Journal articles: 'Hydrodynamic efficiency'

1

Garcia, Paulo A., Zhifei Ge, Laura E. Kelley, Steven J. Holcomb, and Cullen R. Buie. "High efficiency hydrodynamic bacterial electrotransformation." Lab on a Chip 17, no. 3 (2017): 490–500. http://dx.doi.org/10.1039/c6lc01309k.

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Gutiérrez, A., M. C. Álvarez, J. H. Gaviño, and N. Carbajal. "Theoretical hydrodynamic efficiency of coccoliths." Marine Micropaleontology 152 (September 2019): 101746. http://dx.doi.org/10.1016/j.marmicro.2019.04.005.

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Naemi, Roozbeh, William J. Easson, and Ross H. Sanders. "Hydrodynamic glide efficiency in swimming." Journal of Science and Medicine in Sport 13, no. 4 (July 2010): 444–51. http://dx.doi.org/10.1016/j.jsams.2009.04.009.

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Belincanta, Juliana, Teresa Massako Kakuta Ravagnani, and João Alexandre Ferreira Pereira. "The Parastillation Efficiency and Hydrodynamic Behaviour." Canadian Journal of Chemical Engineering 83, no. 3 (May 19, 2008): 582–85. http://dx.doi.org/10.1002/cjce.5450830324.

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Basko, M. M. "Hydrodynamic efficiency of illumination by ion beams." Laser and Particle Beams 8, no. 3 (September 1990): 409–19. http://dx.doi.org/10.1017/s026303460000865x.

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The hydrodynamic efficiency of conversion of the energy of fast charged particles into the kinetic energy of the bulk motion of plane-parallel shells is investigated in the framework of two simple models–one based on the stepwise density profile and the other employing a self-similar solution. The analytical estimates obtained are substantiated with ID hydrodynamic calculations. In case of spherical shells, the three key dimensionless parameters determining the values of the hydrodynamic efficiency are pointed out; the dependence of the hydrodynamic efficiency on these parameters has been explored numerically. The effects of a nonuniform energy deposition (increasing by the end of the fast particle ranges) and of a nonuniform absorber composition are also discussed.

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Cwudziński, Adam, and Bernadeta Gajda. "Particle Image Velocimetry Method for Prediction Hydrodynamic Conditions during Leaching Process on the Basis of Sn–NaOH System." Materials 14, no. 3 (January 29, 2021): 633. http://dx.doi.org/10.3390/ma14030633.

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In leaching processes controlled by diffusion and convectional transport of mass, the hydrodynamic structure formed in the reactor’s working volume is an additional factor affecting the process. This research work presents results related to hydrodynamic structures developing in batch reactors, different in shape, recorded by means of the particle image velocimetry (PIV) method. The movement of the distilled water and leaching solution was analyzed during investigations. Next, the system hydrodynamics and the process of tin leaching were analyzed. Finally, the leaching is affected by the reactor geometry and the hydrodynamic structure developed in its working volume, especially when a convectional or diffusion mass transport decides the process efficiency.

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Sanmartin, J. R., J. L. Montanes, J. Sanz, and R. Ramis. "The hydrodynamic efficiency of laser-target acceleration." Plasma Physics and Controlled Fusion 27, no. 9 (September 1, 1985): 983–93. http://dx.doi.org/10.1088/0741-3335/27/9/004.

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McCALLUM, DONALD, ALLEN H. ENGLE, GREGORY P. PLATZER, and GABOR KARAFIATH. "Hydrodynamic Efficiency Improvements for U.S. Navy Ships." Naval Engineers Journal 103, no. 3 (May 1991): 74–90. http://dx.doi.org/10.1111/j.1559-3584.1991.tb00939.x.

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PLATZER, GREGORY P., DONALD N. MCCALLUM, GABOR KARAFIATH, and ALLEN H. ENGLE. "HYDRODYNAMIC EFFICIENCY IMPROVEMENTS FOR U.S. NAVY SHIPS." Naval Engineers Journal 103, no. 4 (July 1991): 102–4. http://dx.doi.org/10.1111/j.1559-3584.1991.tb01000.x.

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Vorus, William S., and Brandon M. Taravella. "Anguilliform fish propulsion of highest hydrodynamic efficiency." Journal of Marine Science and Application 10, no. 2 (June 2011): 163–74. http://dx.doi.org/10.1007/s11804-011-1056-3.

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Melnik, V. A. "Efficiency of hydrodynamic devices in slot seals." Chemical and Petroleum Engineering 49, no. 1-2 (May 2013): 126–32. http://dx.doi.org/10.1007/s10556-013-9714-8.

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Makarov, V., V. Potapov, E. Churakov, and N. Makarov. "Ways to improve the energy efficiency of shaft centrifugal pumps." Transbaikal State University Journal 27, no. 5 (2021): 26–35. http://dx.doi.org/10.21209/2227-9245-2021-27-5-26-35.

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The increase in the efficiency and competitiveness of mining enterprises is limited by the insufficient efficiency and adaptability of the currently used centrifugal pumps. Using the vortex theory of turbomachines, Theorems Stokes’ and Helmholtz, the principles of hydrodynamic analogy and superpositions, a mathematical model of the hydrodynamic calculation of centrifugal pumps with adaptive vortex sources integrated into the impeller blades is obtained. A significant influence on the hydrodynamic parameters and adaptability of pumps of the energy characteristics of adaptive vortex sources has been proved. Criteria for the similarity of the hydrodynamic process of fluid flow in the interscapular channels of impellers and adaptive vortex sources and their influence on the hydrodynamic characteristics of pumps are obtained. Mathematical and experimental modeling uses a regression equation to calculate the parameters of vortex chambers and their impact on the efficiency and adaptability of pumps. The optimal geometric parameters of the vortex chambers, the diameter of which does not exceed 5…7 % of the impeller diameter, increase the hydrodynamic loading by at least 13 %, the nominal efficiency. not less than 6 %, adaptability not less than 8 %. On the basis of the proposed developed mathematical model, after the positive test results obtained on the laboratory pump K 20/30, tests were carried out on the CNS 300-300 pump

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Bashmur, K. A., E. A. Petrovsky, V. S. Tynchenko, V. V. Bukhtoyarov, R. B. Sergienko, and O. A. Kolenchukov. "Effects of a rough surface vortex breaker hydrocyclone on the separating capacity of heterogeneous fluid systems." SOCAR Proceedings, SI2 (December 30, 2021): 13–20. http://dx.doi.org/10.5510/ogp2021si200580.

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This paper considers the issue of heterogeneous system separation efficiency under the action of centrifugal forces working in hydrocyclones. The main problem with these apparatuses is related to vortex forming. The paper describes the negative effects of vortexes on the heterogeneous medium separation process. A hydrocyclone design was developed and described, which improves the hydrocyclone separation capacity. This design introduces a vortex breaker. Furthermore, vortex formation can be eliminated or minimized by providing the vortex breaker with a rough surface. To determine the separation efficiency and the adequacy of the proposed solution, hydrodynamic computer simulation and experimental studies were conducted. Solidworks Flow Simulation software was used for hydrodynamic computer simulation. To check the medium separation degree, an experimental study was conducted showing improvement of the hydrocyclone separation capacity efficiency by 3% in the developed apparatus compared to conventional hydrocyclone designs. Keywords: hydrocyclone; separation; separating capacity; vortex breaker; heterogeneous system; oil preparation; hydrodynamics.

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Zhang, Fu Ying, Qing Qing Zhang, and Ping Wang. "Efficiency- Reinforcement Technology Study for Hydraulic Reciprocating Sealing Based on TRIZ S-Field Analysis." Advanced Materials Research 97-101 (March 2010): 4433–36. http://dx.doi.org/10.4028/www.scientific.net/amr.97-101.4433.

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The dynamic seal mechanism of hydrodynamic reciprocating sealing is discussed. TRIZ S-Field model and standard solutions is proposed. The reliability and effectivity S-Field models of hydrodynamic reciprocating sealing are constructed according to typical hydrodynamic reciprocating sealing configuration shapes, such as O-ring sealing, Y-ring sealing and polymer sealing. The leakage and failure problems solutions of hydrodynamic reciprocating sealing as well as their configuration realization are studied based on TRIZ S-Field analysis and standard solutions, which offer powerful theoretic guides for efficiency-reinforcement technology of hydrodynamic reciprocating sealing.

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Persson, J., N. L. G. Somes, and T. H. F. Wong. "Hydraulics Efficiency of Constructed Wetlands and Ponds." Water Science and Technology 40, no. 3 (August 1, 1999): 291–300. http://dx.doi.org/10.2166/wst.1999.0174.

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Constructed ponds and wetlands are widely used in urban design to serve a number of functions including stormwater management. The design of constructed wetlands for stormwater management involves a number of multi-disciplinary inputs. Fundamental to their sustainable operation are the proper control of the hydrologic regime of the wetland and optimal flow hydrodynamics within the wetland. Many ofthe problems encountered in constructed wetlands can be minimised or avoided by good engineering design principles. Poor wetland hydrodynamics are often identified as a major contributor to wetland management problems. Ponds and wetlands with a high hydraulic efficiency are expected to promote full utilisation ofthe available detention storage and near plug flow conditions. The shape and layout of urban ponds and wetlands are often varied to suit the landscape and to satisfy aesthetic requirements as an urban water feature. These can be achieved while maintaining an effective stormwater treatment outcome if steps are taken to ensure that the hydrodynamic behaviour of the system is not severely compromised. A consistent measure is required to allow the effects of design features to be evaluated against this criterion. This paper introduces a new measure for hydraulic efficiency that combines existing measures of flow uniformity and effective volume. Case studies are presented on the use of this measure to assess the effects of different pond and wetland shapes, locations of inlet and outlet, botanical layouts and basin morphology on the flow hydrodynamics.

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16

Belincanta, J., T. M. Kakuta Ravagnani, and J. A. F. Pereira. "Hydrodynamic and tray efficiency behavior in parastillation column." Brazilian Journal of Chemical Engineering 23, no. 1 (March 2006): 135–46. http://dx.doi.org/10.1590/s0104-66322006000100015.

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Rageh, Osami. "Hydrodynamic Efficiency of Floating Breakwaters WITH Plates (Dept.C)." MEJ. Mansoura Engineering Journal 34, no. 2 (November 26, 2020): 126–41. http://dx.doi.org/10.21608/bfemu.2020.125669.

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18

Danis, Umit, Reza Rasooli, Chia-Yuan Chen, Onur Dur, Metin Sitti, and Kerem Pekkan. "Thrust and Hydrodynamic Efficiency of the Bundled Flagella." Micromachines 10, no. 7 (July 4, 2019): 449. http://dx.doi.org/10.3390/mi10070449.

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The motility mechanism of prokaryotic organisms has inspired many untethered microswimmers that could potentially perform minimally invasive medical procedures in stagnant fluid regions inside the human body. Some of these microswimmers are inspired by bacteria with single or multiple helical flagella to propel efficiently and fast. For multiple flagella configurations, the direct measurement of thrust and hydrodynamic propulsion efficiency has been challenging due to the ambiguous mechanical coupling between the flow field and mechanical power input. To address this challenge and to compare alternative micropropulsion designs, a methodology based on volumetric velocity field acquisition is developed to acquire the key propulsive performance parameters from scaled-up swimmer prototypes. A digital particle image velocimetry (PIV) analysis protocol was implemented and experiments were conducted with the aid of computational fluid dynamics (CFD). First, this methodology was validated using a rotating single-flagellum similitude model. In addition to the standard PIV error assessment, validation studies included 2D vs. 3D PIV, axial vs. lateral PIV and simultaneously acquired direct thrust force measurement comparisons. Compatible with typical micropropulsion flow regimes, experiments were conducted both for very low and higher Reynolds (Re) number regimes (up to a Re number = 0.01) than that are reported in the literature. Finally, multiple flagella bundling configurations at 0°, 90° and 180° helical phase-shift angles were studied using scaled-up multiple concentric flagella thrust elements. Thrust generation was found to be maximal for the in-phase (0°) bundling configuration but with ~50% lower hydrodynamic efficiency than the single flagellum. The proposed measurement protocol and static thrust test-bench can be used for bio-inspired microscale propulsion methods, where direct thrust and efficiency measurement are required.

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Isakov, Vladimir A., Andrey P. Kanavin, and A. S. Nasibov. "Hydrodynamic efficiency of laser-induced transfer of matter." Quantum Electronics 37, no. 4 (April 30, 2007): 405–8. http://dx.doi.org/10.1070/qe2007v037n04abeh013427.

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20

Pollaine, S. M., and J. D. Lindl. "Effect of capsule aspect ratio on hydrodynamic efficiency." Nuclear Fusion 26, no. 12 (December 1, 1986): 1719–23. http://dx.doi.org/10.1088/0029-5515/26/12/013.

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21

Shum, H., E. A. Gaffney, and D. J. Smith. "Modelling bacterial behaviour close to a no-slip plane boundary: the influence of bacterial geometry." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 466, no. 2118 (January 13, 2010): 1725–48. http://dx.doi.org/10.1098/rspa.2009.0520.

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We describe a boundary-element method used to model the hydrodynamics of a bacterium propelled by a single helical flagellum. Using this model, we optimize the power efficiency of swimming with respect to cell body and flagellum geometrical parameters, and find that optima for swimming in unbounded fluid and near a no-slip plane boundary are nearly indistinguishable. We also consider the novel optimization objective of torque efficiency and find a very different optimal shape. Excluding effects such as Brownian motion and electrostatic interactions, it is demonstrated that hydrodynamic forces may trap the bacterium in a stable, circular orbit near the boundary, leading to the empirically observable surface accumulation of bacteria. Furthermore, the details and even the existence of this stable orbit depend on geometrical parameters of the bacterium, as described in this article. These results shed some light on the phenomenon of surface accumulation of micro-organisms and offer hydrodynamic explanations as to why some bacteria may accumulate more readily than others based on morphology.

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Vega, G. P., M. R. Peña, C. Ramírez, and D. D. Mara. "Application of CFD modelling to study the hydrodynamics of various anaerobic pond configurations." Water Science and Technology 48, no. 2 (July 1, 2003): 163–71. http://dx.doi.org/10.2166/wst.2003.0111.

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The simulation of hydrodynamics and transport phenomena in waste stabilization ponds is a developing tool worth studying in order to understand their internal processes and interactions. Pond design involves several physical, hydrological, geometric and dynamic variables so as to provide high hydrodynamic efficiency and maximum substrate utilization rates. CFD modelling allows the combination of these factors to predict the behaviour of ponds having different configurations. The two-dimensional depth-integrated model MIKE 21 was used in this study to simulate hydrodynamic and advection-dispersion processes in a full-scale anaerobic pond (AP) located in southwest Colombia. A set of 12 configurations including sludge contents, inlet-outlet positioning, baffling and pond geometry were modelled. Results showed that a crosswise (diagonally opposite) inlet-outlet layout, a length-to-breadth ratio of 2:1, plus provision of two cross baffles at 1/3 L and 2/3 L were the most effective measures to improve overall AP hydrodynamics and dispersion patterns.

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Salimov, Zakirzhan, Oibek Ismailov, Shamshidinhuzha Saydahmedov, and Gennadiy Zaikov. "Influence of Hydrodynamic Regimes of Oil and Gas Mixtures on the Efficiency of Heat Exchange." Vestnik Volgogradskogo gosudarstvennogo universiteta. Serija 10. Innovatcionnaia deiatel’nost’, no. 1 (March 2015): 25–33. http://dx.doi.org/10.15688/jvolsu10.2015.1.4.

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Fesenko, Anatolii, Yevheniia Basova, Vitalii Ivanov, Maryna Ivanova, Fatyma Yevsiukova, and Magomediemin Gasanov. "Increasing of Equipment Efficiency by Intensification of Technological Processes." Periodica Polytechnica Mechanical Engineering 63, no. 1 (December 4, 2018): 67–73. http://dx.doi.org/10.3311/ppme.13198.

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Issues of technological processes’ intensification and increase of technological equipment efficiency are of priority value in the modern engineering. Application of various methods of hydrodynamic drag on the working fluids in rotary-wheel machines allows increasing of processing efficiency to receive finely-dispersed homogeneous mixtures with necessary characteristics. In this article the issues, connected with the liquid flows' formation in the working zone of rotary-cavitating activator are studied and the main principles of energy impact while the usage of rotor with radial channels, supplied with the elements for receiving cavitating effects, are defined. Based on the offered methodology, experimental research was conducted and calculations of the main indexes, defining efficiency of energy impact on the working medium, were held. The substantiated estimation of efficiency of hydrodynamic machines work according to the dissipative power that allows to choose the proportion of hydrodynamic settings, which provide the highest intensity of cavitating processing of processed liquids, was presented. The practical value of the research is in the studying of ways of increasing of equipment efficiency through the possibility of technological process intensification.

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Sánchez-Caja, A., J. Martio, and V. M. Viitanen. "A new propulsion concept for high propulsive hydrodynamic efficiency." Ocean Engineering 243 (January 2022): 110298. http://dx.doi.org/10.1016/j.oceaneng.2021.110298.

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Gronowska-Szneler, M. A., and J. M. Sawicki. "Simple design criteria and efficiency of hydrodynamic vortex separators." Water Science and Technology 70, no. 3 (May 27, 2014): 457–63. http://dx.doi.org/10.2166/wst.2014.245.

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Vortex separators still draw attention from specialists investigating the process of removing particles suspended in liquids. The devices are locally applied for waste water treatment in different systems – from storm waste water sewerage to water circulation in fish ponds. However, the methods for separator design presented in the literature are questionable. The paper presents two simple and functional criteria that were employed to construct a laboratory test stand. The test results gave positive feedback on the efficiency of vortex separators.

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Rageh, O. S., A. S. Koraim, and T. N. Salem. "Hydrodynamic efficiency of partially immersed caissons supported on piles." Ocean Engineering 36, no. 14 (October 2009): 1112–18. http://dx.doi.org/10.1016/j.oceaneng.2009.06.009.

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Morais, Jorge Estrela, Mario J. Costa, Pedro Forte, Mario C. Marques, Antonio J. Silva, Daniel A. Marinho, and Tiago M. Barbosa. "Longitudinal intra- and inter-individual variability in young swimmers' performance and determinant competition factors." Motriz: Revista de Educação Física 20, no. 3 (September 2014): 292–302. http://dx.doi.org/10.1590/s1980-65742014000300008.

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The main purpose of this study was to follow-up the intra- and inter-individual variability of young swimmers' performance and determinant factors over two competitive seasons. Thirty young swimmers (14 boys: 12.33±0.65 years-old; 16 girls: 11.15±0.55 years-old) were followed-up throughout two consecutive seasons (seven evaluation moments). Performance (100m freestyle), anthropometric, kinematic, hydrodynamic and efficiency features were evaluated. A gender and skill-level effect was observed. Boys improved in a higher amount (%) comparing to girls. Overall, swimmers in skill-level 2 (both genders) presented a higher intra-individual variability. Performance and anthropometrics showed a significant inter-individual variability in most moments, but hydrodynamics, kinematics and efficiency did not. Within each skill-level hydrodynamics, kinematics and efficiency were the variables that showed a high inter-individual variability. As a gender and skill-level effect was noticed in an age-group of young swimmers, coaches and practitioners should put the focus in specific and customized training plans for each skill-level of swimmers.

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Makarenko, A. A. "RESEARCH OF THE APPLICATION EFFICIENCY OF DIFFERENT CONSTRUCTIONS OF FLOW CAVITATION MIXERS." Thermophysics and Thermal Power Engineering 41, no. 1 (October 25, 2018): 74–81. http://dx.doi.org/10.31472/ttpe.1.2019.10.

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The material which is accumulated for today about the application of hydrodynamic cavitation in technological processes makes it possible to determine the perspective areas of its use - in the processes of mass transfer, mixing, dissolution, dispersion and emulsification in the processing of liquid heterogeneous systems and the creation of modern energy-saving technologies. The purpose of this article is to study the effectiveness of the use of different designs of flow cavitation mixers for the treatment of liquid heterogeneous disperse systems and to identify the main industries for their use. Cavitational apparatus can be effectively used in performing such technological processes as mixing difficult to mix liquids, dissolving solids in liquids, obtaining stable, multicomponent high dispersion emulsions without using of stabilizers, dispersing suspensions in liquid-liquid systems, accelerating extraction and diffusion, and many others. Hydrodynamic cavitation can be used in technologies to produce lubricants, fuel materials, varnishes and paints, building materials, detergents, etc. Different designs of cavitation devices allow to obtain different forms of cavitation, different ways of obtaining it or their combination, depending on the purpose and field of use. Apparatus whose action is based on the use of hydrodynamic cavitation represent an effective equipment that accelerates technological processes in liquid media while significantly reducing the specific energy consumption. The structures of hydrodynamic cavitation devices provide multiple rearrangements of the velocity field and change the direction of fluid flow and mix components. The main feature of the devices is small dimensions with high performance. Distinctive features of this type of equipment are ensuring the continuity of the chemical-technological process and its high intensification, the possibility of realizing large quantities of deformations and strain of displacement, intensive hydrodynamic and cavitation effects, which results in high-quality mixing of components, intensification of diffusion processes, simplicity and reliability of hardware design. The economic efficiency of the application of hydrodynamic cavitational apparatus is determined by the low metal capacity of the equipment, low maintenance and operation costs compared with capacitive mixing equipment.

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Kurbatov, A. Yu, E. N. Kuzin, Yu M. Averina, M. A. Vetrova, and A. V. Sitnikov. "Investigating the Processes of Hydrodynamic Artesian Water Treatment." Herald of the Bauman Moscow State Technical University. Series Natural Sciences, no. 2 (95) (April 2021): 118–33. http://dx.doi.org/10.18698/1812-3368-2021-2-118-133.

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The paper aims to investigate hydrodynamic treatment processes of raw (artesian) groundwater to be used for household needs and drinking. The main advantage of hydrodynamic raw water treatment is that a single device, a so-called hydrodynamic vibration generator, is enough to perform the most important processing (deferrization, manganese removal, aeration) without any additional reactants. A hydrodynamic vibration generator contributes to accelerating mass exchange processes without using additional chemical reactants, solely by means of the kinetic energy inherent in the raw water flow undergoing treatment, which is generated when the hydrodynamic properties of the flow itself change dramatically. The generator by itself does not purify water; it processes raw water so as to derive insoluble products by recombining the forms in which the substances to be removed are found in the water, that is, by transforming dissolved manganese and iron compounds into insoluble compounds and decreasing carbon dioxide content in the water so as to precipitate insoluble calcium compounds. The resulting insoluble compounds are easy to remove via further processing in a ceramic membrane filtration system. Hydrodynamic vibration generator efficiency depends on many factors, which means that, when implementing hydrodynamic raw water treatment in real life, obtaining fundamental laws governing the treatment processes as functions of respective parametric characteristics is a necessary stage so as to ensure maximum efficiency. Our experiment confirmed that a phenomenon known as sonoluminescence occurs in raw water subjected to hydrodynamic treatment. We propose a monitoring technology indirectly confirming the efficiency of the hydrodynamic raw water treatment implemented, which is based on recording the sonoluminescence phenomenon via an acoustic technique

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Paggi, Marco, Andrea Amicarelli, and Pietro Lenarda. "SPH Modelling of Hydrodynamic Lubrication along Rough Surfaces." Lubricants 7, no. 12 (November 21, 2019): 103. http://dx.doi.org/10.3390/lubricants7120103.

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Rough and textured surfaces are of paramount importance for lubrication, both in nature and in technology. While surface roughness relevantly influences both friction and wear, artificial surface texturing improves the performance of slider bearings as an energy efficiency action. The simulation of hydrodynamic lubrication by taking into account complex surfaces as boundaries requires the use of computational fluid dynamics (CFD) software able to predict the pressure and the velocity profile through the thickness of the fluid and at any point within the 3D domain. In the present study, a CFD–smoothed particle hydrodynamics (SPH) code is applied to simulate hydrodynamic lubrication for a linear slider bearing in the presence of a 3D rough surface, showing the capabilities of CFD–SPH in modelling such complex interaction phenomena. Numerical assessments involve the load capacity, the 3D fields of the velocity vector, and the pressure 3D field (both within the fluid domain and at the fluid–plate interface).

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V, Dobref. "Aspects of Optimizing the Magneto Hydrodynamic Naval Thrusters." Scientific Bulletin of Naval Academy XIX, no. 1 (July 15, 2018): 463–67. http://dx.doi.org/10.21279/1454-864x-18-i1-070.

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In this paper, the authors analyze several problems relating to the efficiency of an MHD thruster. In this regard have been defined, calculated and shown by graphs the propulsive efficiency as a function of the magnetic field flux density, used for different thruster sizes. Finally, it was draw the conclusions about the number of necessary thrusters for a maximal efficiency.

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Aminev, D. A., and M. N. Kravchenko. "Determining reservoir parameters with nonisothermal real gas flow." IOP Conference Series: Materials Science and Engineering 1201, no. 1 (November 1, 2021): 012011. http://dx.doi.org/10.1088/1757-899x/1201/1/012011.

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Abstract Creation and developing methods of determining gas reservoir properties are one of the most important gas hydrodynamics tasks as production project efficiency and reservoir exploitation depend upon layer properties knowledge. Nonstationary gas hydrodynamics investigations are one of the base well and layer researching methods. Results of these investigations are interpreted based on solving of linear isothermal gas flow equation. The current investigation describes the nonstationary gas hydrodynamic survey results interpretation algorithm, which is based on nonlinear equations system solving. The system consists of nonlinear nonisothermal real gas flow and energy equations accounting well influence, Joule-Thompson and adiabatic expansion effects. Integro-interpolation and iteration finite methods were used for creating their own numerical algorithm. Numerical programs allow solving as direct as inverse gas flow tasks in the cylindrical layer. For verification of inverse task solution, the survey interpretation results from the real gas field were paralleled with currently methods results and showed sufficient accuracy. The described method allows to interpret survey gas hydrodynamic results accounting real gas and porous matrix properties, and well influence to enhance integrity and precision reservoir properties estimation.

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Saremi, M., N. Parsi Benehkohal, C. Dehghanian, and H. R. Zebardast. "Effect of Calcium Gluconate Concentration and Hydrodynamic Effect on Mild Steel Corrosion Inhibition in Simulated Cooling Water." Corrosion 65, no. 12 (December 1, 2009): 778–84. http://dx.doi.org/10.5006/1.3319104.

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Abstract The effects of two important factors, namely concentration and hydrodynamics on the inhibition efficiency of calcium gluconate (C12H22CaO14), were investigated using potentiodynamic polarization and electrochemical impedance spectroscopy tests. Results showed that calcium gluconate was capable of inhibiting the corrosion of mild steel in simulated cooling water. The inhibition efficiency of calcium gluconate was increased by increasing its concentration and decreased by increasing water circulation velocity due to the adsorption process, which leads to the formation of a protective layer with a greater charge-transfer resistance on the metal surface. The hydrodynamic effect seems to promote the adsorption of calcium gluconate on the metal surface, which was confirmed by the fitting of the Langmuir adsorption isotherm.

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Huang, Haocai, Chaowu Sheng, Gang Wu, Yun Shen, and Hangzhou Wang. "Stroke Kinematics Analysis and Hydrodynamic Modeling of a Buoyancy-Supported Water Strider Robot." Applied Sciences 10, no. 18 (September 10, 2020): 6300. http://dx.doi.org/10.3390/app10186300.

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The locomotive ability of a water strider that generates an ellipse-like spatial stroke trajectory when moving is proved to improve its moving efficiency and is seldom imitated by water strider robots. A hydrodynamic analysis can predict the performance of the robots, but research in this area is not enough. A buoyancy-supported water strider robot with the ability of producing an ellipse-like spatial stroke trajectory was designed and analyzed in this study. A semiempirical hydrodynamic model suitable for the buoyancy-supported robot was proposed to study the hydrodynamic characteristics, based on the Newton’s second law of motion. The speed, power and efficiency of the robot were analyzed on the basis of the model which confirmed that the robot performing an ellipse-like spatial stroke trajectory was conducive to its moving efficiency. The experimental results verified that the stroke mechanism produced an ellipse-like spatial trajectory in a practical application and that the robot had good mobility. The proposed hydrodynamic model was validated by comparing the theoretical speed of the robot to the experimental results.

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Wang, Hua, Zilin Shen, Yichuan Zeng, Huaiyu Yan, Yiping Li, and Weihao Yuan. "Connection between Anthropogenic Water Diversion and Hydrodynamic Condition in Plain River Network." Water 13, no. 24 (December 14, 2021): 3596. http://dx.doi.org/10.3390/w13243596.

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The increase in the rate of water renewal driven by hydrodynamics contributes to improving the water quality of the plain river network. Taking the lakeside river network in Wuxi as an example, through numerical simulation, polynomial fitting, correlation analysis, and principal component analysis, the hydrodynamic responses of urban lake-connected river networks to water diversion and hydrodynamic grouping were researched. Based on numerical model and influence weight analysis, we explored the improvement of hydrodynamic conditions of plain river network with strong human intervention and high algal water diversion. The results showed that: (1) The relationship between water diversion impact on river network flow velocity and water diversion flux was not as simple a linear relationship. It could be reflected by polynomial. The water transfer interval in dry season with high hydrodynamic efficiency (HE) was lower than 10 m3/s and higher than 30 m3/s, and the HE increased significantly when the water transfer flow was higher than 20 m3/s in the wet season. (2) According to the main hydrodynamic driving factors, the channels in the river network could be divided into three types: water conservancy projects, river and lake water level difference, and river channel characteristic. The correlations of rivers’ flow velocity in each group were very high. (3) The influence weights of water conservancy projects, river and lake water level difference, and river channel characteristic on the whole river network dynamics were 65, 21, and 12.4%, respectively, and the other factors contributed 1.6% of the weight.

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Sousounis and Shek. "Wave-to-Wire Power Maximization Control for All-Electric Wave Energy Converters with Non-Ideal Power Take-Off." Energies 12, no. 15 (July 31, 2019): 2948. http://dx.doi.org/10.3390/en12152948.

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The research presented in this paper investigates novel ways of optimizing all-electric wave energy converters for maximum wave-to-wire efficiency. In addition, a novel velocity-based controller is presented which was designed specifically for wave-to-wire efficiency maximization. In an ideal wave energy converter system, maximum efficiency in power conversion is achieved by maximizing the hydrodynamic efficiency of the floating body. However, in a real system, that involves losses at different stages from wave to grid, and the global wave-to-wire optimum differs from the hydrodynamic one. For that purpose, a full wave-to-wire wave energy converter that uses a direct-drive permanent magnet linear generator was modelled in detail. The modelling aspect included complex hydrodynamic simulations using Edinburgh Wave Systems Simulation Toolbox and the electrical modelling of the generator, controllers, power converters and the power transmission side with grid connection in MATLAB/Simulink. Three reference controllers were developed based on the previous literature: a real damping, a reactive spring damping and a velocity-based controller. All three literature-based controllers were optimized for maximum wave-to-wire efficiency for a specific wave energy resource profile. The results showed the advantage of using reactive power to bring the velocity of the point absorber and the wave excitation force in phase, which was done directly using the velocity-based controller, achieving higher efficiencies. Furthermore, it was demonstrated that maximizing hydrodynamic energy capture may not lead to maximum wave-to-wire efficiency. Finally, the controllers were also tested in random sea states, and their performance was evaluated.

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Basko, M. M., S. V. Molodtsov, M. V. Sokolovskii, and B. Yu Sharkov. "Hydrodynamic efficiency of energy transfer in experimental targets illuminated with heavy-ion beams." Laser and Particle Beams 11, no. 4 (December 1993): 751–55. http://dx.doi.org/10.1017/s0263034600006480.

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The conditions for an experiment are being discussed in which the hydrodynamic efficiency could be measured and an optimum thermonuclear target design worked out that could be performed on a single-channel accelerator facility producing a 209Bi ion beam of ∼100 GeV per nucleus. As numerical simulations show, the expected values of the hydrodynamic efficiency are 5–10%, while the optimization of the target-beam system could be performed by compressing D-T gas in a conical cavity and registering some 109-1011 neutrons per shot.

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Yang, Chin Ting. "Hydrodynamic Efficiency Improvement of High-Specific-Speed Centrifugal Pump Impeller." Applied Mechanics and Materials 467 (December 2013): 461–65. http://dx.doi.org/10.4028/www.scientific.net/amm.467.461.

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The high-specific-speed centrifugal pumps are very common in industrial factory for transporting fluids all day long. However, oversized pumps with low performance still could meet the purpose of fluid transporting. The aim of this study was to reduce the existed commercial impeller energy consumption by optimizing the performance of impeller through CAE processes. The impeller model was first generated by BladeGen software and analyzed by CFX in Turbo-mode. The optimized model then exported to machine center to cut the precise aluminum mold. A regular sand die casting processes were used to manufacture the impeller. The original pump which only impeller was replaced with the new one was tested with performance measurement system again. The results show that when the mass flow rate between 40-90kg/s the CFD software predicted very well pump heads and efficiencies with experimental data, which was called optimized impeller. But around the minimum and maximum flow rate region, the recirculation flow between blades and frictional loss model used still need further investigation to shrink the difference. Compare to the original impeller, the optimized one had increased efficiency 6% at the mass flow rate of 80kg/s. Also the high efficiency region (nearby of BEP) of the new impeller had broadened 50%. And the maximum mass flow rate increased 13% than the original one.

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Сентябов, А. В., А. А. Гаврилов, М. А. Кривов, А. А. Дектерев, and М. Н. Притула. "Efficiency analysis of hydrodynamic calculations on GPU and CPU clusters." Numerical Methods and Programming (Vychislitel'nye Metody i Programmirovanie), no. 3 (September 20, 2016): 329–38. http://dx.doi.org/10.26089/nummet.v17r331.

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Рассматривается ускорение параллельных гидродинамических расчетов на кластерах с CPU- и GPU-узлами. Для тестирования используется собственный CFD-код SigmaFlow, портированный для расчетов на графических ускорителях с помощью технологии CUDA. Алгоритм моделирования течения несжимаемой жидкости основан на SIMPLE-подобной процедуре и дискретизации с помощью метода контрольного объема на неструктурированных сетках из тексаэдральных ячеек. Сравнение скорости расчета показывает высокую производительность графических ускорителей нового поколения в GPGPU-расчетах. Speedup of parallel hydrodynamic calculations on clusters with CPUs and GPUs is considered. The CFD SigmaFlow code developed by the authors and ported for GPU by means of CUDA is used in test calculations. The incompressible flow simulation is based on a SIMPLE-like procedure and on a discretization by the control volume method on unstructured hexahedral meshes. The performance evaluation shows a high efficiency of the new generation of GPUs for GPGPU calculations.

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Elsafti, Hisham, Hocine Oumeraci, and Hans Scheel. "HYDRODYNAMIC EFFICIENCY AND LOADING OF A TSUNAMI-FLOODING BARRIER (TFB)." Coastal Engineering Proceedings, no. 35 (June 23, 2017): 23. http://dx.doi.org/10.9753/icce.v35.structures.23.

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The Tsunami-Flooding Barrier (TFB) is an impermeable vertical structure proposed at relatively large water depths, at which it is theorised that a tsunami will reach the structure before turning into a bore. The proposed hypothesis is tested in this study by means of a validated Computational Fluid Dynamics (CFD) model. The hydrodynamic efficiency of the impermeable TFB structure is confirmed and the effect of different aspects on the hydrodynamic efficiency of the structure are studied. These aspects include water depth, free board, surface roughness and the consideration of a deflecting parapet (named here as a surge stopper). Further, a new method is developed for calculating the tsunami-like solitary wave run-up and loads on the structure. The method is then compared to the Goda method for calculating storm wave loads on vertical impermeable structures. It is concluded that using the Goda method will severely underestimate the tsunami-like solitary wave load on the TFB structure.

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Shilkin, A., E. Y. Kenig, and Z. Olujic. "Hydrodynamic-analogy-based model for efficiency of structured packing columns." AIChE Journal 52, no. 9 (September 2006): 3055–66. http://dx.doi.org/10.1002/aic.10937.

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Abbasov, A. A., E. M. Abbasov, Sh Z. Ismayilov, and A. A. Suleymanov. "Waterflooding efficiency estimation using capacitance-resistance model with non-linear productivity index." SOCAR Proceedings, no. 3 (September 30, 2021): 45–53. http://dx.doi.org/10.5510/ogp20210300528.

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A modified Capacitive Resistive Model (CRM), with a non-linear Productivity Index (PI), has been suggested to evaluate efficiency of waterflooding in heterogeneous reservoirs. CRM model is based on continuity equation between production and injection, and has several additional advantages. The technique does not require sophisticated geological and hydrodynamics numerical simulation modeling, which would require expensive computing time and based on actual hydrodynamic data. The model adequately describes depletion process and can be used for production forecasting and waterflooding mechanism. Capacitance-resistance model with non-linear productivity index has been tested against numerical model as well as actual production data. Additionally, non-linear productivity index based CRM model was compared against the CRM model with linear productivity index function. The calculations algorithm does not require building static geological models and running dynamic simulations, nor it demands extensive computational resources and time, thanks to using production and injection history only, therefore it can be deployed easily. Keywords: waterflooding; capacitance-resistance model; non-linear productivity index; efficiency; monitoring; forecast.

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Lee, J. H., K. W. Bang, C. S. Choi, and H. S. Lim. "CFD modelling of flow field and particle tracking in a hydrodynamic stormwater separator." Water Science and Technology 62, no. 10 (November 1, 2010): 2381–88. http://dx.doi.org/10.2166/wst.2010.480.

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The best management practices (BMPs) for control of urban stormwater pollution are evaluated to remove solid particles containing various pollutants. Currently, most storm runoff treatment devices using primary pollutant removal mechanism are applied to storm water since most pollutants in runoff are associated with the solid particulates. A hydrodynamic separator is a storm water treatment device using centrifugal motion which separates solids pollution from runoff. In this study, the velocity flow field and particle tracking of hydrodynamic separator were investigated using anthracite as a computational fluid dynamics (CFD) model particle. The Fluent 6.3.26 CFD program was used to predict the solid particles removal efficiency for various parameters such as particle size, surface loading rate, and the ratio of underflow to overflow. The velocity flow field in a hydrodynamic stormwater separator (HDS) has been simulated using CFD RNG κ-ɛ model. Modeling results for the removal efficiency of HDS were similar with the results obtained from experimental measurements of laboratory scale HDS. These results showed that the simulated velocity field was useful to interpret the behavior of flow in the hydrodynamic separator. The results obtained from particle tracking can be applied to predict the separation efficiency.

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Medina Rodríguez, Ayrton Alfonso, Rodolfo Silva Casarín, and Jesús María Blanco Ilzarbe. "A Theoretical Study of the Hydrodynamic Performance of an Asymmetric Fixed-Detached OWC Device." Water 13, no. 19 (September 25, 2021): 2637. http://dx.doi.org/10.3390/w13192637.

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The chamber configuration of an asymmetric, fixed-detached Oscillating Water Column (OWC) device was investigated theoretically to analyze its effects on hydrodynamic performance. Two-dimensional linear wave theory was used, and the solutions for the associated radiation and scattering boundary value problems (BVPs) were derived through the matched eigenfunction expansion method (EEM) and the boundary element method (BEM). The results for the hydrodynamic efficiency and other important hydrodynamic properties were computed and analyzed for various cases. Parameters, such as the length of the chamber and the thickness and submergence of the rear and front walls, were varied. The effects on device performance of adding a step under the OWC chamber and reflecting wall in the downstream region were also investigated. A good agreement between the analytical and numerical results was found. Thinner walls and low submergence of the chamber were seen to increase the efficiency bandwidth. The inclusion of a step slightly reduced the frequency at which resonance occurs, and when a downstream reflecting wall is included, the hydrodynamic efficiency is noticeably reduced at low frequencies due to the near trapped waves in the gap between the OWC device and the rigid vertical wall.

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Lee, D. H., K. S. Min, and J. H. Kang. "Performance evaluation and a sizing method for hydrodynamic separators treating urban stormwater runoff." Water Science and Technology 69, no. 10 (March 13, 2014): 2122–31. http://dx.doi.org/10.2166/wst.2014.125.

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This study reports on 6 years of performance monitoring of stormwater hydrodynamic separators in Korean urban catchments. One hundred and thirty-seven storm events were monitored in four hydrodynamic separators of two different types from 2006 to 2012. Mean values of the event average removal efficiencies of total suspended solids (TSS) for the four hydrodynamic separators were 43.69, 8.54, 42.84, and 14.35% with corresponding mean values of the event average surface overflow rates of 28.62, 40.07, 16.02, and 38.81 m/h, respectively. The low TSS removal efficiency was due to the high instantaneous surface overflow rates frequently occurring throughout a storm event and the abundance of fine particle fractions in the inflow (median particle diameter <75 μm). The Weibull function was used to simulate particle size distribution (PSD) in the runoff and the simulated PSD functions were further applied to the discrete settling theory to develop curves of TSS removal efficiency, as a function of surface overflow rate and median particle size of the inflow. The developed curves should be useful in determining the design peak flow rate and the size of a hydrodynamic separator for a stated goal of TSS removal efficiency.

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Vishnevskij, L. I., and A. R. Togunjac. "Multi-mode adaptive-pitch propeller and its efficiency in coaxial contrarotating propeller systems." Transactions of the Krylov State Research Centre 4, no. 402 (October 14, 2022): 33–40. http://dx.doi.org/10.24937/2542-2324-2022-4-402-33-40.

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Object and purpose of research. This paper discusses possible applications of multi-mode adaptive-pitch propeller in coaxial contra-rotating propeller systems. The study compares efficiency calculation results for these propellers and their conventional FPP counterparts. The authors also give a design calculation layout for coaxial propellers as per hydrodynamic test diagrams for solitary FPPs, as well as demonstrate their hydrodynamic calculation. Calculation results confirm that multimode adaptive-pitch propellers may considerably increase the efficiency of a coaxial propeller system in high-load conditions. The study also demonstrates that coaxial propeller systems have greater efficiency also when they are made up by solitary FPPs. These results might be useful in practical design of various ships. Subject matter and methods. The study relies on hydrodynamic test data for solitary FPPs and gives layouts for design and verification calculations of coaxial propeller systems. Main results. These data could be used to estimate the efficiency of coaxial propulsion for given ship design. Conclusion. The study shows that multi-mode adaptive pitch propeller tend to increase overall efficiency of coaxial propeller systems in high-load conditions as compared to FPPs.

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Phuan, Yi Wen, Eileen Ai Lyn Lau, Harun Mohamed Ismail, Byeong Kyu Lee, and Meng Nan Chong. "Computational Fluid Dynamics Modelling of Photoelectrocatalytic Reactors for the Degradation of Formic Acid." Applied Mechanics and Materials 835 (May 2016): 386–93. http://dx.doi.org/10.4028/www.scientific.net/amm.835.386.

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In this study, computational fluid dynamics (CFD) simulation was used to predict the performance of photoelectrocatalytic (PEC) reactors with surface reactions. PEC process is a promising and sustainable method that is capable for simultaneous organic degradation and hydrogen production. However, the overall PEC process efficiency is still unsatisfactory and not ready for scale-up application. Preliminary study using CFD model can help to reduce development time, money and effort in experimental work while providing comprehensive analysis and optimum PEC reactor design prior to its real physical fabrication. CFD model integrates irradiance distribution, hydrodynamics, species mass transport and chemical reaction kinetics within the reactor. The performance of PEC reactor for organic degradation depends on reactor configurations and hydrodynamic conditions. Thus, the main aim of this study was to optimize different PEC reactor designs using CFD modelling by varying the reactor configurations and hydrodynamic flow conditions for improved efficiency in degrading the sample organic pollutant of formic acid. The CFD modelling showed higher formic acid degradation efficiency for the simulated convex surface photoreactor than the flat surface photoreactor due to the former possess the ability to concentrate the absorbed light onto the photoanode surface. Besides, the CFD modelling showed that the formic acid degradation rate increased with decreasing inlet fluid flow velocity. This was due to the uniform flow distribution that enables evenly coverage of photoanode surface for subsequent degradation of formic acid in the PEC reactors. Further experimental work is required to validate the CFD simulation to allow better understanding and improvement of the overall efficiency of PEC reactors.

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Degtyareva, T. Yu, and R. R. Migmanov. "An integrated approach to evaluating the effectiveness of infill drilling of the Ust-Tegusskoye field." Oil and Gas Studies, no. 5 (October 31, 2021): 140–50. http://dx.doi.org/10.31660/0445-0108-2021-5-140-150.

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The article considers the experience of using infill well patten in the territory of Western Siberia. The justification of geological and geotechnical factors affecting the efficiency of infill drilling with the subsequent use of a sector-crushed hydrodynamic model of the field site is given. With the help of the identified criteria, promising areas of infill drilling of wells are mapped, and it is established that increasing the detail of the grid of the hydrodynamic model makes it possible to clarify the localization of remaining oil in place. Based on the obtained results from the hydrodynamic model, variants of adjusted planned well count are compared according to accumulated and annual indicators. Thus, the infill well drilling program is optimized. The implementation of an integrated approach to the selection of sites for compaction drilling and the use of a detailed hydrodynamic model of this site allows to increase the production efficiency of recoverable remaining oil in place, as well as to level the risks of oil production.

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Van Wassenbergh, Sam, Nuno Zavattieri Potes, and Dominique Adriaens. "Hydrodynamic drag constrains head enlargement for mouthbrooding in cichlids." Journal of The Royal Society Interface 12, no. 109 (August 2015): 20150461. http://dx.doi.org/10.1098/rsif.2015.0461.

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Presumably as an adaptation for mouthbrooding, many cichlid fish species have evolved a prominent sexual dimorphism in the adult head. Since the head of fishes serves as a bow during locomotion, an evolutionary increase in head volume to brood more eggs can trade-off with the hydrodynamic efficiency of swimming. Here, the differences between males and females in three-dimensional shape and size of the external head surfaces and the effect thereof on drag force during locomotion was analysed for the Nile tilapia ( Oreochromis niloticus ), a maternal mouthbrooder. To do so, three-dimensional body surface reconstructions from laser scans and computational fluid dynamics simulations were performed. After scaling the scanned specimens to post-cranial body volume, in order to theoretically equalize propulsive power, the external volume of the head of females was 27% larger than that of males (head length + 14%; head width + 9%). These differences resulted in an approximate 15% increase in drag force. Yet, hydrodynamics imposed important constraints on the adaptation for mouthbrooding as a much more drastic drop in swimming efficiency seems avoided by mainly enlarging the head along the swimming direction.

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Journal articles on the topic 'Hydrodynamic efficiency'

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