank E. "Advantages of Natural Propulsive Systems". Marine Technology Society Journal 47, n.º 5 (1 de septiembre de 2013): 37–44. http://dx.doi.org/10.4031/mtsj.47.5.2.

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AbstractThe screw propeller has been the mainstay of marine propulsion, but new developments in biomimetic propulsion can provide advantages in terms of speed, maneuverability, efficiency, and stealth. The diversity of aquatic animals provides designs for drag-based paddling and lift-based oscillatory hydrofoils that can be incorporated into engineered propulsive systems for enhanced performance. While the screw propeller will remain the prominent propulsive device, the choice of alternative biomimetic propulsive systems will be dependent on particular applications, where the specifications dictate improved performance criteria.

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2

Kaul, Stefan, Paul Mertes y Lutz Müller. "Application-optimised propulsion systems for energy-efficient operation". Ciencia y tecnología de buques 5, n.º 9 (23 de julio de 2011): 87. http://dx.doi.org/10.25043/19098642.53.

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Today, optimal propellers are designed by using advanced numerical methods. Major revolutionary improvements cannot be expected. More essential are the design conditions and the optimal adaptation of the propulsion system according to the operational requirements. The selection and optimisation of the propulsion system based on a systematic analysis of the ship’s requirements and the operation profile are the prerequisites for reliable and energy-efficient propulsion. Solutions are presented, which accommodate these issues with a focus on steerable rudderpropellers. Considerations include the efficiency potential of the propulsor itself, optimisation of the engine propeller interaction, and optimisation of a demandresponsive energy supply. The propeller-thruster interaction is complex, but offers some potential for optimisation. Results of examinations show this. The power distribution between multiple propellers at high loads of limited propeller diameters increases the efficiency. This can be done by double-propeller systems like the SCHOTTEL TwinPropeller or by distributing the power on several thrusters. This distributed propulsion offers economic operation and an increased lifetime by means of the demandresponsive use of energy. An efficiency-optimized electric motor instead of the upper gear box reduces the mechanical losses in the case of diesel-electric propulsion. An example: the SCHOTTEL CombiDrive.

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3

Pulatov, Valentine. "Magnetic propulsion systems". Progress in Aerospace Sciences 37, n.º 3 (abril de 2001): 245–61. http://dx.doi.org/10.1016/s0376-0421(01)00006-9.

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4

Achkasov, A. N., G. I. Grechko y V. A. Shishkin. "Nuclear propulsion systems". Atomic Energy 103, n.º 1 (julio de 2007): 532–36. http://dx.doi.org/10.1007/s10512-007-0084-1.

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5

Leśniewski, Wojciech, Daniel Piątek, Konrad Marszałkowski y Wojciech Litwin. "Small Vessel with Inboard Engine Retrofitting Concepts; Real Boat Tests, Laboratory Hybrid Drive Tests and Theoretical Studies". Energies 13, n.º 10 (20 de mayo de 2020): 2586. http://dx.doi.org/10.3390/en13102586.

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The development of modern technologies and their increasing availability, as well as the falling costs of highly efficient propulsion systems and power sources, have resulted in electric or hybrid propulsions systems’ growing popularity for use on watercraft. Presented in the paper are design and lab tests of a prototype parallel hybrid propulsion system. It describes a concept of retrofitting a conventionally powered nine meter-long vessel with the system, and includes results of power and efficiency measurements, as well as calculations of the vessel’s operating range under the propulsion of its electric motor. The concept of adding of a solar panels array was studied.

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6

Ibrahim, K., S. Sampath y D. Nalianda. "Voltage synchronisation for hybrid-electric aircraft propulsion systems". Aeronautical Journal 125, n.º 1291 (22 de julio de 2021): 1611–30. http://dx.doi.org/10.1017/aer.2021.56.

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AbstractIncreasing demand for commercial air travel is projected to have additional environmental impact through increased emissions from fuel burn. This has necessitated the improvement of aircraft propulsion technologies and proposal of new concepts to mitigate this impact. The hybrid-electric aircraft propulsion system has been identified as a potential method to achieve this improvement. However, there are many challenges to overcome. One such challenges is the combination of electrical power sources and the best strategy to manage the power available in the propulsion system. Earlier methods reviewed did not quantify the mass and efficiency penalties incurred by each method, especially at system level. This work compares three power management approaches on the basis of feasibility, mass and efficiency. The focus is on voltage synchronisation and adaptation to the load rating. The three methods are the regulated rectification, the generator field flux variation and the buck-boost. This comparison was made using the propulsion system of the propulsive fuselage aircraft concept as the reference electrical configuration. Based on the findings, the generator field flux variation approach appeared to be the most promising, based on a balance of feasibility, mass and efficiency, for a 2.6MW system.

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7

Islam, Mohammed F., Brian Veitch, Neil Bose y Pengfei Liu. "Numerical Study of Hub Taper Angle on Podded Propeller Performance". Marine Technology and SNAME News 43, n.º 01 (1 de enero de 2006): 1–10. http://dx.doi.org/10.5957/mt1.2006.43.1.1.

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Presently, the majority of podded propulsion systems are of the pulling type, because this type provides better hydrodynamic efficiency than the pushing type. There are several possible explanations for the better overall performance of a puller-type podded propulsor. One is related to the difference in hub taper angle. Puller and pusher propellers have opposite hub taper angles, hence different hub and blade root shape. These differences cause changes in the flow condition and possibly influence the overall performance. The current study focuses on the variation in performance of pusher and puller propellers with the same design of blade sections, but different hub taper angles. A hyperboloidal low-order source-doublet steady/unsteady time domain panel method code, PROPELLA, was modified and used to evaluate effects of hub taper angle on the open water propulsive performance of some fixed-pitch screw propellers used in podded propulsion systems. Major findings include good agreement between predictions using the modified code and measurements, significant effects of hub taper angle on propulsive performance of tapered hub propellers, and noticeable effects of hub taper angle on sectional pressure distributions of tapered hub propeller blades.

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8

Arias, Jonathan, Francisco Martinez, Edgar Cando y Esteban Valencia. "Towards More Efficient Electric Propulsion UAV Systems Using Boundary Layer Ingestion". Drones 7, n.º 12 (21 de noviembre de 2023): 686. http://dx.doi.org/10.3390/drones7120686.

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The implementation of distributed propulsion and boundary layer ingestion for unmanned aerial vehicles represents various challenges for the design of embedded ducts in blended wing body configurations. This work explores the conceptual design and evaluation of DP configurations with BLI. The aerodynamic integration of each configuration is evaluated following a proposed framework, including simulation analysis. Power saving coefficient and propulsive efficiency were compared against a baseline podded case. The results show the optimal propulsion configuration for the BWB UAV obtaining 3.95% of power benefit and propulsive efficiency (ηp>80%). Indeed, the aerodynamic integration effects for the proposed design maintain the BWB’s aerodynamic efficiency, which will contribute to longer endurance and better performance.

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9

Gallops, G. W., C. F. Weiss y R. A. Carlton. "Integrated Propulsion System Requirements for Control of STOVL Aircraft". Journal of Engineering for Gas Turbines and Power 113, n.º 1 (1 de enero de 1991): 60–67. http://dx.doi.org/10.1115/1.2906531.

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This paper describes an evaluation of propulsion system requirements and capability for a Short Take-Off/Vertical Landing (STOVL) aircraft employing modulation of the propulsive lift distribution for pitch and roll control in hover. The effects of propulsive lift nozzle configuration and propulsion system dynamic response were evaluated using a combined system simulation consisting of a six degree of freedom aircraft model, engine model, and integrated flight/propulsion control. The response and stability of propulsive lift control are compared with control by reaction jets supplied by engine bleed. Aircraft performance is demonstrated in simulated STOVL maneuvers using a dynamic pilot model. The conclusion of this study is that propulsive lift control of aircraft pitch and roll is feasible and can provide as much as a 10 percent increase in engine lift rating over systems that employ reaction control alone. The dynamic response of practical propulsive lift configurations, however, is less than that of reaction control configurations, which must be offset through integration of the propulsion system and its control.

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10

Kolodziejski, Marcin y Iwona Michalska-Pozoga. "Battery Energy Storage Systems in Ships’ Hybrid/Electric Propulsion Systems". Energies 16, n.º 3 (19 de enero de 2023): 1122. http://dx.doi.org/10.3390/en16031122.

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The shipping industry is going through a period of technology transition that aims to increase the use of carbon-neutral fuels. There is a significant trend of vessels being ordered with alternative fuel propulsion. Shipping’s future fuel market will be more diverse, reliant on multiple energy sources. One of very promising means to meet the decarbonisation requirements is to operate ships with sustainable electrical energy by integrating local renewables, shore connection systems and battery energy storage systems (BESS). With the increasing number of battery/hybrid propulsion vessels in operation and on order, this kind of vessel propulsion is becoming more common, especially in the segment of short range vessels. This paper presents review of recent studies of electrification or hybridisation, different aspects of using the marine BESS and classes of hybrid propulsion vessels. It also reviews several types of energy storage and battery management systems used for ships’ hybrid propulsion. The article describes different marine applications of BESS systems in relation to peak shaving, load levelling, spinning reserve and load response. The study also presents the very latest developments of hybrid/electric propulsion systems offered by leading maritime market manufacturers.

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11

RUIZ, LYDIA A., ROBERT W. WHITTLESEY y JOHN O. DABIRI. "Vortex-enhanced propulsion". Journal of Fluid Mechanics 668 (22 de diciembre de 2010): 5–32. http://dx.doi.org/10.1017/s0022112010004908.

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It has been previously suggested that the generation of coherent vortical structures in the near-wake of a self-propelled vehicle can improve its propulsive efficiency by manipulating the local pressure field and entrainment kinematics. This paper investigates these unsteady mechanisms analytically and in experiments. A self-propelled underwater vehicle is designed with the capability to operate using either steady-jet propulsion or a pulsed-jet mode that features the roll-up of large-scale vortex rings in the near-wake. The flow field is characterized by using a combination of planar laser-induced fluorescence, laser Doppler velocimetry and digital particle-image velocimetry. These tools enable measurement of vortex dynamics and entrainment during propulsion. The concept of vortex added-mass is used to deduce the local pressure field at the jet exit as a function of the shape and motion of the forming vortex rings. The propulsive efficiency of the vehicle is computed with the aid of towing experiments to quantify hydrodynamic drag. Finally, the overall vehicle efficiency is determined by monitoring the electrical power consumed by the vehicle in steady and unsteady propulsion modes. This measurement identifies conditions under which the power required to create flow unsteadiness is offset by the improved vehicle efficiency. The experiments demonstrate that substantial increases in propulsive efficiency, over 50 % greater than the performance of the steady-jet mode, can be achieved by using vortex formation to manipulate the near-wake properties. At higher vehicle speeds, the enhanced performance is sufficient to offset the energy cost of generating flow unsteadiness. An analytical model explains this enhanced performance in terms of the vortex added-mass and entrainment. The results suggest a potential mechanism to further enhance the performance of existing engineered propulsion systems. In addition, the analytical methods described here can be extended to examine more complex propulsion systems such as those of swimming and flying animals, for whom vortex formation is inevitable.

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12

SWALLOM, DANIEL W., ISAAC SADOVNIK, JUDY S. GIBBS, HUSAM GUROL, LONG V. NGUYEN y HUGO H. BERGH. "Magnetohydrodynamic Submarine Propulsion Systems". Naval Engineers Journal 103, n.º 3 (mayo de 1991): 141–57. http://dx.doi.org/10.1111/j.1559-3584.1991.tb00945.x.

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13

SWALLOM, DANIEL W., ISAAC SADOVNIK, JUDY S. GIBBS, HUSAM GUROL, LONG V. NGUYEN y HUGO H. BERGH. "MAGNETOHYDRODYNAMIC SUBMARINE PROPULSION SYSTEMS". Naval Engineers Journal 103, n.º 4 (julio de 1991): 120–23. http://dx.doi.org/10.1111/j.1559-3584.1991.tb01012.x.

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14

Fujisawa, Nobuyuki. "Measurements of Basic Performances for Waterjet Propulsion Systems in Water Tunnel". International Journal of Rotating Machinery 2, n.º 1 (1995): 43–50. http://dx.doi.org/10.1155/s1023621x95000194.

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Experimental techniques are described in detail for evaluating the system and the unit performances of waterjet propulsion systems in a water tunnel. The measured performances of pump and propulsion of the model systems are in reasonable agreement with the field experiment with prototype craft. Measurements are also made for the losses in the intake and the nozzle. The optimization study of the water jet systems is conducted by simulating the change of the nozzle outlet diameter with the variable nozzle arrangement. It is suggested that the nozzle outlet diameter should be decreased as the craft velocity increases to obtain an optimum propulsive efficiency in a wide range of craft velocity.

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15

Samoilescu, Gheorghe, Dumitru Iorgulescu, Robert Mitrea y Laura D. Cizer. "Propulsion Systems in Marine Navigation". International conference KNOWLEDGE-BASED ORGANIZATION 24, n.º 3 (1 de junio de 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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16

Figueiras, Iara, Maria Coutinho, Frederico Afonso y Afzal Suleman. "On the Study of Thermal-Propulsive Systems for Regional Aircraft". Aerospace 10, n.º 2 (24 de enero de 2023): 113. http://dx.doi.org/10.3390/aerospace10020113.

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Life without mobility is inconceivable. To enable this connectivity, one must find a way to progress towards a more sustainable transportation. In the aviation industry, a comprehensive understanding of greening technologies such as electrification of the propulsion system for commercial aircraft is required. A hybrid-electric propulsion concept applied to a regional aircraft is studied in the context of the FutPrInt50 project. To this end, the hybrid-electric propulsive system components are modeled, validated, and evaluated using computational and experimental data presented in the literature. The components are then assembled to construct the three powertrains for the hybrid-electric propulsion systems (Series, Parallel and Turboelectric) and parametric studies are carried out to study the influence of various battery parameters and hybridization factor. The performance results for a simple mission profile are generated. Together with a thermal management system, multi-objective optimization studies for the different architectures are then performed, with the power hybridization factor as the design variable and minimization of total mass and emissions as objective functions.

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17

Apsley, Judith M., Aurelio Gonzalez-Villasenor, Mike Barnes, Alexander C. Smith, Steve Williamson, Jeroen D. Schuddebeurs, Patrick J. Norman, Campbell D. Booth, Graeme M. Burt y J. R. McDonald. "Propulsion Drive Models for Full Electric Marine Propulsion Systems". IEEE Transactions on Industry Applications 45, n.º 2 (2009): 676–84. http://dx.doi.org/10.1109/tia.2009.2013569.

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18

Karthigan, Ganesan, Sujoy Mukherjee y Ranjan Ganguli. "Electromechanical dynamics and optimization of pectoral fin–based ionic polymer–metal composite underwater propulsor". Journal of Intelligent Material Systems and Structures 23, n.º 10 (6 de mayo de 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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Krmek, Ivica, Vedran Mrzljak y Igor Poljak. "Analysis and Comparison of Ship Propulsion Systems". Journal of Maritime & Transportation Science 62, n.º 1 (agosto de 2022): 75–95. http://dx.doi.org/10.18048/2022.62.05.

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One of the highest cost of building the ship refers to the ship’s propulsion system. It is therefore very important to know all the types and specificities of propulsion systems for the optimal selection. This paper presents the conventional and the combined propulsion systems, where are briefly given their characteristics and specificities. Special attention is given to the combined propulsion systems, whose extensive use is still under expectation. At the end, the paper discusses the cost calculation of a marine propulsion system of selected passenger cruiser and comparison to the possible alternative system.

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20

Rosato, Daniel A., Mason Thornton, Jonathan Sosa, Christian Bachman, Gabriel B. Goodwin y Kareem A. Ahmed. "Stabilized detonation for hypersonic propulsion". Proceedings of the National Academy of Sciences 118, n.º 20 (10 de mayo de 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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21

Zhang, Bowen, Zaixin Song, Fei Zhao y Chunhua Liu. "Overview of Propulsion Systems for Unmanned Aerial Vehicles". Energies 15, n.º 2 (10 de enero de 2022): 455. http://dx.doi.org/10.3390/en15020455.

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Unmanned Aerial Vehicle (UAV) propulsion technology is significantly related to the flight performance of UAVs, which has become one of the most important development directions of aviation. It should be noted that UAVs have three types of propulsion systems, namely the fuel, hybrid fuel-electric, and pure electric, respectively. This paper presents and discusses the classification, working principles, characteristics, and critical technologies of these three types of propulsion systems. It is helpful to establish the development framework of the UAV propulsion system and provide the essential information on electric propulsion UAVs. Additionally, future technologies and development, including the high-power density motors, converters, power supplies, are discussed for the electric propulsion UAVs. In the near future, the electric propulsion system would be widely used in UAVs. The high-power density system would become the development trend of electric UAVs. Thus, this review article provides comprehensive views and multiple comparisons of propulsion systems for UAVs.

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Savenko, A. E. y P. S. Savenko. "Features of operation of ship electrical power systems with electrical propulsion systems". Power engineering: research, equipment, technology 24, n.º 3 (14 de junio de 2022): 91–100. http://dx.doi.org/10.30724/1998-9903-2022-24-3-91-100.

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THE PURPOSE. Consider the issue of the presence of distortions in the form of sinusoidal voltage and current in autonomous electrical power systems with electrical propulsion systems, built on the principle of the unified electric power system. Compare the results of the study of voltage distortion for electrical power systems with electrical propulsion systems of various structures and give recommendations for their application.METHODS. For research, unified electric power systems with DC electrical propulsion systems on the Yeysk ferry and alternating current on the asymmetric icebreaker Baltika are considered. The possibilities of programming with frequency control of modern drives of rudder propellers with AC motors are analyzed.RESULTS. Oscillograms of voltages and currents of generators were obtained using thyristor converters and inverters to control electrical propulsion systems in various modes. Significant ripples and distortions of the sinusoidal voltage and generator currents were noted when thyristor converters are used to power DC propulsion electric motors. Also, small deviations from the sinusoidal form of the ship's network voltage were recorded when inverters were used to control AC propulsion motors as part of rudder propellers.CONCLUSION. The issue of ensuring the quality of electricity produced in autonomous electrical power systems of sea vessels is of great relevance and importance. To ensure the best results, it is advisable to use azimuthing podded drive with AC electric motors, the rotation speed of which is implemented by inverter frequency converters with a DC link.

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Mrzljak, Vedran y Tomislav Mrakovčić. "Comparison of COGES and Diesel-Electric Ship Propulsion Systems". Journal of Maritime & Transportation Science Special edition, n.º 1 (abril de 2016): 131–48. http://dx.doi.org/10.18048/2016-00.131.

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Diesel-electric ship propulsion is a frequent shipowners choice nowadays, especially on passengerships. Despite many diesel engines advantages, their primary disadvantage is emission of pollutants. As environmental standards become more stringent, the question of optimal alternative to diesel-electric propulsion arises. COGES (COmbined Gas turbine Electric and Steam) propulsion system is one of the proposals for alternative propulsion system, primarily due to significant reduction of pollutant emissions. On the other hand, gas turbines have higher specific fuel consumption in comparison with diesel engines what represents their noticeable disadvantage. However, some analyzes suggested that COGES propulsion system could be still cost-effective in comparison to diesel-electric propulsion, particularly on passenger ships where higher initial investment can be compensated by increasing the number of passenger cabins. This paper shows a comparison of above mentioned propulsion systems, which can be useful for the optimal ship propulsion system selection

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Gemmell, Brad J., Sean P. Colin, John H. Costello y Kelly R. Sutherland. "A ctenophore (comb jelly) employs vortex rebound dynamics and outperforms other gelatinous swimmers". Royal Society Open Science 6, n.º 3 (marzo de 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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Li, Qiao, Shahrir Abdullah y Mohammad Rasidi Mohammad Rasani. "A Review of Progress and Hydrodynamic Design of Integrated Motor Pump-Jet Propulsion". Applied Sciences 12, n.º 8 (10 de abril de 2022): 3824. http://dx.doi.org/10.3390/app12083824.

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The integrated motor pump-jet (IMP) propulsion system is a form of modern underwater vehicle propulsion that uses a modular design paradigm. The integrated motor propulsor is a compact construction consisting of a permanent magnet (PM) and a pump-jet propulsor, as well as the propulsion and electrical systems. Compactness, great reliability, and low noise are the most significant features of this technology. The primary technology research status and main application configurations of propulsion devices with an integrated motor were examined based on the working principles and attributes of the devices. The theoretical and experimental research on the design, performance analysis, and control of IMPs is discussed, covering electric motors; bearing structures; hydrodynamic design; and hydrodynamic, electromagnetic, and bearing coupling design technology. This research investigates the most recent research goals, progress, and applications of IMPs, which includes their hydrodynamic performance, cavitation, and gap flow. Finally, the future essential technologies of high power, low vibration, water-lubricated bearings, electromagnetic and bearing coupling design, and IMP antipollution and antidamage capacity are summarized.

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Duan, Zheng, Yajie Chen, Haibo Gao y Linhao Liao. "Analysis of Key Technologies for New Green Marine Propulsion Systems". E3S Web of Conferences 194 (2020): 02008. http://dx.doi.org/10.1051/e3sconf/202019402008.

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The new green Marine propulsion system, as a new generation of marine propulsion, has advantages of strong mobility, low fuel consumption, low noise, safety and comfort. Three green propulsion solutions for different ship types are proposed, including pure electric propulsion system, compound energy storage electric propulsion system and diesel-electric hybrid propulsion system. The structure features and performance advantages are introduced and the key technologies such as new energy storage, DC network and shaft generator/motor are discussed. The related research achievements and typical project cases are also introduced.

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Adeola Ona-Olapo Esho, Tosin Daniel Iluyomade, Tosin Michael Olatunde y Osayi Philip Igbinenikaro. "Electrical propulsion systems for satellites: a review of current technologies and future prospects". International Journal of Frontiers in Engineering and Technology Research 6, n.º 2 (30 de abril de 2024): 035–44. http://dx.doi.org/10.53294/ijfetr.2024.6.2.0034.

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Electrical propulsion systems have revolutionized satellite technology by offering greater efficiency, longer mission durations, and increased maneuverability compared to traditional chemical propulsion systems. This review explores current technologies and future prospects in the field of electrical propulsion systems for satellites. The discussion begins with an overview of existing technologies, including ion propulsion systems, Hall effect thrusters, and pulsed plasma thrusters. Each technology's principles of operation, advantages, limitations, and notable applications are examined. The review delves into the future prospects of electrical propulsion systems, exploring advanced concepts such as magnetoplasmadynamic thrusters, variable specific impulse magnetoplasma rockets, and electrospray propulsion systems. Additionally, miniaturization and efficiency improvements, as well as sustainable and green propulsion alternatives, are discussed. Challenges and opportunities facing the field are addressed, including technical hurdles like power generation and management, thruster lifespan, and regulatory and economic considerations such as policy frameworks and market dynamics. In conclusion, the review underscores the critical role of continued research and development in electrical propulsion systems for satellites. As the demand for more capable and sustainable satellite missions grows, advancements in propulsion technology will be essential in meeting these evolving needs and pushing the boundaries of space exploration.

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28

Tripathy, Poonam. "Overview On Electric Propulsion Systems". International Journal of Scientific and Research Publications (IJSRP) 10, n.º 12 (12 de diciembre de 2020): 422–39. http://dx.doi.org/10.29322/ijsrp.10.12.2020.p10846.

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29

Vega, Emanuel Pablo, Olivier Chocron y Mohamed El Hachemi Benbouzid. "AUV Propulsion Systems Modeling Analysis". International Review on Modelling and Simulations (IREMOS) 7, n.º 5 (31 de octubre de 2014): 827. http://dx.doi.org/10.15866/iremos.v7i5.3648.

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30

Chakravarthy, B. K. "Hybrid Diesel-Electric Propulsion Systems". CVR Journal of Science & Technology 10, n.º 1 (1 de junio de 2016): 65–69. http://dx.doi.org/10.32377/cvrjst1014.

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31

Dimitrova, Zlatina. "Vehicle propulsion systems design methods". MATEC Web of Conferences 133 (2017): 02001. http://dx.doi.org/10.1051/matecconf/201713302001.

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32

Gao, Ximing y Janice Houston. "Acoustics research of propulsion systems". Journal of the Acoustical Society of America 136, n.º 4 (octubre de 2014): 2136. http://dx.doi.org/10.1121/1.4899705.

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33

Evvard, John C. "PERSPECTIVE ON AEROSPACE PROPULSION SYSTEMS". Annals of the New York Academy of Sciences 134, n.º 1 (26 de febrero de 2008): 342–54. http://dx.doi.org/10.1111/j.1749-6632.1965.tb56165.x.

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34

MIYAJIMA, Hiroshi. "Liquid propulsion systems for satellites." Journal of the Japan Society for Aeronautical and Space Sciences 33, n.º 373 (1985): 52–58. http://dx.doi.org/10.2322/jjsass1969.33.52.

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35

Stuhlinger, Ernst. "Future Deep Space Propulsion Systems". International Astronomical Union Colloquium 123 (1990): 355–62. http://dx.doi.org/10.1017/s0252921100077289.

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AbstractAmong several potential future deep space propulsion systems, the two which are closest to realization are selected for closer consideration: solar-electric, and nuclear-electric propulsion. In particular, the paper describes a manned Mars mission using a particle bed reactor and Brayton cycle converter as power source. Technical details of the design and the mission profile of a 4-astronaut expedition to Mars, and a proposed course of action for project implementation are presented.

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36

Timnat, Y. M. "Diagnostic techniques for propulsion systems". Progress in Aerospace Sciences 26, n.º 2 (enero de 1989): 153–68. http://dx.doi.org/10.1016/0376-0421(89)90007-9.

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37

Yang, Vigor. "Combustion instabilities in propulsion systems". Journal of the Acoustical Society of America 107, n.º 5 (mayo de 2000): 2816. http://dx.doi.org/10.1121/1.429082.

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38

Bishop, Forrest. "Some novel space propulsion systems". Aircraft Engineering and Aerospace Technology 75, n.º 3 (junio de 2003): 247–55. http://dx.doi.org/10.1108/00022660310474474.

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39

Gagarinov, I. "Structures of high-power electric propulsion systems". Transactions of the Krylov State Research Centre 1, n.º 395 (9 de marzo de 2021): 119–31. http://dx.doi.org/10.24937/2542-2324-2021-1-395-119-131.

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Object and purpose of research. This paper discusses structures of high-power electric propulsion systems for ships. The purpose was to give a summary of design solutions made in development of these systems. Materials and methods. This paper relies on academic and technical data, as well on the long-term author’s experience in marine electric propulsion R&Ds. The solution suggested by the author is based on the comparative analysis of design solutions adopted in the development of structures for high-power marine electric power and propulsion systems. Main results. Summary on design solutions for high-power electric propulsion systems of such ships as icebreakers, oil tankers, LNGCs and cruise liners. Conclusion. Results obtained by author were used in the design of the electric propulsion system of the «Lider» nuclear icebreaker and further could be used in design of Arctic vessels.

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40

Kondryakov, A. D. y M. K. Leontiev. "Aircraft electric power plants". VESTNIK of Samara University. Aerospace and Mechanical Engineering 23, n.º 2 (10 de julio de 2024): 49–61. http://dx.doi.org/10.18287/2541-7533-2024-23-2-49-61.

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The paper presents a review of electrification of the existing propulsion systems and creating new hybrid propulsion systems based on the concept of more electric aircraft and all-electric aircraft in Russia and abroad. New promising directions of electrification of the existing aircraft propulsion systems and creating new hybrid aircraft propulsion systems are specified on the basis of the review.

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41

Erriah, Joylan Rao, Pengfei Liu y Serkan Turkmen. "Hydrodynamic Development and Optimisation of a Retrofittable Dual-Mode Propeller Turbine". Energies 17, n.º 13 (26 de junio de 2024): 3138. http://dx.doi.org/10.3390/en17133138.

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Dual-mode propellers, as propulsion and turbine devices, have found widespread application in renewable energy systems for marine vehicles, particularly in sailing boats and yachts. However, the existing dual-mode propellers in these contexts are typically chosen in an off-the-shelf manner, indicating a lack of hydrodynamic optimisation to enhance both the propulsion and energy generation efficiency in the same rotor. To address this limitation and furnish scientific validation of the design of a dual-mode propeller turbine rotor optimised to achieve a balanced performance in both propulsion and energy generation, rigorous experimentation was conducted using specialised software, Rotorysics 2019, and a case study vessel, the Princess Royale. Utilising prior experimental data for this propeller turbine, code validation was undertaken to ensure accurate prediction of the effects of the pitch, blade count and expanded area ratio on the performance in both modes. With the intention of achieving optimal power generation and propulsion efficiencies in conjunction with a single rotor, the findings reveal that the optimised fixed-pitch propeller exhibits dual functionality. They serve as both propulsion and tidal/current turbines with balanced efficiency. They are particularly suitable for low-speed vessels such as yachts anchored in currents or for sailboats utilising a propeller as a towed turbine. Through thorough testing and analysis, the concept of a dual-mode propeller turbine was feasible. Analysing them separately, in terms of the propulsion, the best geometry found through numerous tests of different expanded area ratios, blade number, pitch and speed was the 3-blade, 0.6 pitch ratio, which achieved a propulsive efficiency of 54.33% (0.5433204) and a power coefficient of 0.291843. Conversely, if the focus was on power generation while maintaining excellent propulsive efficiency, the optimal geometry would be the 5-blade, 0.6 pitch ratio, which offers a power coefficient of 0.348402 and a propulsive efficiency of 48.55% (0.48547). However, when using both power generation and propulsion as the criteria, the 5-blade, 0.6 pitch ratio, with an EAR of 0.387142, is superior, with balanced optimisation, offering a propulsive efficiency of 52.53% (0.52527) and a power coefficient of 0.319718. As expected, this encompasses a higher blade number for increased power generation efficiency and a higher pitch ratio for increased propulsive efficiency.

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42

Kato, Naomi. "Median and Paired Fin Controllers for Biomimetic Marine Vehicles". Applied Mechanics Reviews 58, n.º 4 (1 de julio de 2005): 238–52. http://dx.doi.org/10.1115/1.1946027.

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This paper reviews the studies on the kinematics, hydrodynamics, and performance of median and paired fin (MPF) in fish and biomimetic mechanical systems from the viewpoint of enhancing the propulsive and maneuvering performance of marine vehicles at low speeds. Precise maneuverability and stability at low swimming speeds by use of MPF propulsion seem to be advantageous in complex habitats such as coral reefs. MPF propulsion in fish consists of undulatory fin motion and oscillatory fin motion. The kinematics of MPF in fish and mechanical systems in both groups is discussed. Hydrodynamic models and experimental data of undulatory and oscillatory motions of MPF in fish and mechanical system are reviewed. Pectoral fin propulsion has two categories which represent biomechanical extremes in the use of appendages for propulsion: drag-based and lift-based mechanisms of thrust production. The hydrodynamic characteristics of the two mechanisms are compared. The performance of fish and vehicles with MPF is reviewed from the viewpoint of maneuverability. Especially, performance of a recently developed fish-like body with a pair of undulatory side fins, a model ship with a pair of ray-wing-type propulsors, and an underwater vehicle with two pairs of mechanical pectoral fins are discussed.

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43

Reisz, Aloysius I. "To Go Beyond". Mechanical Engineering 130, n.º 11 (1 de noviembre de 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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44

Nadar, Ryan. "Innovations in Laser-Driven Plasma Propulsion Systems for Space Exploration". Acceleron Aerospace Journal 1, n.º 5 (30 de diciembre de 2023): 101–3. http://dx.doi.org/10.61359/11.2106-2321.

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Laser propulsion has emerged as a promising technology for revolutionizing space exploration by offering rapid and efficient spacecraft propulsion. This paper proposes a novel system that integrates dense corona discharge with electrical mechanisms to significantly enhance the efficiency and effectiveness of laser propulsion. Leveraging plasma physics and laser technology, this system harnesses the synergy between dense plasma and laser-driven propulsion, significantly exceeding the capabilities of conventional systems. Theoretical analysis and computational simulations reveal the potential for increased thrust, improved energy conversion efficiency, and enhanced controllability, paving the way for next-generation spacecraft propulsion technologies.

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45

Levchenko, Igor, Oleg Baranov, Daniela Pedrini, Claudia Riccardi, H. Eduardo Roman, Shuyan Xu, Dan Lev y Kateryna Bazaka. "Diversity of Physical Processes: Challenges and Opportunities for Space Electric Propulsion". Applied Sciences 12, n.º 21 (3 de noviembre de 2022): 11143. http://dx.doi.org/10.3390/app122111143.

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The renewed interest in space exploration has led to the growth in research efforts pertaining to advanced space propulsion systems, including highly efficient electric propulsion systems. Although already tested in space many decades ago and being currently employed on various space platforms and thousands of satellites, these systems are yet to reach their full potential for applications on orbit and in deep space. One specific feature of space electric propulsion is the large diversity of physical processes used in this technology, which is not typical for many other types of propulsion systems used in transport, such as those used by airplanes or automobiles. Various physical processes and mechanisms underpin different electric propulsion technologies and should be integrated to drive the future science and technology of space electric propulsion systems. This opinion article briefly highlights this feature of space electric propulsion and outlines some challenges and opportunities that follow from this diversity.

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46

Jang, Junseop. "A Study on the Submarine Air Independent Propulsion System: Focused on Submarines Currently in Operation". Journal of the Korea Institute of Military Science and Technology 24, n.º 4 (5 de agosto de 2021): 418–25. http://dx.doi.org/10.9766/kimst.2021.24.4.418.

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Submarines are weapons systems that have been proven to be useful in battle since World War I and have continued to improve the efficiency of propulsion systems in order to be used efficiently on the battlefield. In particular, countries that unable to utilize nuclear propulsion systems make efforts to increase the efficiency of Air Independent Propulsion systems, and typical examples are fuel cells, Stirling engines and MESMA. It is also expected that the development of new propulsion systems such as hydrogen-reformer fuel cells, metal-air fuel cell and direct combustion propulsion systems will continue, so the characteristics of these will be examined and the performance based on the published data be checked in this thesis.

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47

Piwowarski, Marian. "The Analysis of Turbine Propulsion Systems in Nuclear Submarines". Key Engineering Materials 597 (diciembre de 2013): 99–105. http://dx.doi.org/10.4028/www.scientific.net/kem.597.99.

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The article systematises submarines, which are presently in service, according to their propulsion types (both conventional and nuclear), power output, and submersion depth. Contemporary types of propulsion systems installed and used in submarines are discussed. Calculations were performed for the PWR type nuclear propulsion system and the supercritical turbine propulsion system (supercritical reactor cooled with light water). Preliminary designs of turbines have been worked out for these two variants, and the systems were compared with respect to cycle efficiency and turboset efficiency.

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48

Alulema, Victor, Esteban Valencia, Edgar Cando, Victor Hidalgo y Dario Rodriguez. "Propulsion Sizing Correlations for Electrical and Fuel Powered Unmanned Aerial Vehicles". Aerospace 8, n.º 7 (24 de junio de 2021): 171. http://dx.doi.org/10.3390/aerospace8070171.

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Despite the increasing demand of Unmanned Aerial Vehicles (UAVs) for a wide range of civil applications, there are few methodologies for their initial sizing. Nowadays, classical methods, mainly developed for transport aircraft, have been adapted to UAVs. However, these tools are not always suitable because they do not fully adapt to the plethora of geometrical and propulsive configurations that the UAV sector represents. Therefore, this work provides series of correlations based on off-the-shelf components for the preliminary sizing of propulsion systems for UAVs. This study encompassed electric and fuel-powered propulsion systems, considering that they are the most used in the UAV industry and are the basis of novel architectures such as hybrid propulsion. For these systems, weight correlations were derived, and, depending on data availability, correlations regarding their geometry and energy consumption are also provided. Furthermore, a flowchart for the implementation of the correlations in the UAV design procedure and two practical examples are provided to highlight their usability. To summarize, the main contribution of this work is to provide parametric tools to size rapidly the propulsion system components, which can be embedded in a UAV design and optimization framework. This research complements other correlation studies for UAVs, where the initial sizing of the vehicle is discussed. The present correlations suit multiple UAV categories ranging from micro to Medium-Altitude-Long-Endurance (MALE) UAVs.

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49

Dahms, Julius y Andreas Bardenhagen. "Propulsion model for (hybrid) unmanned aircraft systems (UAS)". Aircraft Engineering and Aerospace Technology 91, n.º 2 (4 de febrero de 2019): 373–80. http://dx.doi.org/10.1108/aeat-01-2018-0033.

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Purpose This paper deals with the estimation of the necessary masses of propulsion components for multirotor UAS. Originally, within the design process of multirotors, this is an iterative problem, as the propulsion masses contribute to the total takeoff mass. Hence, they influence themselves and cannot be directly calculated. The paper aims to estimate the needed propulsion masses with respect to the requested thrust because of payload, airframe weight and drag forces and with respect to the requested flight time. Design/methodology/approach Analogue to the well-established design synthesis of airplanes, statistical data of existing electrical motors, propellers and rechargeable batteries are evaluated and analyzed. Applying Rankine and Froude’s momentum theory and a generic model for electro motor efficiency factors on the statistical performance data provides correlations between requested performance and, therefore, needed propulsion masses. These correlations are evaluated and analyzed in the scope of buoyant-vertical-thrusted hybrid UAS. Findings This paper provides a generic mathematical propulsion model. For given payloads, airframe structure weights and a requested flight time, appropriate motor, propeller and battery masses can be modelled that will provide appropriate thrust to lift payload, airframe and the propulsion unit itself over a requested flight time. Research limitations/implications The model takes into account a number of motors of four and is valid for the category of nano and small UAS. Practical implications The presented propulsion model enables a full numerical design process for vertical thrusted UAS. Hence, it is the precondition for design optimization and more efficient UAS. Originality/value The propulsion model is unique and it is valid for pure multirotor as well as for hybrid UAS too.

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50

Large, James y Apostolos Pesyridis. "Investigation of Micro Gas Turbine Systems for High Speed Long Loiter Tactical Unmanned Air Systems". Aerospace 6, n.º 5 (14 de mayo de 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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