Journal articles: 'Fluid-dynamic models'

1

Stringari, S. "Fluid-dynamic models from the Boltzmann equations." Il Nuovo Cimento A 87, no. 2 (May 1985): 231–47. http://dx.doi.org/10.1007/bf02902348.

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Clark, Peter E. "Analysis of fluid loss data II: Models for dynamic fluid loss." Journal of Petroleum Science and Engineering 70, no. 3-4 (February 2010): 191–97. http://dx.doi.org/10.1016/j.petrol.2009.11.010.

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Noh, Yung-Kyun, Jihun Hamm, Frank Chongwoo Park, Byoung-Tak Zhang, and Daniel D. Lee. "Fluid Dynamic Models for Bhattacharyya-Based Discriminant Analysis." IEEE Transactions on Pattern Analysis and Machine Intelligence 40, no. 1 (January 1, 2018): 92–105. http://dx.doi.org/10.1109/tpami.2017.2666148.

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DILLON, R. H., L. J. FAUCI, C. OMOTO, and X. YANG. "Fluid Dynamic Models of Flagellar and Ciliary Beating." Annals of the New York Academy of Sciences 1101, no. 1 (February 15, 2007): 494–505. http://dx.doi.org/10.1196/annals.1389.016.

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Fauci, L., R. Dillon, and X. Yang. "Fluid dynamic models of flagellar and ciliary beating." Journal of Biomechanics 39 (January 2006): S346. http://dx.doi.org/10.1016/s0021-9290(06)84375-7.

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Babovsky, Hans. "Discrete kinetic models in the fluid dynamic limit." Computers & Mathematics with Applications 67, no. 2 (February 2014): 256–71. http://dx.doi.org/10.1016/j.camwa.2013.07.005.

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Mériaux, Catherine, and Claude Jaupart. "Simple fluid dynamic models of volcanic rift zones." Earth and Planetary Science Letters 136, no. 3-4 (December 1995): 223–40. http://dx.doi.org/10.1016/0012-821x(95)00170-h.

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Iida, Hiroyuki, Takeo Nakagawa, and Kristian Spoerer. "Game information dynamic models based on fluid mechanics." Entertainment Computing 3, no. 3 (August 2012): 89–99. http://dx.doi.org/10.1016/j.entcom.2012.04.002.

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Crespo, Antonio. "Computational Fluid Dynamic Models of Wind Turbine Wakes." Energies 16, no. 4 (February 10, 2023): 1772. http://dx.doi.org/10.3390/en16041772.

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Wind energy is one of the main sources of renewable energy that does not contaminate and contributes significantly to the reduction of burning fossil fuels that originate global warming by creating greenhouse gasses; therefore, a significant part the electric energy produced presently is of wind origin, and this share is expected to become more important in the next years [...]

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Colombo, Marco, Roland Rzehak, Michael Fairweather, Yixiang Liao, and Dirk Lucas. "Benchmarking of computational fluid dynamic models for bubbly flows." Nuclear Engineering and Design 375 (April 2021): 111075. http://dx.doi.org/10.1016/j.nucengdes.2021.111075.

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Oh, Chang H., Hyung S. Kang, and Eung S. Kim. "Air-ingress analysis: Part 2—Computational fluid dynamic models." Nuclear Engineering and Design 241, no. 1 (January 2011): 213–25. http://dx.doi.org/10.1016/j.nucengdes.2010.05.065.

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Nie, Zhi Feng, Gang Xie, Yan Qing Hou, Yan Cui, Rong Xing Li, and Zhan Lian Yu. "Fluid Dynamic Simulations on Polysilicon Production." Applied Mechanics and Materials 444-445 (October 2013): 991–95. http://dx.doi.org/10.4028/www.scientific.net/amm.444-445.991.

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Numerical simulations of transport phenomena is one of the valid methods in investigation of crystal silicon growth by CVD for various types of reactors. The present review provides the key summary on the development of fluid dynamic simulations on polysilicon of CVD and hopefully aid in future improvement of this technology. In the solution of CVD reactor models for polysilicon production, the influence of the deposition process on temperature, the transport phenomena and the surface reactions have to be taken into account when discussing the silicon growth rate.

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Dillon, R., Z. Yang, and L. Fauci. "Fluid dynamic models of flagellar and ciliary beating with viscoelasticity." Journal of Biomechanics 39 (January 2006): S346. http://dx.doi.org/10.1016/s0021-9290(06)84377-0.

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Wood, M. G., T. Howes, J. Keller, and M. R. Johns. "Two dimensional computational fluid dynamic models for waste stabilisation ponds." Water Research 32, no. 3 (March 1998): 958–63. http://dx.doi.org/10.1016/s0043-1354(97)00316-3.

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15

Ferguson, T., and R. McGlynn. "Validation of Turbomachinery Computational Fluid Dynamic Models Using Laser Velocimetry." Journal of the IEST 42, no. 6 (November 17, 1999): 19–25. http://dx.doi.org/10.17764/jiet.42.6.y0162422x862g242.

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Computational fluid dynamic (CFD) codes are powerful tools for flow field modeling. The codes, however, must be calibrated with data from actual flows if the predictions of the analysis are to be applied with confidence. Laser velocimetry is one method whereby the predictions of the codes can be anchored with accurate, noninvasive flow-field data. This paper explores the process from initial CFD concerns to the application of the velocimeter in the test facility.

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Strottman, D. "Status of fluid dynamic models for relativistic heavy ion reactions." Nuclear Physics A 566 (January 1994): 245–56. http://dx.doi.org/10.1016/0375-9474(94)90630-0.

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Bonaventura, L., A. Iske, and E. Miglio. "Kernel-based vector field reconstruction in computational fluid dynamic models." International Journal for Numerical Methods in Fluids 66, no. 6 (February 9, 2010): 714–29. http://dx.doi.org/10.1002/fld.2279.

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Chiastra, Claudio, Stefano Morlacchi, Diego Gallo, Umberto Morbiducci, Rubén Cárdenes, Ignacio Larrabide, and Francesco Migliavacca. "Computational fluid dynamic simulations of image-based stented coronary bifurcation models." Journal of The Royal Society Interface 10, no. 84 (July 6, 2013): 20130193. http://dx.doi.org/10.1098/rsif.2013.0193.

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One of the relevant phenomenon associated with in-stent restenosis in coronary arteries is an altered haemodynamics in the stented region. Computational fluid dynamics (CFD) offers the possibility to investigate the haemodynamics at a level of detail not always accessible within experimental techniques. CFD can quantify and correlate the local haemodynamics structures which might lead to in-stent restenosis. The aim of this work is to study the fluid dynamics of realistic stented coronary artery models which replicate the complete clinical procedure of stent implantation. Two cases of pathologic left anterior descending coronary arteries with their bifurcations are reconstructed from computed tomography angiography and conventional coronary angiography images. Results of wall shear stress and relative residence time show that the wall regions more prone to the risk of restenosis are located next to stent struts, to the bifurcations and to the stent overlapping zone for both investigated cases. Considering a bulk flow analysis, helical flow structures are generated by the curvature of the zone upstream from the stent and by the bifurcation regions. Helical recirculating microstructures are also visible downstream from the stent struts. This study demonstrates the feasibility to virtually investigate the haemodynamics of patient-specific coronary bifurcation geometries.

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Coghe, Aldo, Michele Mantegna, and Giorgio Sotgia. "Fluid Dynamic Aspects of Electrostatic Precipatators: Turbulence Characteristics in Scale Models." Journal of Fluids Engineering 125, no. 4 (July 1, 2003): 694–700. http://dx.doi.org/10.1115/1.1593704.

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The present work originated in an investigation on fluid dynamic aspects of electrostatic precipitators performed on scale models of an industrial apparatus. The experimental analysis of velocity and turbulence distribution, performed by hot-wire anemometry, confirmed that significant turbulence levels are found inside particle collectors. In fact, components used to spatially smooth the flow and lower its velocity peaks, such as hoods with wide divergence angles, turning vanes, and perforated plates, may also act as sources of turbulence and reduce the efficiency of electrostatic precipitators. These observations prompted a deeper analysis, both analytical and experimental, of the turbulence decay downstream perforated screens. A new simple semi-empirical model of turbulence decay is proposed, which has shown reasonably good agreement with experimental data, even at short downstream distance from the perforated plate, 50 to 250 hydraulic diameters.

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Bellouquid, Abdelghani, Juan Calvo, Juan Nieto, and Juan Soler. "Hyperbolic versus Parabolic Asymptotics in Kinetic Theory toward Fluid Dynamic Models." SIAM Journal on Applied Mathematics 73, no. 4 (January 2013): 1327–46. http://dx.doi.org/10.1137/120869729.

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Tambasco, Mauro, and David A. Steinman. "Calculating particle-to-wall distances in unstructured computational fluid dynamic models." Applied Mathematical Modelling 25, no. 10 (October 2001): 803–14. http://dx.doi.org/10.1016/s0307-904x(01)00014-2.

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Sego, T. J., Matthew Prideaux, Jane Sterner, Brian Paul McCarthy, Ping Li, Lynda F. Bonewald, Burcin Ekser, Andres Tovar, and Lester Jeshua Smith. "Computational fluid dynamic analysis of bioprinted self‐supporting perfused tissue models." Biotechnology and Bioengineering 117, no. 3 (December 18, 2019): 798–815. http://dx.doi.org/10.1002/bit.27238.

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23

Russell, Jeremy H., Neil Kelson, Mark Barry, Mark Pearcy, David F. Fletcher, and Craig D. Winter. "Computational Fluid Dynamic Analysis of Intracranial Aneurysmal Bleb Formation." Neurosurgery 73, no. 6 (August 13, 2013): 1061–69. http://dx.doi.org/10.1227/neu.0000000000000137.

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Abstract BACKGROUND: The management of unruptured aneurysms is controversial, with the decision to treat influenced by aneurysm characteristics including size and morphology. Aneurysmal bleb formation is thought to be associated with an increased risk of rupture. OBJECTIVE: To correlate computational fluid dynamic (CFD) indices with bleb formation. METHODS: Anatomic models were constructed from 3-dimensional rotational angiography data in 27 patients with cerebral aneurysms harboring a single bleb. Additional models representing the aneurysm before bleb formation were constructed by digitally removing the bleb. We characterized hemodynamic features of models both with and without the blebs using CFDs. Flow structure, wall shear stress (WSS), pressure, and oscillatory shear index (OSI) were analyzed. RESULTS: There was a statistically significant association between bleb location at or adjacent to the point of maximal WSS (74%, P = .019), irrespective of rupture status. Aneurysmal blebs were related to the inflow or outflow jet in 89% of cases (P < .001), whereas 11% were unrelated. Maximal wall pressure and OSI were not significantly related to bleb location. The bleb region attained a lower WSS after its formation in 96% of cases (P < .001) and was also lower than the average aneurysm WSS in 86% of cases (P < .001). CONCLUSION: Cerebral aneurysm blebs generally form at or adjacent to the point of maximal WSS and are aligned with major flow structures. Wall pressure and OSI do not contribute to determining bleb location. The measurement of WSS using CFD models may potentially predict bleb formation and thus improve the assessment of rupture risk in unruptured aneurysms.

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Sunada, S., H. Takashima, T. Hattori, K. Yasuda, and K. Kawachi. "Fluid-dynamic characteristics of a bristled wing." Journal of Experimental Biology 205, no. 17 (September 1, 2002): 2737–44. http://dx.doi.org/10.1242/jeb.205.17.2737.

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SUMMARYThrips fly at a chord-based Reynolds number of approximately 10 using bristled rather than solid wings. We tested two dynamically scaled mechanical models of a thrips forewing. In the bristled design, cylindrical rods model the bristles of the forewing; the solid design was identical to the bristled one in shape, but the spaces between the `bristles' were filled in by membrane. We studied four different motion patterns: (i) forward motion at a constant forward velocity, (ii) forward motion at a translational acceleration, (iii) rotational motion at a constant angular velocity and (iv)rotational motion at an angular acceleration. Fluid-dynamic forces acting on the bristled model wing were a little smaller than those on the solid wing. Therefore, the bristled wing of a thrips cannot be explained in terms of increased fluid-dynamic forces.

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Margolis, D. L., and W. C. Yang. "Bond Graph Models for Fluid Networks Using Modal Approximation." Journal of Dynamic Systems, Measurement, and Control 107, no. 3 (September 1, 1985): 169–75. http://dx.doi.org/10.1115/1.3140716.

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Modal bond graph representations of the dissipative model of rigid, cylindrical fluid transmission lines with laminar flow are developed. Modal approximation techniques are used for both hydraulic and pneumatic lines. The modeling and simulation procedures for fluid networks coupled with nonlinear and dynamic systems are greatly facilitated using bond graphs. The physical interpretation of the model is preserved in this approach. Simulation results for hydraulic single lines are compared with results derived by the quasi-method of characteristics. The simulation results for fluid networds for various line and termination configurations are illustrated.

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Hong, Se-woon, Jinseon Park, Hanna Jeong, Seyeon Lee, Lakyeong Choi, Lingying Zhao, and Heping Zhu. "Fluid Dynamic Approaches for Prediction of Spray Drift from Ground Pesticide Applications: A Review." Agronomy 11, no. 6 (June 10, 2021): 1182. http://dx.doi.org/10.3390/agronomy11061182.

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Spray drifts have been studied by mathematical models and computer simulations as an essential complement to lab and field tests, among which are fluid dynamic approaches that help to understand the transport of spray droplets in a turbulent atmosphere and their potential impacts to the environment. From earlier fluid mechanical models to highly computational models, scientific advancement has led to a more realistic prediction of spray drift, but the current literature lacks reviews showing the trends and limitations of the existing approaches. This paper is to review the literature on fluid-mechanical-based modelling of spray drift resulting from ground spray applications. Consequently, it provides comprehensive understanding of the transition and development of fluid dynamic approaches and the future directions in this research field.

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Costello, M., and J. Sahu. "Using computational fluid dynamic/rigid body dynamic results to generate aerodynamic models for projectile flight simulation." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 222, no. 7 (July 2008): 1067–79. http://dx.doi.org/10.1243/09544100jaero304.

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Hu, Shao Qing, and Bai Tao Sun. "Dynamic Responses of Arch Dams Considering Different Reservoir Models." Advanced Materials Research 250-253 (May 2011): 3923–26. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.3923.

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In this paper, the dynamic responses of an arch dam in the case of normal water level and operating low water level were simulated by using additional mass model and incompressible finite element model for reservoir respectively. The results showed that the reservoir models have a great impact on dynamic response of arch dams. The maximum principle tensile stress using incompressible finite element model of fluid is less than that using additional mass model. With the depth of the reservoir water increasing, the hydrodynamic pressure acting ton the dam surface caused by earthquake force increased and the dynamic responses of dam also increased.

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Bennett, James S., Charles E. Feigley, Jamil Khan, and Mohamed H. Hosni. "Comparison of Mathematical Models for Exposure Assessment With Computational Fluid Dynamic Simulation." Applied Occupational and Environmental Hygiene 15, no. 1 (January 2000): 131–44. http://dx.doi.org/10.1080/104732200301953.

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Cardin, Franco, and Claudio Tebaldi. "Finite reductions for dissipative systems and viscous fluid-dynamic models on T2." Journal of Mathematical Analysis and Applications 345, no. 1 (September 2008): 213–22. http://dx.doi.org/10.1016/j.jmaa.2008.04.012.

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Fumero, Roberto, and Riccardo Pietrabissa. "Fluid dynamic models as a guide to determine prosthetic heart valve diameter." Journal of Biomechanics 19, no. 1 (January 1986): 71–77. http://dx.doi.org/10.1016/0021-9290(86)90110-7.

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Tambasco, Mauro, and David A. Steinman. "On Assessing the Quality of Particle Tracking Through Computational Fluid Dynamic Models." Journal of Biomechanical Engineering 124, no. 2 (March 29, 2002): 166–75. http://dx.doi.org/10.1115/1.1449489.

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Quantification of particle deposition patterns, transit times, and shear exposure is important for computational fluid dynamic (CFD) studies involving respiratory and arterial models. To numerically compute such path-dependent quantities, it is necessary to employ a Lagrangian approach where particles are tracked through a pre-computed velocity field. However, it is difficult to determine in advance whether a particular velocity field is sufficiently resolved for the purposes of tracking particles accurately. Towards this end, we propose the use of volumetric residence time (VRT)—previously defined for 2-D studies of platelet activation and here extended to more physiologically relevant 3-D models—as a means of quantifying whether a volume of Lagrangian fluid elements (LFE’s) seeded uniformly and contiguously at the model inlet remains uniform throughout the flow domain. Such “Lagrangian mass conservation” is shown to be satisfied when VRT=1 throughout the model domain. To demonstrate this novel concept, we computed maps of VRT and particle deposition in 3-D steady flow models of a stenosed carotid bifurcation constructed with one adaptively refined and three nominally uniform finite element meshes of increasing element density. A key finding was that uniform VRT could not be achieved for even the most resolved meshes and densest LFE seeding, suggesting that care should be taken when extracting quantitative information about path-dependent quantities. The VRT maps were found to be useful for identifying regions of a mesh that were under-resolved for such Lagrangian studies, and for guiding the construction of more adequately resolved meshes.

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Skoglund, Tomas, Karl-Erik Årzén, and Petr Dejmek. "Dynamic object-oriented heat exchanger models for simulation of fluid property transitions." International Journal of Heat and Mass Transfer 49, no. 13-14 (July 2006): 2291–303. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2005.12.005.

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Thomas, John H. "Fluid dynamics of cerebrospinal fluid flow in perivascular spaces." Journal of The Royal Society Interface 16, no. 159 (October 23, 2019): 20190572. http://dx.doi.org/10.1098/rsif.2019.0572.

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The flow of cerebrospinal fluid along perivascular spaces (PVSs) is an important part of the brain’s system for delivering nutrients and eliminating metabolic waste products (such as amyloid-β); it also offers a pathway for the delivery of therapeutic drugs to the brain parenchyma. Recent experimental results have resolved several important questions about this flow, setting the stage for advances in our understanding of its fluid dynamics. This review summarizes the new experimental evidence and provides a critical evaluation of previous fluid-dynamic models of flows in PVSs. The review also discusses some basic fluid-dynamic concepts relevant to these flows, including the combined effects of diffusion and advection in clearing solutes from the brain.

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De, Sudipto K., and N. R. Aluru. "Coupling of hierarchical fluid models with electrostatic and mechanical models for the dynamic analysis of MEMS." Journal of Micromechanics and Microengineering 16, no. 8 (July 18, 2006): 1705–19. http://dx.doi.org/10.1088/0960-1317/16/8/036.

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Fredette, Luke, Siddharth Rath, and Rajendra Singh. "Nonlinear fluid damping models for hydraulic bushing under sinusoidal or transient excitation." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 233, no. 3 (January 29, 2018): 595–604. http://dx.doi.org/10.1177/0954407017751787.

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Hydraulic bushings are typically characterized in terms of sinusoidal dynamic stiffness at lower frequencies over a range of excitation amplitudes. However, in practice they are also exposed to severe transient loads in conjunction with sinusoidal excitations. Three improved nonlinear, lumped parameter models for hydraulic bushings are developed with the goal of concurrently predicting amplitude-sensitive dynamic responses to both sinusoidal and step-like excitations using a common dynamic model with the same parameters. First, a fluid resistance element is introduced which extends previous formulations by relaxing the assumption of fully developed turbulent flow, and capturing the transition from laminar flow to turbulence. Second, a bleed orifice element between the two compliance chambers is incorporated to simulate leakage observed in laboratory testing. The sensitivity of the dynamic responses to linearized model parameters is used to guide the parameter identification procedure. Measured dynamic stiffness spectra and step-like responses provide experimental validation of the proposed formulations. The new formulations achieve improved predictions of dynamic stiffness or force using exactly the same set of model parameters at several excitation amplitudes in both time and frequency domains.

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Hua, Xiaoqing, Joelle Frechette, and Michael A. Bevan. "Nanoparticle adsorption dynamics at fluid interfaces." Soft Matter 14, no. 19 (2018): 3818–28. http://dx.doi.org/10.1039/c8sm00273h.

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Dalla Vedova, Matteo D. L., and Pier Carlo Berri. "Proposal of a new simplified fluid dynamic model for aerospace servovalves." MATEC Web of Conferences 304 (2019): 04014. http://dx.doi.org/10.1051/matecconf/201930404014.

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Highly detailed computer models are required for design and development of modern flight control systems, capable of emulating with high accuracy the behaviour of on-board equipment. At the same time, different simplified models are needed, specifically intended for operations such as the optimization of preliminary design and the development of diagnostic or prognostic strategies. These simplified models are required to combine sufficient levels of accuracy and reliability with reduced computational costs, to minimize the computational burden associated with prognostic and optimization algorithms. In this work, we focus on electro-hydraulic actuators, since they are critical subsystems in terms of safety and availability of the aircraft. Advanced monitoring and prognostic algorithms require new numerical models, combining an acceptable computational effort with a satisfying ability to simulate their performance and dynamics. To this purpose, this paper proposes a new simplified numerical model of the servovalve fluid-dynamic behaviour. This numerical algorithm, based on a very compact semi-empirical formulation, is intended to take into account in a simplified but sufficiently accurate way several typical effects related to the SV spool geometry and the operating conditions. To evaluate the approximations introduced by this model into a system-level simulation, it has been integrated into a dedicated numerical model simulating a simple electrohydraulic on-board actuator, and compared with a higher fidelity servovalve model.

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Hanspal, Navraj S., Babatunde A. Allison, Lipika Deka, and Diganta B. Das. "Artificial neural network (ANN) modeling of dynamic effects on two-phase flow in homogenous porous media." Journal of Hydroinformatics 15, no. 2 (November 16, 2012): 540–54. http://dx.doi.org/10.2166/hydro.2012.119.

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The dynamic effect in two-phase flow in porous media indicated by a dynamic coefficient τ depends on a number of factors (e.g. medium and fluid properties). Varying these parameters parametrically in mathematical models to compute τ incurs significant time and computational costs. To circumvent this issue, we present an artificial neural network (ANN)-based technique for predicting τ over a range of physical parameters of porous media and fluid that affect the flow. The data employed for training the ANN algorithm have been acquired from previous modeling studies. It is observed that ANN modeling can appropriately characterize the relationship between the changes in the media and fluid properties, thereby ensuring a reliable prediction of the dynamic coefficient as a function of water saturation. Our results indicate that a double-hidden-layer ANN network performs better in comparison to the single-hidden-layer ANN models for the majority of the performance tests carried out. While single-hidden-layer ANN models can reliably predict complex dynamic coefficients (e.g. water saturation relationships) at high water saturation content, the double-hidden-layer neural network model outperforms at low water saturation content. In all the cases, the single- and double-hidden-layer ANN models are better predictors in comparison to the regression models attempted in this work.

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Zhai, Hong Bo, Jian Jun Su, Xiao Min Yan, and Wei Liu. "Dynamic Response of the Pipe Conveying Fluid with the Pressure Pulsation." Advanced Materials Research 1094 (March 2015): 491–94. http://dx.doi.org/10.4028/www.scientific.net/amr.1094.491.

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The dynamic response characteristic of the pipe conveying fluid was researched with the fluid pressure pulsation in this article. For some hydraulic power pipe system, formed the mathematic models and the transfer matrices of the main hydraulic elements based on the fluid network algorithm, deduced the calculation formulae of input-output pressure pulsation, gained the transitive relationship of the fluid flow pulsation and pressure pulsation, and then studied the pressure pulsation amplitude of the hydraulic power pipes with different working pressures. This study, which analyzed the dynamic response of the pipe conveying fluid and discussed the feasibility of increasing the working pressure, is valuable for the design and the application of the pipes conveying fluid.

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de Avillez, M. A., D. Breitschwerdt, A. Asgekar, and E. Spitoni. "ISM simulations: an overview of models." Proceedings of the International Astronomical Union 10, H16 (August 2012): 606–8. http://dx.doi.org/10.1017/s1743921314012393.

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AbstractUntil recently the dynamical evolution of the interstellar medium (ISM) was simulated using collisional ionization equilibrium (CIE) conditions. However, the ISM is a dynamical system, in which the plasma is naturally driven out of equilibrium due to atomic and dynamic processes operating on different timescales. A step forward in the field comprises a multi-fluid approach taking into account the joint thermal and dynamical evolutions of the ISM gas.

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Muszynska, A. "Improvements in Lightly Loaded Rotor/Bearing and Rotor/Seal Models." Journal of Vibration and Acoustics 110, no. 2 (April 1, 1988): 129–36. http://dx.doi.org/10.1115/1.3269489.

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A model for lightly loaded steadily rotating shaft/bearing/seal systems is proposed in this paper. The model is based on modal characteristics for the rotor, and rotational characteristics for the fluid dynamic forces generated in bearings and/or seals. The fluid average circumferential velocity ratio as a nonlinear function of shaft eccentricity represents a key factor in the model. The model is extremely useful for rotor stability analysis. The model adequacy was proved for one and two lateral mode models of rotors.

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Zamponi, Nicola. "Some fluid-dynamic models for quantum electron transport in graphene via entropy minimization." Kinetic & Related Models 5, no. 1 (2012): 203–21. http://dx.doi.org/10.3934/krm.2012.5.203.

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Simão, M., J. Mora-Rodriguez, and H. M. Ramos. "Computational dynamic models and experiments in the fluid–structure interaction of pipe systems." Canadian Journal of Civil Engineering 43, no. 1 (January 2016): 60–72. http://dx.doi.org/10.1139/cjce-2015-0253.

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Fluid–structure interaction is analyzed using 1D and 3D computational models and results from an experimental facility, where transient events are induced. The water-hammer phenomenon is modelled by a 1D model based on the method of characteristics and the COMSOL Multiphysics 4.3b, which uses finite element method to study the fluid structural interaction involved in a long pressurized pipe system with curves, expansion joints, anchor and support blocks and different rheological behaviour of the pipe material. Comparisons are made between the experimental data and the two numerical models, where the type of response of each model was enhanced, as well as the ability of each model to simulate real conditions.

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Singh, Narinder Pal, and Kiao Inthavong. "Can computational fluid dynamic models help us in the treatment of chronic rhinosinusitis." Current Opinion in Otolaryngology & Head & Neck Surgery 29, no. 1 (December 10, 2020): 21–26. http://dx.doi.org/10.1097/moo.0000000000000682.

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Kladeková, Daniela, Renáta Oriňáková, Hans-Dieter Wiemhöfer, Annamária Krajníková, and Andrej Oriňák. "Computational Fluid Dynamic Modeling of a Mixing Stirred Reactor: Three-Dimensional Axisymmetric Models." Particulate Science and Technology 31, no. 2 (March 2013): 147–55. http://dx.doi.org/10.1080/02726351.2012.675015.

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47

Esteki, Kambiz, Ashutosh Bagchi, and Ramin Sedaghati. "Dynamic analysis of electro- and magneto-rheological fluid dampers using duct flow models." Smart Materials and Structures 23, no. 3 (February 14, 2014): 035016. http://dx.doi.org/10.1088/0964-1726/23/3/035016.

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Deng, Yulin, Qingkang Guo, Yasir Ibrahim Shah, and Lueqin Xu. "Study on Modal Dynamic Response and Hydrodynamic Added Mass of Water-Surrounded Hollow Bridge Pier with Pile Foundation." Advances in Civil Engineering 2019 (January 6, 2019): 1–23. http://dx.doi.org/10.1155/2019/1562753.

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This article presents an experiment program conducted to study the modal dynamic response of hollow bridge pier with pile foundation submerged in water. The forced vibration method was applied on a specimen designated with four levels of tip mass; and the dynamic characteristics of the first four lateral vibration modes of the specimen, including the first two modes along the x-axis and the first two modes along the y-axis, were tested for three different cases where the specimen contacts with only outer water, only inner water, and both outer and inner water, respectively. Finite element models were established using potential-based fluid elements in accordance with the three different cases. The effects of fluid-structure interaction on the dynamic characteristics of the first four lateral modes of the specimen were then investigated through numerical simulations, and the finite element models were verified by validating numerical results against the experimental data. Based on the verified models, hydrodynamic added mass (HAM) and modal hydrodynamic added mass (MHAM) along the x-axis and y-axis of the specimen, induced by fluid-structure interaction, were studied with respect to the three cases. According to the distribution of modal acceleration and hydrodynamic pressure along the pier body, hydrodynamic added mass (HAM) distribution along the pier body was analyzed, and a simplified analytical model which equals the original fluid-structure numerical model was proposed to determine the dynamic characteristics of hollow bridge piers submerged in water. The research provides a better understanding of the effect of fluid-structure interaction on the modal dynamic response of deep-water bridges with hollow piers.

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Zhang, Li Na, and Su Zhen Wang. "Analysis on Fluid-Structure Interaction Dynamic Characteristics of Steam Generator Heat Exchanger Tubes." Advanced Materials Research 382 (November 2011): 52–55. http://dx.doi.org/10.4028/www.scientific.net/amr.382.52.

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The fluid-structure interaction (FSI) dynamic characteristics of steam generator tubes counting for much with safety of an operating nuclear power plants are investigated by analytical methods based on dynamics mechanics and FSI theories. By using the parametric design language APDL of finite element program ANSYS, intelligently dividing model, setting up material and geometric parameters, the models of tubes with internal and external fluid, the different factors influencing on fluid-structure interaction dynamic characteristics of steam generator tubes are investigated by numerical method.

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McClure, J. E., M. A. Berrill, W. G. Gray, and C. T. Miller. "Tracking interface and common curve dynamics for two-fluid flow in porous media." Journal of Fluid Mechanics 796 (April 29, 2016): 211–32. http://dx.doi.org/10.1017/jfm.2016.212.

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The movements of fluid–fluid interfaces and the common curve are an important aspect of two-fluid-phase flow through porous media. The focus of this work is to develop, apply and evaluate methods to simulate two-fluid-phase flow in porous medium systems at the microscale and to demonstrate how these results can be used to support evolving macroscale models. Of particular concern is the problem of spurious velocities that confound the accurate representation of interfacial dynamics in such systems. To circumvent this problem, a combined level-set and lattice-Boltzmann method is advanced to simulate and track the dynamics of the fluid–fluid interface and of the common curve during simulations of two-fluid-phase flow in porous media. We demonstrate that the interface and common curve velocities can be determined accurately, even when spurious currents are generated in the vicinity of interfaces. Static and dynamic contact angles are computed and shown to agree with existing slip models. A resolution study is presented for dynamic drainage and imbibition in a sphere pack, demonstrating the sensitivity of averaged quantities to resolution.

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Journal articles on the topic 'Fluid-dynamic models'

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