Journal articles: 'Water jets Underwater propulsion'

1

Tang, Jia-Ning, Ning-Fei Wang, and Wei Shyy. "Flow structures of gaseous jets injected into water for underwater propulsion." Acta Mechanica Sinica 27, no. 4 (July 11, 2011): 461–72. http://dx.doi.org/10.1007/s10409-011-0474-4.

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Song, Zhuoyuan, Cameron Mazzola, Eric Schwartz, Ruirong Chen, Julian Finlaw, Mike Krieg, and Kamran Mohseni. "A Compact Autonomous Underwater Vehicle With Cephalopod-Inspired Propulsion." Marine Technology Society Journal 50, no. 5 (September 1, 2016): 88–101. http://dx.doi.org/10.4031/mtsj.50.5.9.

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AbstractIn this paper, a bioinspired, compact, cost-effective autonomous underwater vehicle system is presented. Designed to operate in a heterogeneous, multivehicle collaboration hierarchy, the presented vehicle design features 3D printing technology to enable fast fabrication with a complex internal structure. Similar to a previous vehicle prototype, this system generates propulsive forces by expelling unsteady, pulsed jets, inspired by the locomotion of cephalopods and jellyfish. The novel thrusters enable the vehicle to be fully actuated in horizontal plane motions, without sacrificing the low-forward-drag, slender vehicle profile. By successively ingesting water and expelling finite water jets, periodic actuation forces are generated at all possible vehicle velocities, eliminating the need for control surfaces used in many conventional underwater vehicle designs. A semiactive buoyancy control system, inspired by the nautilus, adjusts the vehicle depth by passively allowing water flowing into and actively expelling water out of an internal bladder. A compact embedded system is developed to achieve the control and sensing capabilities necessary for multiagent interactions with the minimum required processing power and at a low energy cost. The new vehicle design also showcases an underwater optical communication system for short-range, high-speed data transmission, supplementing the conventional acoustic communication system. Experimental results show that, with the thruster motors powered at a 60% duty-cycle, the new vehicle is able to achieve a 1/4 zero-radius turn in 3.5 s and one-body-width sway translation in 2.5 s.

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Krieg, Michael, Peter Klein, Robert Hodgkinson, and Kamran Mohseni. "A Hybrid Class Underwater Vehicle: Bioinspired Propulsion, Embedded System, and Acoustic Communication and Localization System." Marine Technology Society Journal 45, no. 4 (July 1, 2011): 153–64. http://dx.doi.org/10.4031/mtsj.45.4.11.

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AbstractInspired by the natural locomotion of jellyfish and squid, a series of compact thrusters series is developed for propulsion and maneuvering of underwater vehicles. These thrusters successively ingest and expel jets of water in a controlled manner at high frequencies to generate propulsive forces. The parameters controlling the performance of the thrusters are reviewed and investigated to achieve higher thrust levels. The thrusters are compact and can be placed completely inside a vehicle hull providing the desired maneuvering capability without sacrificing a sleek hydrodynamic shape for efficient cruising. The system design of a prototype hybrid vehicle, called CephaloBot, utilizing these thrusters, is also presented. A compact and custom-developed embedded system is also designed for the CephaloBot. Key features of the system include a base set of navigational sensors, an acoustic system for localization and underwater communication, Xbee RF transceiver for communication above water, and a LabVIEW programmed processing board.

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Shaari, Muhammad Farid, Samad Zahurin, Mohd Elmi Abu Bakar, and M. Mariatti. "Design Consideration of Bio-Inspired Contractible Water-Jet Propulsor for Mini Autonomous Underwater Robot." Advanced Materials Research 463-464 (February 2012): 1583–88. http://dx.doi.org/10.4028/www.scientific.net/amr.463-464.1583.

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The main aim of this paper is to discuss the general design considerations for contractible water-jet propulsion system for mini underwater robot locomotion. The motivation of this paper is the problems that occurred to the motorized turbine blade propeller for a lower than centimeter scale underwater robot. Contractile water-jet propulsion mechanism is proposed to counter the turbine blade problem. In this research, active materials had been proposed as the actuator for the contractile function. The integration of active material structure and passive structure caused significant consequence on the kinematic and dynamic of the robot. This including the dimension variation, stress distribution as well as contraction force which affects the hydrodynamic efficiency of the propulsion. Several essential design considerations were highlighted and discussed.

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Mo, Jixue, Zhihuai Miao, Bing Li, Yunlu Zhang, and Zhendong Song. "Design, analysis, and performance verification of a water jet thruster for amphibious jumping robot." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, no. 15 (April 26, 2019): 5431–47. http://dx.doi.org/10.1177/0954406219844529.

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In nature, certain aquatic animals and seabirds are capable of leaping from water surface and overcoming aquatic obstacles with ease. Inspired by that, researchers have developed various underwater robots, which can perform the aquatic jumping motion. Although there are several ways to achieve it, the water jet propulsion is the most appropriate approach for the amphibious jumping robot, which is under development. In this paper, a high-performance water jet thruster powered by liquid nitrogen is proposed to be the potential actuator for the amphibious jumping robot. The theoretical jumping model is built to optimize the initial volume fraction of water inside thruster and analyze its parameters' variation during water jet. Then the computational fluid dynamics simulations by ANSYS FLUENT software are carried out to analyze the self-pressurization process of liquid nitrogen as well as the water jet process. Finally, the proof-of-concept outdoor experiments present that the 3.7 kg thruster's maximum aquatic and terrestrial jumping heights are 25.1 m and 24.4 m, respectively. A simple heat transfer analysis between water and liquid nitrogen is also conducted, and the order of magnitude estimation of heat transfer coefficient is given to be 265W/ (m2·K) based on the experimental reaction time.

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Han, Zhao Lin, and De Long Chen. "The Kinematic Analysis of Double Water Jets Ship." Applied Mechanics and Materials 723 (January 2015): 167–70. http://dx.doi.org/10.4028/www.scientific.net/amm.723.167.

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This document explains hydrodynamic force of water jet propulsion and kinematic characteristics of double water jets ship. Firstly, study on the water jet thrust based on the theorem of momentum. Then discuss the hydrodynamic performance of the water jet reversing bucket, calculate the backing force produced in the condition of different flow rate and nozzle angle. On the basis of hydrodynamic analysis of water jet, we next explore the various motion modes of double water jet propulsion ship, especially kinematic analysis of ship’s in-situ rotary movement and transverse movement.

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Moon, Heejang, Seongjoo Han, Youngjun You, and Minchan Kwon. "Hybrid Rocket Underwater Propulsion: A Preliminary Assessment." Aerospace 6, no. 3 (March 6, 2019): 28. http://dx.doi.org/10.3390/aerospace6030028.

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This paper presents an attempt to use the hybrid rocket for marine applications with a 500 N class hybrid motor. A 5-port high density polyethylene (HDPE) fuel grain was used as a test-bed for the preliminary assessment of the underwater boosting device. A rupture disc preset to burst at a given pressure was attached to the nozzle exit to prevent water intrusion where a careful hot-firing sequence was unconditionally required to avoid the wet environment within the chamber. The average thrust level around 450 N was delivered by both a ground test and an underwater test using a water-proof load cell. However, it was found that instantaneous underwater thrusts were prone to vibration, which was due in part to the wake structure downstream of the nozzle exit. Distinctive ignition curves depending on the rupture disc bursting pressure and oxidizer mass flow rate were also investigated. To assess the soft-start capability of the hybrid motor, the minimum power thrust, viewed as the idle test case, was evaluated by modulating the flow controlling valve. It was found that an optimum valve angle, delivering 16.3% of the full throttle test case, sustained the minimum thrust level. This preliminary study suggests that the throttable hybrid propulsion system can be a justifiable candidate for a short-duration, high-speed marine boosting system as an alternative to the solid underwater propulsion system.

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Xin, Ba, Luo Xiaohui, Shi Zhaocun, and Zhu Yuquan. "A vectored water jet propulsion method for autonomous underwater vehicles." Ocean Engineering 74 (December 2013): 133–40. http://dx.doi.org/10.1016/j.oceaneng.2013.10.003.

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SUZUKI, Akihiro, Masahiro OSAKABE, and Hayato KONDO. "Propulsion System of Underwater Vehicle with Low Speed Water Jet." Proceedings of the National Symposium on Power and Energy Systems 2016.21 (2016): A113. http://dx.doi.org/10.1299/jsmepes.2016.21.a113.

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Lu, Yeming, Haoran Liu, Xiaofang Wang, and Hui Wang. "Study of the Operating Characteristics for the High-Speed Water Jet Pump Installed on the Underwater Vehicle with Different Cruising Speeds." Journal of Marine Science and Engineering 9, no. 3 (March 22, 2021): 346. http://dx.doi.org/10.3390/jmse9030346.

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Due to the higher propulsive efficiency, lesser vibration, and better maneuverability, the water jet pump is widely applied to high-speed underwater vehicles. By taking a newly developed water jet pump system as the object, the corresponding underwater vehicle’s operating characteristics affected by different cruising speeds (15.43, 30.86, and 52.47 m/s) were investigated. The steady results reply that the cruising speed increase will result in the decline of the overall performances comprised of the head, the efficiency, the thrust, and the power. While, by using different analyzing methods, the unsteady results are listed as follows: (1) The energy loss theory denotes that the increasing cruising speed promoted the kinetic energy diffusion from the Reynolds stress and viscous stress and depress the turbulent kinetic energy production and the viscous dissipation. (2) The statistical PLS method reveals that the tip load effect on the leakage flow becomes weaker when the cruising speed becomes larger, while the effect from the scraping pressure has a completely opposite trend. (3) Further unsteady analysis implies that the increasing cruising speed makes the pressure pulsation larger and makes the radial force, the axial force, and the cloudy cavity size smaller.

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Zhang Xiao-Shi, Xu Hao, Wang Cong, Lu Hong-Zhi, and Zhao Jing. "Experimental study on underwater supersonic gas jets in water flow." Acta Physica Sinica 66, no. 5 (2017): 054702. http://dx.doi.org/10.7498/aps.66.054702.

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12

Yusof, Ahmad Anas, Faizil Wasbari, and Mohd Qadafie Ibrahim. "Research Development of Energy Efficient Water Hydraulics Manipulator for Underwater Application." Applied Mechanics and Materials 393 (September 2013): 723–28. http://dx.doi.org/10.4028/www.scientific.net/amm.393.723.

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This paper presents research development of water hydraulicsmanipulator testrig for underwater application at Centre for AdvancedResearch on Energy, Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka. The test rig is designed in order to study the effectiveness of using water hydraulics system for underwater manipulation application. With objectives to promote sustainability and energy saving, the manipulator system is targeted for usage in an underwater scenario, possibly on small submarines or underwater remotely operated vehicles (ROVs).Underwater vehicles normally utilize the use of oil hydraulics for propulsion, manipulation and instrument control. The research on underwater manipulator that uses the surrounding sea water itself as the power and energy carrier for control is now possible with the current development in water hydraulics technology.

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Zhang, Xiaoyuan, Shipeng Li, Baoyu Yang, and Ningfei Wang. "Flow structures of over-expanded supersonic gaseous jets for deep-water propulsion." Ocean Engineering 213 (October 2020): 107611. http://dx.doi.org/10.1016/j.oceaneng.2020.107611.

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Zhang, Naiqing, Yue Wen, and James Friend. "MHz-Order Surface Acoustic Wave Thruster for Underwater Silent Propulsion." Micromachines 11, no. 4 (April 16, 2020): 419. http://dx.doi.org/10.3390/mi11040419.

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High frequency (MHz-order) surface acoustic waves (SAW) are able to generate intense fluid flow from the attenuation of acoustic radiation in viscous fluids as acoustic streaming. Though such flows are known to produce a force upon the fluid and an equivalent and opposing force upon the object producing the acoustic radiation, there is no convenient method for measuring this force. We describe a new method to accomplish this aim, noting the potential of these devices in providing essentially silent underwater propulsion by virtue of their use of the sound itself to generate fluid momentum flux. Our example employs a 40 MHz SAW device as a pendulum bob while immersed in a fluid, measuring a 1.5 mN propulsion force from an input power of 5 W power to the SAW device. Supporting details regarding the acoustic streaming profile via particle image velocimetry and an associated theoretical model are provided to aid in the determination of the propulsion force knowing the applied power and fluid characteristics. Finally, a simple model is provided to aid the selection of the acoustic device size to maximize the propulsion force per unit device area, a key figure of merit in underwater propulsion devices. Using this model, a maximum force of approximately 10 mN/cm 2 was obtained from 1 W input power using 40 MHz SAW in water and producing a power efficiency of approximately 50%. Given the advantages of this technology in silent propulsion with such large efficiency and propulsion force per unit volume, it seems likely this method will be beneficial in propelling small autonomous submersibles.

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Kolaini, Ali R., Ronald A. Roy, Lawrence A. Crum, and Yi Mao. "Low‐frequency underwater sound generation by impacting transient cylindrical water jets." Journal of the Acoustical Society of America 94, no. 5 (November 1993): 2809–20. http://dx.doi.org/10.1121/1.407373.

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Luo, Xiaohui, Qiuping Li, Zuti Zhang, and Jijian Zhang. "Research on the underwater noise radiation of high pressure water jet propulsion." Ocean Engineering 219 (January 2021): 108438. http://dx.doi.org/10.1016/j.oceaneng.2020.108438.

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CHILDRESS, STEPHEN. "Walking on water." Journal of Fluid Mechanics 644 (February 10, 2010): 1–4. http://dx.doi.org/10.1017/s0022112009993107.

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Many insects and spiders can travel on the water surface by rapid synchronized movements of the legs. It has been found that frictional forces, capillary waves and the creation of water jets and eddies beneath the fluid surface are all involved in the mechanisms of propulsion used by these creatures. Elaborate adaptations of the body structure mediate the wetting and de-wetting of the body surface to provide support and differential adhesion. Flow visualization as well as theoretical modelling have led to an understanding of the mechanisms invoked by water striders and spiders for water walking with a variety of gaits and speeds.

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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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Li, Hua Feng, Xiao Feng Wang, Xia Ming Kong, and Xing Sheng Lao. "Thermal Management System Analysis of Underwater Vehicle Fuel Cell Propulsion Unit." Advanced Materials Research 779-780 (September 2013): 857–60. http://dx.doi.org/10.4028/www.scientific.net/amr.779-780.857.

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A lumped parameter model is developed to study thermal management system performance of underwater vehicle equipping large power proton exchange membrane fuel cell propulsion unit. Fuel cell voltage current characteristic and heat release characteristic are represented by models which take effect of cooling water temperature into considered. Fuel cell stack performance models are validated against experimental data. Cooperated with experimental based models of water pump and heat exchanger, thermal management system performance is analyzed while fuel cell stack fresh cooling water outlet temperature is set to be at a certain value. The results show that inlet seawater temperature variation has little effect on opening of regulating valve, but engine power output variation results in notably regulating valve opening fluctuation. Modeling results would be employed in design of a underwater vehicle 300kW fuel cell engine system..

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Mei, Lei, Junwei Zhou, Dong Yu Weichao Shi, Xiaoyun Pan, and Mingyang Li. "Parametric Analysis for Underwater Flapping Foil Propulsor." Water 13, no. 15 (July 31, 2021): 2103. http://dx.doi.org/10.3390/w13152103.

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This paper researched into the harmonic and anharmonic underwater flapping foil propulsion systems to improve the efficiency of these bioinspired propulsors. The angle of attack, the pitching angle, the heaving amplitude, and the phase difference are parametrically investigated in this paper. A rigid two-dimensional NACA (National Advisory Committee for Aeronautics) 0012 airfoil is modeled with the aid of a commercial computational fluid dynamics software, FINE™/Marine. Unsteady Reynolds Average Navier-Stokes (URANS) equation is solved together with dynamic mesh to simulate the foil motion. The investigation first verifies the reliability of the developed modeling method against the benchmark data. Then, the systematic investigation is conducted and identifies that the heaving amplitude is most influential factor for the propulsion efficiency. Secondly, phase difference also has a significant influence on efficiency, but this effect is related to the reference working condition, which needs further study. Then, the pitching amplitude has little effect on the maximum efficiency value of flapping foil, while it will affect its optimal speed range. When the heaving amplitude ratio reaches 3 and the corresponding maximum angle of attack is about 9°, the maximum efficiency can reach 87%. The effect of anharmonic motion on the efficiency is very small and varies with the St number, but in summary, it can maintain the peak efficiency over a wider range of operations. In addition, the force and flow field characteristics of different efficiency points are compared and analyzed to distinguish their corresponding relationship with the propulsion efficiency.

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Hong, Sung-Min, Sinje Lee, Jong-Wu Hyeon, Jung-Han Lee, Seunghun Lee, Cheolku Lee, and Sung-Hyub Ko. "Optimal design of combined propulsion Underwater Glider for operation of the East Sea of South Korea." Advances in Mechanical Engineering 11, no. 6 (June 2019): 168781401985648. http://dx.doi.org/10.1177/1687814019856482.

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An underwater glider is an autonomous underwater vehicle that is propelled by changes in volume. Due to this propulsion method, it is possible to make observations with these devices continuously for 30–60 days. Of the gliders’ physical properties, the volume change has the greatest influence on the cruising speed. The speed can be increased by increasing the volume change, but this also increases the energy consumption. Therefore, the change in buoyancy is very important for the operation of underwater gliders. Hence, it is necessary to optimize the change in buoyancy. In this study, we describe a technique for optimizing the design of underwater gliders intended to operate in the East Sea of Korea using a combined buoyancy engine and thruster propulsion system. First, we carried out a simulation study to optimize the volume change of the buoyancy engine based on the average flow velocity distribution, water temperature, and vertical salinity distribution in the East Sea. Then, we used our simulations to predict the optimal change in volume of the underwater glider. Finally, we discuss the advantages of operating with thrusters in special environments under specific water temperature, salinity distribution, and ocean current conditions.

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Donyavizadeh, Negin, and Parviz Ghadimi. "Efficacy Analysis of Thickness and Camber Size of Cross Section of the Stator on Hydrodynamic Parameters in Linear Jet Propulsion System." Mathematical Problems in Engineering 2020 (August 12, 2020): 1–17. http://dx.doi.org/10.1155/2020/5861948.

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The linear jet propulsion system, unlike pump-jets which are widely used in underwater bodies, is installed inside a tunnel under the vessel and can be used for high-speed crafts, tugs, and service boats. However, this system has not received adequate attention by researchers, which is the subject of the current study. In the present paper, hydrodynamic performance of the linear jet propulsion system is numerically investigated. Accordingly, the Ansys-CFX software is utilized and RANS equations are solved using the SST turbulent model. The results of the proposed numerical model, in the form of thrust and torque coefficient as well as efficiency, are compared with available experimental data for a ducted propeller, and good compliance is achieved. Considering the importance of stator cross section on the performance of the linear jet propulsion system, the influence of thickness and camber size of the stator on linear jet propulsion systems are examined. Based on the numerical findings, it is determined that at constant advance ratio, with increasing thickness of stator, the efficiency increases. It is also observed that as the span length increases, the maximum and minimum of the pressure coefficient increase for different thicknesses. Furthermore, it is seen that positive and negative pressure coefficients decrease with an increase in foil thickness.

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Chahine, Georges L., Virgil E. Johnson, William T. Lindenmuth, and Gary S. Frederick. "The use of self‐resonating cavitating water jets for underwater sound generation." Journal of the Acoustical Society of America 77, no. 1 (January 1985): 113–26. http://dx.doi.org/10.1121/1.392274.

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Lu, Xiaolong, Zhiwen Wang, Hui Shen, Kangdong Zhao, Tianyue Pan, Dexu Kong, and Jens Twiefel. "A Novel Dual-Rotor Ultrasonic Motor for Underwater Propulsion." Applied Sciences 10, no. 1 (December 19, 2019): 31. http://dx.doi.org/10.3390/app10010031.

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Micro underwater vehicles (MUVs) have been highlighted recently for underwater explorations because of their high maneuverability, low price, great flexibility, etc. The thrusters of most conventional MUVs are driven by electromagnetic motors, which need big mechanical transmission parts and are prone to being interrupted by the variance of ambient electromagnetic fields. In this paper, a novel dual-rotor ultrasonic motor with double output shafts, compact size, and no electromagnetic interference is presented, characterized, and applied for actuating underwater robots. This motor was composed of a spindle-shaped stator, pre-pressure modulation unit, and dual rotors, which can output two simultaneous rotations to increase the propulsion force of the MUV. The pre-pressure modulation unit utilized a torsion spring to adjust the preload at the contact faces between the stator and rotor. The working principle of the ultrasonic motor was developed and the vibration mode of the stator was analyzed by the finite element method. Experimental results show that the no-load rotary speed and stalling torque of the prototype ultrasonic motor were 110 r/min and 3 mN·m, respectively, with 150 V peak-to-peak driving voltage at resonance. One underwater robot model equipped with the proposed ultrasonic motor-powered thruster could move at 33 mm/s immersed in water. The dual-rotor ultrasonic motor proposed here provides another alternative for driving MUVs and is appropriate for developing specific MUVs when the electromagnetic interference issue needs to be considered.

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Sunaryo and Dendi Nurachman. "Propulsion System Analysis For Solar-Powered Electric Water Recreational." E3S Web of Conferences 67 (2018): 04010. http://dx.doi.org/10.1051/e3sconf/20186704010.

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Indonesia is the world’s largest archipelago with more than 17,000 islands, and also the best marine tourism destination, there are many beautiful beaches and underwater spots throughout the country. Due to this potential condition Indonesian government is planning to improve its maritime tourism sector. To realize this boats play very important role both for transport as well as for recreational purposes. On the other hand the government is also committed to reduce the global warming from the use of fossil fuel especially in industry and transportation through the Presidential Regulation no. 61/2011, with the strategy for replacing the fossil fuel with renewable energy. To support the government’s program the research is aimed to design solar-powered electric recreation boat for tourism, with the consideration that there is almost non-stop sun shine available all year long in Indonesia. The boat has length of 12 meters. In this paper the focus is on the analysis of the propulsion system of the boat, which consists of the calculation the power needed to run the electric motor, the optimum propeller design, and the steering system.

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Zhang, Xiaoyuan, Shipeng Li, Dian Yu, Baoyu Yang, and Ningfei Wang. "The Evolution of Interfaces for Underwater Supersonic Gas Jets." Water 12, no. 2 (February 11, 2020): 488. http://dx.doi.org/10.3390/w12020488.

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The evolution of interfaces for underwater gas jets is the main morphological manifestation of two-phase unstable interaction. The high-speed transient photographic recording and image post-processing methods are used to obtain the interfacial change in a submerged gaseous jet at different stages after its ejection from the Laval nozzle exit. The relationship between the pressure pulsation in the wake flow field and the interfacial change is further analyzed by combining the experimental results with computational results. A theoretical model is employed to address the competition dominant mechanism of interface instability. The results show that the jet interface of a supersonic gas jet gradually changes from one containing wave structures to a transition structure, and finally forms a steady-state conical jet. The fluctuation of the jet interface results in the pulsation of the back-pressure. The dominant mechanism of the interface changes with the development and distribution of the jet, from Kelvin-Helmholtz (K-H) instability beyond the nozzle exit changing to Rayleigh-Taylor (R-T) instability in the downstream.

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Wang, Ying, and Yourong Li. "Fault Diagnosis of Underwater Vehicle Propulsion System Based on Deep Learning." Journal of Coastal Research 107, sp1 (August 11, 2020): 65. http://dx.doi.org/10.2112/jcr-si107-017.1.

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Shafer, D., V. Tz Gurovich, D. Yanuka, E. Zvulun, S. Gleizer, G. Toker, and Ya E. Krasik. "Generation of fast cumulative water jets by underwater electrical explosion of conical wire arrays." Journal of Applied Physics 117, no. 1 (January 7, 2015): 015901. http://dx.doi.org/10.1063/1.4905548.

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Waters, Daniel F., and Christopher P. Cadou. "Modeling a hybrid Rankine-cycle/fuel-cell underwater propulsion system based on aluminum–water combustion." Journal of Power Sources 221 (January 2013): 272–83. http://dx.doi.org/10.1016/j.jpowsour.2012.07.085.

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Chen, Xianhe, Zhixun Xia, Liya Huang, and Jianxin Hu. "Optimization of the Working Cycle for an Underwater Propulsion System Based on Aluminium-Water Combustion." IOP Conference Series: Earth and Environmental Science 63 (May 2017): 012022. http://dx.doi.org/10.1088/1755-1315/63/1/012022.

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Yapa, Poojitha D., and Hao Xie. "Modeling Underwater Oil/Gas Jets and Plumes: Comparison with Field Data." Journal of Hydraulic Engineering 128, no. 9 (September 2002): 855–60. http://dx.doi.org/10.1061/(asce)0733-9429(2002)128:9(855).

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Regina, Bruno A., Leonardo M. Honório, Antônio A. N. Pancoti, Mathaus F. Silva, Murillo F. Santos, Vitor M. L. Lopes, Accacio F. Santos Neto, and Luis G. F. Westin. "Hull and Aerial Holonomic Propulsion System Design for Optimal Underwater Sensor Positioning in Autonomous Surface Vessels." Sensors 21, no. 2 (January 15, 2021): 571. http://dx.doi.org/10.3390/s21020571.

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Acoustic Doppler Current Profiler (ADCP) sensors measure water inflows and are essential to evaluate the Flow Curve (FC) of rivers. The FC is used to calibrate hydrological models responsible for planning the electrical dispatch of all power plants in several countries. Therefore, errors in those measures propagate to the final energy cost evaluation. One problem regarding this sensor is its positioning on the vessel. If placed on the bow, it becomes exposed to flowing obstacles, and if it is installed on the stern, the redirected water from the boat and its propulsion system change the sensor readings. To improve the sensor readings, this paper proposes the design of a catamaran-like Autonomous Surface Vessel (ASV) with an optimized hull design, aerial propulsion, and optimal sensor placement to keep them protected and precise, allowing inspections in critical areas such as ultra-shallow waters and mangroves.

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Kalvin, Roman, Juntakan Taweekun, Muhammad Waqas Mustafa, Faisla Ishfaq, and Saba Arif. "Design and Fabrication of Under Water Remotely Operated Vehicle." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 82, no. 1 (April 21, 2021): 133–44. http://dx.doi.org/10.37934/arfmts.82.1.133144.

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Underwater Remotely Operated vehicle is a tethered mobile vehicle most often used to monitor underwater oil and gas drilling inspection, telecommunications and homeland security. The main focus of this research is to design a vehicle at low cost which is safe, portable, and easy to use while increasing the maneuverability and efficiency to reach a depth of 5 meters. While conducting research a unique design is selected based on a novel fin propulsion mechanism rather than propellers. Propellers though have high speed but cannot work on low flow rates and their blades can be damaged if jelly fish or other material is struck in its shaft. Two shapes have been considered to remove above difficulties i.e. Fish and Turtle. Due to higher stability, larger area and greater hydrodynamic efficiency Sea Turtle has been selected, as it can easily overcome the forces like buoyancy, pressure and thrust force. The results extracted from this research shows that the underwater vehicles based on the biological locomotion principle can perform very well than other propeller counterparts. The research concludes with the performance of a working system that validates motion capabilities related to speed, depth and hydrodynamic efficiency which can be further improved by using sophisticated control systems, outer shell and highly integrated processors.

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PERNG, A. T. H., and H. CAPART. "Underwater sand bed erosion and internal jump formation by travelling plane jets." Journal of Fluid Mechanics 595 (January 8, 2008): 1–43. http://dx.doi.org/10.1017/s0022112007008567.

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Theory and experiments are used to investigate the water and sediment motion induced along a sea bed by travelling plane jets. Steadily moving jets are considered, and represent an idealization of the tools mounted on ships and remotely operated vehicles (ROVs) for injection dredging and trenching. The jet-induced turbulent currents simultaneously suspend sand from the bed and entrain water from the ambient. To describe these processes, a shallow-flow theory is proposed in which the turbulent current is assumed stratified into sediment-laden and sediment-free sublayers. The equations are written in curvilinear coordinates attached to the co-evolving bed profile. A sharp interface description is then adopted to account rigorously for mass and momentum exchanges between the bed, current and ambient, including their effects on the balance of mechanical energy. Travelling-wave solutions are obtained, in which the jet-induced current scours a trench of permanent form in a frame of reference moving with the jetting tool. Depending on the operating parameters, it is found that the sediment-laden current may remain supercritical throughout the trench, or be forced to undergo an internal hydraulic jump. These predictions are confirmed by laboratory experiments. For flows with or without jump in which the current remains attached to the bed, bottom profiles computed by the theory compare favourably with imaging measurements.

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Gorma, Wael, Mark A. Post, James White, James Gardner, Yang Luo, Jongrae Kim, Paul D. Mitchell, Nils Morozs, Marvin Wright, and Qing Xiao. "Development of Modular Bio-Inspired Autonomous Underwater Vehicle for Close Subsea Asset Inspection." Applied Sciences 11, no. 12 (June 10, 2021): 5401. http://dx.doi.org/10.3390/app11125401.

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To reduce human risk and maintenance costs, Autonomous Underwater Vehicles (AUVs) are involved in subsea inspections and measurements for a wide range of marine industries such as offshore wind farms and other underwater infrastructure. Most of these inspections may require levels of manoeuvrability similar to what can be achieved by tethered vehicles, called Remotely Operated Vehicles (ROVs). To extend AUV intervention time and perform closer inspection in constrained spaces, AUVs need to be more efficient and flexible by being able to undulate around physical constraints. A biomimetic fish-like AUV known as RoboFish has been designed to mimic propulsion techniques observed in nature to provide high thrust efficiency and agility to navigate its way autonomously around complex underwater structures. Building upon advances in acoustic communications, computer vision, electronics and autonomy technologies, RoboFish aims to provide a solution to such critical inspections. This paper introduces the first RoboFish prototype that comprises cost-effective 3D printed modules joined together with innovative magnetic coupling joints and a modular software framework. Initial testing shows that the preliminary working prototype is functional in terms of water-tightness, propulsion, body control and communication using acoustics, with visual localisation and mapping capability.

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Vracar, Miodrag, and Nenad Kovacevic. "Vibration of the vessel and bispectrum of hydroacoustic noise." Facta universitatis - series: Physics, Chemistry and Technology 7, no. 1 (2009): 45–60. http://dx.doi.org/10.2298/fupct0901045v.

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The origin of vessels vibrations is dominantly determined by vessels propulsion system, auxiliary systems, pumps, breaking of the waves at the ship hull, etc. All of these systems contribute to the appearance of the underwater sound in water environment. As a source of underwater sound, vessels has the characteristic of directivity. Vibration of the vessel's structure is analyzed using spectra, but hydroacoustic signals are analyzed using spectra and higher order spectral analysis - bispectra. The measuring of the radiated hydroacoustic noise was done simultaneously with multi channel measurements of the vessels vibrations at few characteristics positions of the vessel.

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Zhou, Liangliang, and Yonggang Yu. "Study on interaction characteristics between multi gas jets and water during the underwater launching process." Experimental Thermal and Fluid Science 83 (May 2017): 200–206. http://dx.doi.org/10.1016/j.expthermflusci.2017.01.007.

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38

Blintsov, Volodymyr, and Hanna Hrudinina. "Mathematical modeling of autonomous underwater vehicle propulsion and steering complex operation in oblique (beveled) water flow." Eastern-European Journal of Enterprise Technologies 4, no. 9 (100) (August 22, 2019): 19–26. http://dx.doi.org/10.15587/1729-4061.2019.176673.

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Tarełko, Wiesła. "The Effect of Hull Biofouling on Parameters Characterising Ship Propulsion System Efficiency." Polish Maritime Research 21, no. 4 (January 31, 2015): 27–34. http://dx.doi.org/10.2478/pomr-2014-0038.

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Abstract One of most important issues concerning technical objects is the increase of their operating performance. For a ship this performance mainly depends on the efficiency of its main pro-pulsion system and the resistance generated during its motion on water. The overall ship re-sistance, in turn, mainly depends on the hull friction resistance, closely related with the pres-ence of different types of roughness on the hull surface, including underwater part biofouling. The article analyses the effect of hull biofouling on selected parameters characterising the efficiency of the ship propulsion system with adjustable propeller. For this purpose a two-year research experiment was performed on a sailing vessel during its motor navigation phases. Based on the obtained results, three groups of characteristics were worked out for different combinations of engine rotational speed and adjustable propeller pitch settings. The obtained results have revealed that the phenomenon of underwater hull biofouling affects remarkably the parameters characterising propulsion system efficiency. In particular, the development of the biofouling layer leads to significant reduction of the speed of navigation.

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40

Chen, Yuqing, Yaowen Liu, Yangrui Meng, Shuanghe Yu, and Yan Zhuang. "System Modeling and Simulation of an Unmanned Aerial Underwater Vehicle." Journal of Marine Science and Engineering 7, no. 12 (December 4, 2019): 444. http://dx.doi.org/10.3390/jmse7120444.

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Unmanned Aerial Underwater Vehicles (UAUVs) with multiple propellers can operate in two distinct mediums, air and underwater, and the system modeling of the autonomous vehicles is a key issue to adapt to these different external environments. In this paper, only a single set of aerial rotors with switching propulsion abilities are designed as driving components, and then a compound multi-model method is investigated to achieve good performance of the cross-medium motion. Furthermore, some additional variables, such as water resistance, buoyancy and their corresponding moments are considered for the underwater case. In particular, a critical coefficient for air-to-water switching is presented to express these gradually changing additional variables in the cross-medium motion process. Finally, the sliding mode control method is used to reduce the altitude error and attitude error of the vehicles with external environmental disturbances. The proposed scheme is tested and the model is verified on the simulation platform.

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Miao, Tiancheng, Jingting Liu, Shijie Qin, Ning Chu, Dazhuan Wu, and Leqin Wang. "The flow and acoustic characteristics of underwater gas jets from large vertical exhaust nozzles." Journal of Low Frequency Noise, Vibration and Active Control 37, no. 1 (March 2018): 74–89. http://dx.doi.org/10.1177/1461348418761688.

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The flow and acoustic characteristics of underwater gas jets exhausted from large vertical nozzles are experimentally investigated in this work with gas flow rates of 30–150 m3/h, nozzle widths of d = 10 mm, 20 mm, 30 mm, and 40 mm. A high-speed digital video camera is used to examine bubble behavior and flow regimes. Sound pressure is measured by two hydrophones and recorded by a digital audio tape recorder. The audio and video signals are synchronized to find out the relationship between sound and gas behavior. Experimental results indicate that the general behavior of gas exhausted into water is of periodical necking and expansion. Sound pressure peaks are mostly excited by necking in two ways: pinch-off and redial expansion. Necking itself is a kind of low frequency behavior, corresponding to strong low frequency sounds. Moreover, necking can force the growing bubble to oscillate and emit broadband sound. As the gas velocity increases, necking would happen more frequently, and gas jets would grow into larger volume in shorter time, and then the sound radiated from the gas jets would have higher frequency and larger amplitude.

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Wang, Hai-Long, Xing-Ya Yan, Gang Wang, Qi-Feng Zhang, Qi-Yan Tian, and Yun-Long Fan. "Experimental research and floating gait planning of crablike robot." Advances in Mechanical Engineering 12, no. 2 (February 2020): 168781402090485. http://dx.doi.org/10.1177/1687814020904853.

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In order to improve the swimming performance of a paddle-propelled crablike robot, the sequence and parameters of swimming gait are planned according to the bionic swimming mechanism. Based on the bionic prototype of Portunus trituberculatus, the structure scheme of a leg–paddle hybrid driven robot is proposed with the functions of walking on land, crawling on seabed, and swimming underwater. By analyzing the underwater propulsion mechanism of single paddle and hydrodynamic performance of double paddles cooperatively propulsion, four direct swimming gaits are planned and the corresponding attitude changes are theoretically analyzed. Then, the numerical simulation and direct swimming experiments are carried out to verify the effectiveness of proposed gaits and correctness of force analysis. In alternate swimming gait of lift-based mode, the robot swims forward in a rolling attitude, with an advantage of the minimum water resistance and the optimum swimming velocity and efficiency. The influence of flapping frequency and relative phases of paddles on the swimming velocity shows the trend of raise first and then fall.

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Kim, Nayoung, and Hyungmin Park. "Water entry of rounded cylindrical bodies with different aspect ratios and surface conditions." Journal of Fluid Mechanics 863 (January 28, 2019): 757–88. http://dx.doi.org/10.1017/jfm.2018.1026.

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In the present study, we experimentally investigate water surface deformation due to the impact of rounded cylindrical projectiles with different aspect ratios (1.0–8.0). The subsequent jet and splash formation is closely related to the dynamics of an underwater cavity. To control the cavity formation, two kinds of surface conditions (smooth and rough) are applied to the front parts of the projectiles, and two impact speeds are considered. The Froude, Reynolds and Weber numbers are in the ranges of 32–90, $5\times 10^{4}{-}8.4\times 10^{4}$ and 1700–5000, respectively. When the front is smooth, the water film rises up along the body surface immediately after impact, and the temporal variation of its height is analytically estimated. The film converges at the rear pole to create an apex jet at lower aspect ratios and simply rises up and falls with the body at higher aspect ratios. The jets could be further distinguished as thin and thick jets, whose breakdown is found to be a function of the viscous force and surface tension, i.e. the Ohnesorge number. On the other hand, when the front is rough, the water film cannot rise up along the body surface, and instead early separation occurs to make the splash above a free surface. The splash size is quantified to assess the effects of the aspect ratio and impact speed. Upon splash formation, a cavity is created under the free surface, which emanates from the nose of the projectile. As the body sinks, the cavity pinch-off occurs due to the imbalance between the hydrostatic pressure and air pressure inside the cavity. At higher aspect ratios, cavity pinch-off occurs on the side wall of the projectile and leaves a portion of the cavity bubble on it. When the surface is smooth, no underwater cavity forms. Finally, we compare the hydrodynamic force acting on the sinking bodies with and without cavity formation, based on the underwater trajectory of each projectile. It is found that the underwater cavity reduces the drag force on the sinking body when it fully encapsulates the body; however, if the air bubbles are partially attached to the body after pinch-off, they tend to detach irregularly or impose additional drag on the body.

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Piskur, Pawel, Piotr Szymak, Zygmunt Kitowski, and Leszek Flis. "Influence of Fin’s Material Capabilities on the Propulsion System of Biomimetic Underwater Vehicle." Polish Maritime Research 27, no. 4 (December 1, 2020): 179–85. http://dx.doi.org/10.2478/pomr-2020-0078.

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Abstract The technology of Autonomous Underwater Vehicles (AUVs) is developing in two main directions focusing on improving autonomy and improving construction, especially driving and power supply systems. The new Biomimetic Underwater Vehicles (BUVs) are equipped with the innovative, energy efficient driving system consisting of artificial fins. Because these driving systems are not well developed yet, there are great possibilities to optimize them, e.g. in the field of materials. The article provides an analysis of the propulsion force of the fin as a function of the characteristics of the material from which it is made. The parameters of different materials were used for the fin design and their comparison. The material used in our research was tested in a laboratory to determine the Young’s modulus. For simplicity, the same fin geometry (the length and the height) was used for each type of fin. The Euler–Bernoulli beam theory was applied for estimation of the fluid–structure interaction. This article presents the laboratory test stand and the results of the experiments. The laboratory water tunnel was equipped with specialized sensors for force measurements and fluid–structure interaction analysis. The fin deflection is mathematically described, and the relationship between fin flexibility and the generated driving force is discussed.

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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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Tran, Minh, Jonathan Binns, Shuhong Chai, Alexander L. Forrest, and Hung Nguyen. "A practical approach to the dynamic modelling of an underwater vehicle propeller in all four quadrants of operation." Proceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment 233, no. 1 (November 30, 2017): 333–44. http://dx.doi.org/10.1177/1475090217744906.

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This article presents the open water propeller characteristics and the four-quadrant propeller models as applied to a torpedo-shaped underwater vehicle. A series of experiments with a Gavia autonomous underwater vehicle propeller were conducted in the towing tank using a rotor testing apparatus. The purpose of these tests was to measure the propeller thrust and torque under varying flow conditions and then to be used as the basis of the developed propeller models. These mathematical models were constructed using two regression models, a polynomial and a Fourier series. Model coefficients were derived using the method of least squares and a comparison analysis was also conducted to test the robustness of the methodology. Results show that the Fourier series models were able to produce a reasonable and accurate approximation of thrust and torque coefficients with a small number of parameters in the examined condition of this study. The obtained four-quadrant open water characteristics of the autonomous underwater vehicle propeller model would be utilised to improve the system mathematical model for more accurate simulation and controller design, to compare the autonomous underwater vehicle performance equipped with different propulsion units, and to validate computational fluid dynamic results.

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Li, Yukai, Yuli Hu, Youguang Guo, Baowei Song, and Zhaoyong Mao. "Analytical Modeling and Design of Novel Conical Halbach Permanent Magnet Couplings for Underwater Propulsion." Journal of Marine Science and Engineering 9, no. 3 (March 6, 2021): 290. http://dx.doi.org/10.3390/jmse9030290.

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Permanent magnet couplings can convert a dynamic seal into a static seal, thereby greatly improving the stability of the underwater propulsion unit. In order to make full use of the tail space and improve the transmitted torque capability, a conical Halbach permanent magnet coupling (C-HPMC) is proposed in this paper. The C-HPMC combines multiple cylindrical HPMCs with different sizes into an approximately conical structure. Compared with the conical permanent magnet couplings in our previous work, the novel C-HPMC has better torque performance and is easy to process. The analytical calculation method of transmitted torque of C-HPMC is proposed on the basis of torque calculation of the three common types of HPMCs. The accuracy of the torque calculation of the three HPMCs is verified, and the torque performance of the three HPMCSs of different sizes is compared and discussed. The “optimal type selection” method is proposed and applied in the design of C-HPMC. Finally, on the basis of torque analysis calculation and axial force calculation, a complete flowchart of the design and performance analysis of C-HPMC is described.

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48

Lin, Xichuan, Shuxiang Guo, Chunfeng Yue, and Juan Du. "3D Modelling of a Vectored Water Jet-Based Multi-Propeller Propulsion System for a Spherical Underwater Robot." International Journal of Advanced Robotic Systems 10, no. 1 (January 2013): 80. http://dx.doi.org/10.5772/51537.

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Park, Eun-Young, and Jungho Choi. "The Performance of Low-Pressure Seawater as a CO2 Solvent in Underwater Air-Independent Propulsion Systems." Journal of Marine Science and Engineering 8, no. 1 (January 3, 2020): 22. http://dx.doi.org/10.3390/jmse8010022.

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Air-independent propulsion systems have improved the performance and decreased the vulnerability of underwater weapon systems. Reforming systems, however, generates large amounts of water and CO2. The recovery or separation of CO2, a residual gas component generated in vessels, entails considerable cost and energy consumption. It is necessary to understand the characteristics of the interaction between CO2 and seawater under the conditions experienced by underwater weapon systems to design and optimize a CO2 treatment process for dissolving CO2 in seawater. In this study, numerical analysis was conducted using the derived experimental concentration and MATLAB. The diffusion coefficient was derived as a function of temperature according to the CO2 dissolution time. Experiments on CO2 dissolution in seawater were conducted. The concentration of CO2 according to the reaction pressure and experimental temperature was obtained. The diffusion coefficient between CO2 and seawater was found to be 6.3 × 10−5 cm2/s at 25 °C and 7.24 × 10−5 cm2/s at 32 °C. CO2 concentration could be estimated accurately under vessel operating conditions using the derived CO2 diffusion coefficients. Optimal design of the residual gas treatment process will be possible using the derived seawater–CO2 diffusion coefficients under the actual operating conditions experienced by underwater weapon systems.

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Sutherland, Kelly R., Brad J. Gemmell, Sean P. Colin, and John H. Costello. "Maneuvering Performance in the Colonial Siphonophore, Nanomia bijuga." Biomimetics 4, no. 3 (September 5, 2019): 62. http://dx.doi.org/10.3390/biomimetics4030062.

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The colonial cnidarian, Nanomia bijuga, is highly proficient at moving in three-dimensional space through forward swimming, reverse swimming and turning. We used high speed videography, particle tracking, and particle image velocimetry (PIV) with frame rates up to 6400 s−1 to study the kinematics and fluid mechanics of N. bijuga during turning and reversing. N. bijuga achieved turns with high maneuverability (mean length–specific turning radius, R/L = 0.15 ± 0.10) and agility (mean angular velocity, ω = 104 ± 41 deg. s−1). The maximum angular velocity of N. bijuga, 215 deg. s−1, exceeded that of many vertebrates with more complex body forms and neurocircuitry. Through the combination of rapid nectophore contraction and velum modulation, N. bijuga generated high speed, narrow jets (maximum = 1063 ± 176 mm s−1; 295 nectophore lengths s−1) and thrust vectoring, which enabled high speed reverse swimming (maximum = 134 ± 28 mm s−1; 37 nectophore lengths s−1) that matched previously reported forward swimming speeds. A 1:1 ratio of forward to reverse swimming speed has not been recorded in other swimming organisms. Taken together, the colonial architecture, simple neurocircuitry, and tightly controlled pulsed jets by N. bijuga allow for a diverse repertoire of movements. Considering the further advantages of scalability and redundancy in colonies, N. bijuga is a model system for informing underwater propulsion and navigation of complex environments.

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Journal articles on the topic 'Water jets Underwater propulsion'

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