Статті в журналах: "Multiphase Flow Solver"

1

Lin, Zhipeng, Wenjing Yang, Houcun Zhou, Xinhai Xu, Liaoyuan Sun, Yongjun Zhang, and Yuhua Tang. "Communication Optimization for Multiphase Flow Solver in the Library of OpenFOAM." Water 10, no. 10 (October 16, 2018): 1461. http://dx.doi.org/10.3390/w10101461.

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Multiphase flow solvers are widely-used applications in OpenFOAM, whose scalability suffers from the costly communication overhead. Therefore, we establish communication-optimized multiphase flow solvers in OpenFOAM. In this paper, we first deliver a scalability bottleneck test on the typical multiphase flow case damBreak and reveal that the Message Passing Interface (MPI) communication in a Multidimensional Universal Limiter for Explicit Solution (MULES) and a Preconditioned Conjugate Gradient (PCG) algorithm is the short slab of multiphase flow solvers. Furthermore, an analysis of the communication behavior is carried out. We find that the redundant communication in MULES and the global synchronization in PCG are the performance limiting factors. Based on the analysis, we propose our communication optimization algorithm. For MULES, we remove the redundant communication and obtain optMULES. For PCG, we import several intermediate variables and rearrange PCG to reduce the global communication. We also overlap the computation of matrix-vector multiply and vector update with the non-blocking computation. The resulting algorithms are respectively referred to as OFPiPePCG and OFRePiPePCG. Extensive experiments show that our proposed method could dramatically increase the parallel scalability and solving speed of multiphase flow solvers in OpenFOAM approximately without the loss of accuracy.

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2

Nguyen, Viet-Bac, Quoc-Vu Do, and Van-Sang Pham. "An OpenFOAM solver for multiphase and turbulent flow." Physics of Fluids 32, no. 4 (April 1, 2020): 043303. http://dx.doi.org/10.1063/1.5145051.

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3

Ivanov, E. A., A. S. Klyuyev, A. A. Zharkovskii, and I. O. Borshchev. "Numerical Simulation of Multiphase Flow Structures in Openfoam Software Package." E3S Web of Conferences 320 (2021): 04016. http://dx.doi.org/10.1051/e3sconf/202132004016.

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Numerical simulation of various structures of multiphase flow in the pipe was performed using the OpenFOAM software package. A visual comparison of multiphase flow design structures for separated stratified-wave, plug and annular flow modes with experimental data is presented. For multiphase flow modelling the solver compressibleInterFoam was used. From the results of numerical modelling, it follows that the OpenFOAM software package allows correct prediction of multiphase flow modes in the pipe depending on Reynolds numbers for gas and liquid phases of the flow.

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4

Li, Wei, and Mathieu Desbrun. "Fluid-Solid Coupling in Kinetic Two-Phase Flow Simulation." ACM Transactions on Graphics 42, no. 4 (July 26, 2023): 1–14. http://dx.doi.org/10.1145/3592138.

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Real-life flows exhibit complex and visually appealing behaviors such as bubbling, splashing, glugging and wetting that simulation techniques in graphics have attempted to capture for years. While early approaches were not capable of reproducing multiphase flow phenomena due to their excessive numerical viscosity and low accuracy, kinetic solvers based on the lattice Boltzmann method have recently demonstrated the ability to simulate water-air interaction at high Reynolds numbers in a massively-parallel fashion. However, robust and accurate handling of fluid-solid coupling has remained elusive: be it for CG or CFD solvers, as soon as the motion of immersed objects is too fast or too sudden, pressures near boundaries and interfacial forces exhibit spurious oscillations leading to blowups. Built upon a phase-field and velocity-distribution based lattice-Boltzmann solver for multiphase flows, this paper spells out a series of numerical improvements in momentum exchange, interfacial forces, and two-way coupling to drastically reduce these typical artifacts, thus significantly expanding the types of fluid-solid coupling that we can efficiently simulate. We highlight the numerical benefits of our solver through various challenging simulation results, including comparisons to previous work and real footage.

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5

Chen, Guo-Qing, Hongyuan Li, Pengyu Lv, and Huiling Duan. "An improved multiphase lattice Boltzmann flux solver with phase interface compression for incompressible multiphase flows." Physics of Fluids 35, no. 1 (January 2023): 013310. http://dx.doi.org/10.1063/5.0131506.

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Numerical dissipation is ubiquitous in multiphase flow simulation. This paper introduces a phase interface compression term into the recently developed multiphase lattice Boltzmann flux solver and achieves an excellent interface maintenance. Here, the phase interface compression term only works in the interface region and is solved as the flux in finite volume discretization. At each cell interface, the interfacial compression velocity [Formula: see text] is determined by local reconstruction velocities of the multiphase lattice Boltzmann flux solver, which maintains the consistency of the flux evaluation. Meanwhile, the interfacial order parameter C in the phase interface compression term is obtained by the second order upwind scheme according to the interface normal direction. Numerical validation of the present model has been made by simulating the Zalesak problem, the single vortex problem, Rayleigh–Taylor instability, and bubble rising and coalescence. The obtained results indicate the validity and reliability of the present model.

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6

Guo, Yisen, and Yongsheng Lian. "Calculation of Water Collection Efficiency Using a Multiphase Flow Solver." Journal of Aircraft 56, no. 2 (March 2019): 685–94. http://dx.doi.org/10.2514/1.c034793.

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7

Singh, Gurpreet, Gergina Pencheva, and Mary F. Wheeler. "An approximate Jacobian nonlinear solver for multiphase flow and transport." Journal of Computational Physics 375 (December 2018): 337–51. http://dx.doi.org/10.1016/j.jcp.2018.08.043.

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8

Jiang, LiJuan, HongGuang Sun, and Yan Wang. "Modeling immiscible fluid flow in fractal pore medium by multiphase lattice Boltzmann flux solver." Physics of Fluids 35, no. 2 (February 2023): 023334. http://dx.doi.org/10.1063/5.0137360.

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In this paper, the multiphase lattice Boltzmann flux solver (MLBFS), where the phase field model and the apparent liquid permeability model are built-in, is developed to simulate incompressible multiphase flows in fractal pore structure at the representative elementary volume scale. MLBFS takes advantage of the traditional Navier–Stokes solver (e.g., geometric flexibility and direct handling of complex boundary conditions) and lattice Boltzmann method (e.g., intrinsically kinetic nature, simplicity, and parallelism). It is easily applied to simulate multiphase flows transport in the porous medium with large density ratios and high Reynolds numbers. This study focuses on the fluid flow in fractal pore structures and provides an in-depth discussion of the effects of non-Newtonian index, fractal parameters, and density ratios on multiphase flow. The proposed model is validated with benchmark problems to test the applicability and reliability of the MLBFS in describing fluid flow in fractal pore structures with large density ratios and viscosity ratios. Simulation results show that the fractal parameters (i.e., fractal dimension, tortuous fractal dimension, porosity, and capillary radius ratio) can accurately characterize fractal pore structure and significantly affect the apparent liquid permeability. In addition, the flow rate increases with the fractal dimension and decreases with the tortuous fractal dimension, while both flow rate and apparent liquid permeability decrease as the capillary radius ratio. It is also noteworthy that the effect of nonlinear drag forces cannot be neglected for shear-thickened flows.

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9

Abas, Aizat, N. Hafizah Mokhtar, M. H. H. Ishak, M. Z. Abdullah, and Ang Ho Tian. "Lattice Boltzmann Model of 3D Multiphase Flow in Artery Bifurcation Aneurysm Problem." Computational and Mathematical Methods in Medicine 2016 (2016): 1–17. http://dx.doi.org/10.1155/2016/6143126.

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This paper simulates and predicts the laminar flow inside the 3D aneurysm geometry, since the hemodynamic situation in the blood vessels is difficult to determine and visualize using standard imaging techniques, for example, magnetic resonance imaging (MRI). Three different types of Lattice Boltzmann (LB) models are computed, namely, single relaxation time (SRT), multiple relaxation time (MRT), and regularized BGK models. The results obtained using these different versions of the LB-based code will then be validated with ANSYS FLUENT, a commercially available finite volume- (FV-) based CFD solver. The simulated flow profiles that include velocity, pressure, and wall shear stress (WSS) are then compared between the two solvers. The predicted outcomes show that all the LB models are comparable and in good agreement with the FVM solver for complex blood flow simulation. The findings also show minor differences in their WSS profiles. The performance of the parallel implementation for each solver is also included and discussed in this paper. In terms of parallelization, it was shown that LBM-based code performed better in terms of the computation time required.

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10

Zhou, Houcun, Min Xiang, Shiwei Zhao, and Weihua Zhang. "Development of a multiphase solver for cavitation flow near free surface." Ocean Engineering 188 (September 2019): 106236. http://dx.doi.org/10.1016/j.oceaneng.2019.106236.

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11

Ma, Z. H., L. Qian, P. J. Martínez-Ferrer, D. M. Causon, C. G. Mingham, and W. Bai. "An overset mesh based multiphase flow solver for water entry problems." Computers & Fluids 172 (August 2018): 689–705. http://dx.doi.org/10.1016/j.compfluid.2018.01.025.

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12

Ouazzi, A., S. Turek, and H. Damanik. "A curvature-free multiphase flow solver via surface stress-based formulation." International Journal for Numerical Methods in Fluids 88, no. 1 (April 25, 2018): 18–31. http://dx.doi.org/10.1002/fld.4509.

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13

Shonibare, Olabanji Y., and Kent E. Wardle. "Numerical Investigation of Vertical Plunging Jet Using a Hybrid Multifluid–VOF Multiphase CFD Solver." International Journal of Chemical Engineering 2015 (2015): 1–14. http://dx.doi.org/10.1155/2015/925639.

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A novel hybrid multiphase flow solver has been used to conduct simulations of a vertical plunging liquid jet. This solver combines a multifluid methodology with selective interface sharpening to enable simulation of both the initial jet impingement and the long-time entrained bubble plume phenomena. Models are implemented for variable bubble size capturing and dynamic switching of interface sharpened regions to capture transitions between the initially fully segregated flow types into the dispersed bubbly flow regime. It was found that the solver was able to capture the salient features of the flow phenomena under study and areas for quantitative improvement have been explored and identified. In particular, a population balance approach is employed and detailed calibration of the underlying models with experimental data is required to enable quantitative prediction of bubble size and distribution to capture the transition between segregated and dispersed flow types with greater fidelity.

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14

Miao, Sha, Kelli Hendrickson, and Yuming Liu. "Computation of three-dimensional multiphase flow dynamics by Fully-Coupled Immersed Flow (FCIF) solver." Journal of Computational Physics 350 (December 2017): 97–116. http://dx.doi.org/10.1016/j.jcp.2017.08.042.

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15

Joubert, Johannes C., Daniel N. Wilke, and Patrick Pizette. "A Generalized Finite Difference Scheme for Multiphase Flow." Mathematical and Computational Applications 28, no. 2 (March 26, 2023): 51. http://dx.doi.org/10.3390/mca28020051.

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This paper presents a GPU-based, incompressible, multiphase generalized finite difference solver for simulating multiphase flow. The method includes a dampening scheme that allows for large density ratio cases to be simulated. Two verification studies are performed by simulating the relaxation of a square droplet surrounded by a light fluid and a bubble rising in a denser fluid. The scheme is also used to simulate the collision of binary droplets at moderate Reynolds numbers (250–550). The effects of the surface tension and density ratio are explored in this work by considering cases with Weber numbers of 8 and 180 and density ratios of 2:1 and 1000:1. The robustness of the multiphase scheme is highlighted when resolving thin fluid structures arising in both high and low density ratio cases at We = 180.

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16

Behrangi, Farhang, Mohammad Ali Banihashemi, Masoud Montazeri Namin, and Asghar Bohluly. "FGA-MMF method for the simulation of two-phase flows." Engineering Computations 35, no. 3 (May 8, 2018): 1161–82. http://dx.doi.org/10.1108/ec-03-2017-0076.

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Purpose This paper aims to present a novel numerical technique for solving the incompressible multiphase mixture model. Design/methodology/approach The multiphase mixture model contains a set of momentum and continuity equations for the mixture phase, a second phase continuity equation and the algebraic equation for the relative velocity. For solving continuity equation for the second phase and advection term of momentum, an improved approach fine grid advection-multiphase mixture flow (FGA-MMF) is developed. In the FGA-MMF method, the continuity equation for the second phase is solved with higher-order schemes in a two times finer grid. To solve the advection term of the momentum equation, the advection fluxes of the volume fraction in the continuity equation for the second phase are used. Findings This approach has been used in various tests to simulate unsteady flow problems. Comparison between numerical results and experimental data demonstrates a satisfactory performance. Numerical examples show that this approach increases the accuracy and stability of the solution and decreases non-monotonic results. Research limitations/implications The solver for the multi-phase mixture model can only be adopted to solve the incompressible fluid flow. Originality/value The paper developed an innovative solution (FGA-MMF) to find multi-phase flow field value in the multi-phase mixture model. Advantages of the FGA-MMF technique are the ability to accurately determine the phases interpenetrating, decreasing the numerical diffusion of the interface and preventing instability and non-monotonicity in solution of large density variation problems.

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17

Reddy, Rajesh, and R. Banerjee. "GPU accelerated VOF based multiphase flow solver and its application to sprays." Computers & Fluids 117 (August 2015): 287–303. http://dx.doi.org/10.1016/j.compfluid.2015.05.013.

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18

Mu, Li Li, and Ning Xue. "Numerical Simulation of Micro Flow Field of Micro Injector." Advanced Materials Research 327 (September 2011): 61–65. http://dx.doi.org/10.4028/www.scientific.net/amr.327.61.

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In order to research the effects of digital micro droplet injected by the piezoelectric ceramic inertial driver, the calculation model of micro flow field of micro injector was established based on the VOF model of multiphase flow. The calculation selected the implicit segregated solver and the standard k-e model was used in turbulence of the micro-nozzle. The governing equation was separated in first order upwind, and solved by PISO algorithm. The flow pattern of the micro channel fluid and the dynamic evolution process of the micro droplet generation in the plus wave driving were researched.

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19

Kitamura, Keiichi, Meng-Sing Liou, and Chih-Hao Chang. "Extension and Comparative Study of AUSM-Family Schemes for Compressible Multiphase Flow Simulations." Communications in Computational Physics 16, no. 3 (September 2014): 632–74. http://dx.doi.org/10.4208/cicp.020813.190214a.

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AbstractSeveral recently developed AUSM-family numerical flux functions (SLAU, SLAU2, AUSMM+-up2, and AUSMPW+) have been successfully extended to compute compressible multiphase flows, based on the stratified flow model concept, by following two previous works: one by M.-S. Liou, C.-H. Chang, L. Nguyen, and T.G. Theofanous [AIAA J. 46:2345-2356, 2008], in which AUSM+-up was used entirely, and the other by C.-H. Chang, and M.-S. Liou [J. Comput. Phys. 225:840-873, 2007], in which the exact Riemann solver was combined into AUSM+-up at the phase interface. Through an extensive survey by comparing flux functions, the following are found: (1) AUSM+-up with dissipation parameters of Kp and Ku equal to 0.5 or greater, AUSMPW+, SLAU2, AUSM+-up2, and SLAU can be used to solve benchmark problems, including a shock/water-droplet interaction; (2) SLAU shows oscillatory behaviors [though not as catastrophic as those of AUSM+ (a special case of AUSM+-up with Kp = Ku = 0)] due to insufficient dissipation arising from its ideal-gas-based dissipation term; and (3) when combined with the exact Riemann solver, AUSM+-up (Kp = Ku = 1), SLAU2, and AUSMPW+ are applicable to more challenging problems with high pressure ratios.

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20

Hosseini, Seyed Ali, Hesameddin Safari, and Dominique Thevenin. "Lattice Boltzmann Solver for Multiphase Flows: Application to High Weber and Reynolds Numbers." Entropy 23, no. 2 (January 29, 2021): 166. http://dx.doi.org/10.3390/e23020166.

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The lattice Boltzmann method, now widely used for a variety of applications, has also been extended to model multiphase flows through different formulations. While already applied to many different configurations in low Weber and Reynolds number regimes, applications to higher Weber/Reynolds numbers or larger density/viscosity ratios are still the topic of active research. In this study, through a combination of a decoupled phase-field formulation—the conservative Allen–Cahn equation—and a cumulant-based collision operator for a low-Mach pressure-based flow solver, we present an algorithm that can be used for higher Reynolds/Weber numbers. The algorithm was validated through a variety of test cases, starting with the Rayleigh–Taylor instability in both 2D and 3D, followed by the impact of a droplet on a liquid sheet. In all simulations, the solver correctly captured the flow dynamics andmatched reference results very well. As the final test case, the solver was used to model droplet splashing on a thin liquid sheet in 3D with a density ratio of 1000 and kinematic viscosity ratio of 15, matching the water/air system at We = 8000 and Re = 1000. Results showed that the solver correctly captured the fingering instabilities at the crown rim and their subsequent breakup, in agreement with experimental and numerical observations reported in the literature.

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21

Turnquist, Brian, and Mark Owkes. "A fast, decomposed pressure correction method for an intrusive stochastic multiphase flow solver." Computers & Fluids 221 (May 2021): 104930. http://dx.doi.org/10.1016/j.compfluid.2021.104930.

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22

Yang, Daegil, George J. Moridis, and Thomas A. Blasingame. "A fully coupled multiphase flow and geomechanics solver for highly heterogeneous porous media." Journal of Computational and Applied Mathematics 270 (November 2014): 417–32. http://dx.doi.org/10.1016/j.cam.2013.12.029.

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23

Brunner, Fabian, and Peter Knabner. "A global implicit solver for miscible reactive multiphase multicomponent flow in porous media." Computational Geosciences 23, no. 1 (November 20, 2018): 127–48. http://dx.doi.org/10.1007/s10596-018-9788-7.

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24

Wardle, Kent E., and Henry G. Weller. "Hybrid Multiphase CFD Solver for Coupled Dispersed/Segregated Flows in Liquid-Liquid Extraction." International Journal of Chemical Engineering 2013 (2013): 1–13. http://dx.doi.org/10.1155/2013/128936.

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The flows in stage-wise liquid-liquid extraction devices include both phase segregated and dispersed flow regimes. As a additional layer of complexity, for extraction equipment such as the annular centrifugal contactor, free-surface flows also play a critical role in both the mixing and separation regions of the device and cannot be neglected. Traditionally, computional fluid dynamics (CFD) of multiphase systems is regime dependent—different methods are used for segregated and dispersed flows. A hybrid multiphase method based on the combination of an Eulerian multifluid solution framework (per-phase momentum equations) and sharp interface capturing using Volume of Fluid (VOF) on selected phase pairs has been developed using the open-source CFD toolkit OpenFOAM. Demonstration of the solver capability is presented through various examples relevant to liquid-liquid extraction device flows including three-phase, liquid-liquid-air simulations in which a sharp interface is maintained between each liquid and air, but dispersed phase modeling is used for the liquid-liquid interactions.

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25

Colombo, Marco, Andrea De Santis, Bruce C. Hanson, and Michael Fairweather. "Prediction of Horizontal Gas–Liquid Segregated Flow Regimes with an All Flow Regime Multifluid Model." Processes 10, no. 5 (May 6, 2022): 920. http://dx.doi.org/10.3390/pr10050920.

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The generalized multifluid modelling approach (GEMMA) has been developed to handle the multiplicity of flow regimes and the coexistence of interfaces of largely different scales in multiphase flows. The solver, based on the OpenFOAM reactingEulerFoam family of solvers, adds interface resolving-like capabilities to the multifluid solver in the cells occupied by large interfaces. In this paper, GEMMA is further developed to predict stratified and slug flow regimes in horizontal ducts. The suppression of the turbulence and the wall-like behaviour of large interfaces is modelled with an additional dissipation source. This enables an accurate prediction of the velocity and of the turbulence kinetic energy in a stratified channel flow and the capturing of the formation and the travel of liquid slugs in an annulus. Large interfaces are identified and tracked, not only in the smooth and wavy stratified regimes but also in the much more perturbed interfaces of liquid slugs. The present work confirms GEMMA to be a reliable approach to provide all flow regime modelling capabilities. Further development will be focused on large interface momentum-transfer modelling, responsible for the overestimation of the interfacial shear and the limited liquid excursion during slugs, and the extension to interface break-up and the entrainment of bubbles and droplets, to handle the entire range of regimes encountered in horizontal flows.

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26

Li, Wei, Yihui Ma, Xiaopei Liu, and Mathieu Desbrun. "Efficient kinetic simulation of two-phase flows." ACM Transactions on Graphics 41, no. 4 (July 2022): 1–17. http://dx.doi.org/10.1145/3528223.3530132.

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Real-life multiphase flows exhibit a number of complex and visually appealing behaviors, involving bubbling, wetting, splashing, and glugging. However, most state-of-the-art simulation techniques in graphics can only demonstrate a limited range of multiphase flow phenomena, due to their inability to handle the real water-air density ratio and to the large amount of numerical viscosity introduced in the flow simulation and its coupling with the interface. Recently, kinetic-based methods have achieved success in simulating large density ratios and high Reynolds numbers efficiently; but their memory overhead, limited stability, and numerically-intensive treatment of coupling with immersed solids remain enduring obstacles to their adoption in movie productions. In this paper, we propose a new kinetic solver to couple the incompressible Navier-Stokes equations with a conservative phase-field equation which remedies these major practical hurdles. The resulting two-phase immiscible fluid solver is shown to be efficient due to its massively-parallel nature and GPU implementation, as well as very versatile and reliable because of its enhanced stability to large density ratios, high Reynolds numbers, and complex solid boundaries. We highlight the advantages of our solver through various challenging simulation results that capture intricate and turbulent air-water interaction, including comparisons to previous work and real footage.

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Li, Yuanhong, and Song-Charng Kong. "Mesh refinement algorithms in an unstructured solver for multiphase flow simulation using discrete particles." Journal of Computational Physics 228, no. 17 (September 2009): 6349–60. http://dx.doi.org/10.1016/j.jcp.2009.05.018.

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28

AONO, Junya, and Keiichi KITAMURA. "Development of parameter-free, two-fluid, viscous multiphase flow solver for cough-droplet simulations." Journal of Fluid Science and Technology 18, no. 1 (2023): JFST0016. http://dx.doi.org/10.1299/jfst.2023jfst0016.

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29

Svenning, Erik, Andreas Mark, Fredrik Edelvik, Erik Glatt, Stefan Rief, Andreas Wiegmann, Lars Martinsson, Ron Lai, Mats Fredlund, and Ulf Nyman. "Multiphase simulation of fiber suspension flows using immersed boundary methods." Nordic Pulp & Paper Research Journal 27, no. 2 (May 1, 2012): 184–91. http://dx.doi.org/10.3183/npprj-2012-27-02-p184-191.

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Abstract Fiber suspension simulations are challenging since they involve transient fluid flow with immersed solid objects subject to large displacements and rotations. In the present work, a beam model in corotational formulation is coupled with a fluid solver using immersed boundary methods. The model is used to simulate a fiber in a shear flow and excellent agreement is found with Jeffery's equations. The shapes of fibers deforming in a shear flow are found to be in qualitative agreement with shapes observed in experiments. The flow of a fiber suspension is studied by simulating early paper forming with one-way and semi-two-way coupling. It is found that the flow through the fiber web needs to be resolved in order to predict the retention of fibers in the fiber web.

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30

Wang, Min, Chunyong Fan, and Guisheng Hou. "Numerical research of lateral flow influence on supercavitating flow." AIP Advances 12, no. 4 (April 1, 2022): 045214. http://dx.doi.org/10.1063/5.0090282.

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In this paper, a recompiled multiphase flow solver, which introduced the lateral flow source into the code, is developed to investigate the effect of the lateral flow on the supercavitation phenomenon. The evolution of the supercavity profile and the resistance of the vehicle under different lateral flow speeds are studied. The results show that the recompiled solver can calculate the effect of the lateral flow on the supercavitation, and the influence of lateral flow on the supercavity is related to the speed of the counter flow. Under the same lateral flow velocity, the higher the convection velocity, the weaker the influence of lateral flow on the cavity profile and resistance. When the lateral flow velocity is less than 8% of the convection velocity, the effect of the lateral flow on the supercavity size and the resistance of the vehicle can be ignored. As the lateral flow strengthens, the supercavity will deform and even break and the resistance of the vehicle increases significantly. After removing the source of the lateral flow, the cavity re-grows again and forms a huge supercavity, which is much larger than the original one before introducing the velocity source. Then, the cavity gradually shrinks and reaches a new steady state.

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31

Rodríguez-Ocampo, Paola Elizabeth, Michael Ring, Jassiel Vladimir Hernández-Fontes, Juan Carlos Alcérreca-Huerta, Edgar Mendoza, and Rodolfo Silva. "CFD Simulations of Multiphase Flows: Interaction of Miscible Liquids with Different Temperatures." Water 12, no. 9 (September 16, 2020): 2581. http://dx.doi.org/10.3390/w12092581.

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The incorporation of new equations to extend the applicability of open-source computational fluid dynamics (CFD) software according to the user’s needs must be complemented with code verification and validation with a representative case. This paper presents the development and validation of an OpenFOAM®-based solver suitable for simulating multiphase fluid flow considering three fluid phases with different densities and temperatures, i.e., two miscible liquids and air. A benchmark “dam-break” experiment was performed to validate the solver. Ten thermistors measured temperature variations in different locations of the experimental model and the temperature time series were compared against those of numerical probes in analogous locations. The accuracy of the temperature field assessment considered three different turbulence models: (a) zero-equation, (b) k-omega (Reynolds averaged simulation; RAS), and (c) large eddy simulation (LES). The simulations exhibit a maximum time-average relative and absolute errors of 9.3% and 3.1 K, respectively; thus, the validation tests proved to achieve an adequate performance of the numerical model. The solver developed can be applied in the modeling of thermal discharges into water bodies.

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32

Salewski, Mirko, Dragan Stankovic, and Laszlo Fuchs. "A Comparison of Single and Multiphase Jets in a Crossflow Using Large Eddy Simulations." Journal of Engineering for Gas Turbines and Power 129, no. 1 (September 28, 2005): 61–68. http://dx.doi.org/10.1115/1.2180810.

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Large eddy simulations (LES) are performed for single and multiphase jets in crossflow (JICF). The multiphase JICF are compared to the single-phase case for the same momentum and mass flow ratios but with droplets of different sizes. Multiphase JICF have stronger counterrotating vortex pairs (CVPs) than a corresponding single-phase JICF. Moreover, their trajectories are higher and their induced wakes weaker. The smaller the Stokes number of the droplets, the more the solution approaches the solution for single-phase flow. The computed results show the formation of a CVP and horseshoe vortices, which are convected downstream. LES also reveals the intermittent formation of upright wake vortices from the horseshoe vortices on the ground toward the CVP. The dispersion of polydisperse spray droplets is computed using the stochastic parcel method. Atomization and droplet breakup are modeled by a combination of the breakup model by Reitz and the Taylor analogy breakup model (see Caraeni, D., Bergström, C., and Fuchs, L., 2000, Flow, Turbul. Combust., 65(2), pp. 223–244). Evaporation and droplet collision are also modeled. The flow solver uses two-way coupling. Averages of the velocity and gaseous fuel mass fraction are computed. The single-phase JICF is validated against experimental data obtained by PIV. Additionally, the PDFs and frequency spectra are presented.

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33

Ansari, Mohaghegh, Shahnam, and Dietiker. "Modeling Average Pressure and Volume Fraction of a Fluidized Bed Using Data-Driven Smart Proxy." Fluids 4, no. 3 (July 5, 2019): 123. http://dx.doi.org/10.3390/fluids4030123.

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Simulations can reduce the time and cost to develop and deploy advanced technologies and enable their rapid scale-up for fossil fuel-based energy systems. However, to ensure their usefulness in practice, the credibility of the simulations needs to be established with uncertainty quantification (UQ) methods. The National Energy Technology Laboratory (NETL) has been applying non-intrusive UQ methodologies to categorize and quantify uncertainties in computational fluid dynamics (CFD) simulations of gas-solid multiphase flows. To reduce the computational cost associated with gas-solid flow simulations required for UQ analysis, techniques commonly used in the area of artificial intelligence (AI) and data mining are used to construct smart proxy models, which can reduce the computational cost of conducting large numbers of multiphase CFD simulations. The feasibility of using AI and machine learning to construct a smart proxy for a gas-solid multiphase flow has been investigated by looking at the flow and particle behavior in a non-reacting rectangular fluidized bed. The NETL’s in house multiphase solver, Multiphase Flow with Interphase eXchanges (MFiX), was used to generate simulation data for the rectangular fluidized bed. The artificial neural network (ANN) was used to construct a CFD smart proxy, which is able to reproduce the CFD results with reasonable error (about 10%). Several blind cases were used to validate this technology. The results show a good agreement with CFD runs while the approach is less computationally expensive. The developed model can be used to generate the time averaged results of any given fluidized bed with the same geometry with different inlet velocity in couple of minutes.

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34

Nguyen, Van-Tu, and Warn-Gyu Park. "A Review of Preconditioning and Artificial Compressibility Dual-Time Navier–Stokes Solvers for Multiphase Flows." Fluids 8, no. 3 (March 16, 2023): 100. http://dx.doi.org/10.3390/fluids8030100.

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This review paper aims to summarize recent advancements in time-marching schemes for solving Navier–Stokes (NS) equations in multiphase flow simulations. The focus is on dual-time stepping, local preconditioning, and artificial compressibility methods. These methods have proven to be effective in achieving high time accuracy in simulations, as well as converting the incompressible NS equations into a hyperbolic form that can be solved using compact schemes, thereby accelerating the solution convergence and allowing for the simulation of compressible flows at all Mach numbers. The literature on these methods continues to grow, providing a deeper understanding of the underlying physical processes and supporting technological advancements. This paper also highlights the imposition of dual-time stepping on both incompressible and compressible NS equations. This paper provides an updated overview of advanced methods for the CFD community to continue developing methods and select the most suitable two-phase flow solver for their respective applications.

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35

Duarte, Claudio Roberto, Valéria V. Murata, and Marcos A. S. Barrozo. "Simulation of Spouted Bed Using a Eulerian Multiphase Model." Materials Science Forum 498-499 (November 2005): 270–77. http://dx.doi.org/10.4028/www.scientific.net/msf.498-499.270.

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Spouted bed systems have emerged as very efficient fluid-particle contactors and find many applications in the chemical and biochemical industry. Some important applications of spouted beds include coal combustion, biochemical reactions, drying of solids, drying of solutions and suspensions, granulation, blending, grinding, and particle coating. An extensive overview can be found in Mathur and Epstein[1]. The pattern of solid and gas flows in a spouted bed was numerically simulated using a CFD modeling technique. The Eulerian-Eulerian multifluid modeling approach was applied to predict gas-solid flow behavior. A commercially available, control-volume-based code FLUENT 6.1 was chosen to carry out the computer simulations. In order to reduce computational times and required system resources, the 2D axisymmetric segregated solver was chosen. The typical flow pattern of the spouted bed was obtained in the present calculation. The simulated velocity and voidage profiles presented a good agreement qualitative and quantitative with the experimental results obtained by He et al. [4].

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36

Li, Boxiao, and Hamdi A. Tchelepi. "Unconditionally Convergent Nonlinear Solver for Multiphase Flow in Porous Media under Viscous Force, Buoyancy, and Capillarity." Energy Procedia 59 (2014): 404–11. http://dx.doi.org/10.1016/j.egypro.2014.10.395.

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37

Gel, A., S. Pannala, M. Syamlal, T. J. O'Brien, and E. S. Gel. "Comparison of frameworks for a next-generation multiphase flow solver, MFIX: a group decision-making exercise." Concurrency and Computation: Practice and Experience 19, no. 5 (2007): 609–24. http://dx.doi.org/10.1002/cpe.1085.

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38

Salinas, P., D. Pavlidis, Z. Xie, A. Adam, C. C. Pain, and M. D. Jackson. "Improving the convergence behaviour of a fixed-point-iteration solver for multiphase flow in porous media." International Journal for Numerical Methods in Fluids 84, no. 8 (December 18, 2016): 466–76. http://dx.doi.org/10.1002/fld.4357.

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39

Guler, Hasan Gokhan, Taro Arikawa, Cuneyt Baykal, Koray Deniz GÃ¶ral, and Ahmet Cevdet Yalciner. "MOTION OF SOLID SPHERES UNDER SOLITARY WAVE ATTACK: PHYSICAL AND NUMERICAL MODELING." Coastal Engineering Proceedings, no. 36 (December 30, 2018): 81. http://dx.doi.org/10.9753/icce.v36.papers.81.

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In this study, physical and numerical test are carried out focusing on the motion of two solid spheres under solitary wave attack. The numerical model CADMAS-SURF/3D-2F-DEM coupling a multiphase flow solver solving Reynolds Averaged Navier-Stokes Equations based on a porous body model and a discrete element method solver for Newtonâ€™s equations of motion is validated against the data of physical model experiments carried out in the wave flume of METU Ocean Engineering Research Center. Comparisons of the numerical simulations and physical model experiments show that the numerical model is capable of simulating the motion of solid spheres under solitary wave attack in a reasonably well accuracy.

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40

van Odyck, Daniel E. A., Sean Lovett, Franck Monmont, and Nikolaos Nikiforakis. "An efficient shock capturing scheme for multicomponent multiphase thermal flow in porous media." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 468, no. 2147 (July 4, 2012): 3413–40. http://dx.doi.org/10.1098/rspa.2012.0152.

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This paper is concerned with multicomponent, two-phase, thermal fluid flow in porous media. The fluid model consists of component conservation equations, Darcy's law for volumetric flow rates and an enthalpy conservation equation. The model is closed with an equation of state and phase equilibrium conditions that determine the distribution of the chemical components into phases. The sequential formulation described in a previous article is used to build a second-order shock capturing scheme for the conservation equations using a primitive-variable-based linear reconstruction. The fluxes at the cell faces are calculated using an approximate Riemann solver. The method is validated and evaluated by means of one- and two-dimensional problems, including a gravity inversion test.

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41

Klemetsdal, Øystein S., Olav Møyner, and Knut-Andreas Lie. "Robust Nonlinear Newton Solver With Adaptive Interface-Localized Trust Regions." SPE Journal 24, no. 04 (June 14, 2019): 1576–94. http://dx.doi.org/10.2118/195682-pa.

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Summary The interplay of multiphase-flow effects and pressure/volume/temperature behavior encountered in reservoir simulations often provides strongly coupled nonlinear systems that are challenging to solve numerically. In a sequentially implicit method, many of the essential nonlinearities are associated with the transport equation, and convergence failure for the Newton solver is often caused by steps that pass inflection points and discontinuities in the fractional-flow functions. The industry-standard approach is to heuristically chop timesteps and/or dampen updates suggested by the Newton solver if these exceed a predefined limit. Alternatively, one can use trust regions (TRs) to determine safe updates that stay within regions that have the same curvature for numerical flux. This approach has previously been shown to give unconditional convergence for polymer- and waterflooding problems, also when property curves have kinks or near-discontinuous behavior. Although unconditionally convergent, this method tends to be overly restrictive. Herein, we show how the detection of oscillations in the Newton updates can be used to adaptively switch on and off TRs, resulting in a less-restrictive method better suited for realistic reservoir simulations. We demonstrate the performance of the method for a series of challenging test cases ranging from conceptual 2D setups to realistic (and publicly available) geomodels such as the Norne Field and the recent Olympus model from the Integrated Systems Approach for Petroleum Production (ISAPP) optimization challenge.

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42

Zwick, D., and S. Balachandar. "Dynamics of rapidly depressurized multiphase shock tubes." Journal of Fluid Mechanics 880 (October 9, 2019): 441–77. http://dx.doi.org/10.1017/jfm.2019.710.

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Rapid depressurization is a fluid phenomenon that occurs in many industrial and natural applications. Its behaviour is often complicated by the formation, propagation and interaction of waves. In this work, we perform computer simulations of the rapid depressurization of a gas–solid mixture in a shock tube. Our problem set-up mimics previously performed experiments, which have been historically used as a laboratory surrogate for volcanic eruptions. The simulations are carried out with a discontinuous Galerkin compressible fluid solver with four-way coupled Lagrangian particle tracking capabilities. The results give an unprecedented look into the complex multiphase physics at work in this problem. Different regimes have been characterized in a regime map that highlights the key observations. While the mean flow behaviour is in good agreement with experiments, the simulations show unexpected accelerations of the particle front as it expands. Additionally, a new lifting mechanism for gas bubble (void) growth inside the gas–solid mixture is detailed.

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43

Chen, Dezhu, Xin Tong, Bin Xie, Feng Xiao, and Ye Li. "An accurate and efficient multiphase solver based on THINC scheme and adaptive mesh refinement." International Journal of Multiphase Flow 162 (May 2023): 104409. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2023.104409.

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44

Zhang, Jia Zhong, Tian Qing You, Qian Kun He, Ying Jie Wei, and Cong Wang. "Numerical Analysis of Cavitation Flow during Vertical Water Exit of Underwater Vehicles." Advanced Materials Research 201-203 (February 2011): 2780–84. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.2780.

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During water-exit of underwater vehicle, the high pressure， which the local cavity collapse of underwater vehicle causes, poses a great challenge to the vehicle structure. The cavity collapse during vertical water exit of an underwater vehicle is simulated by a viscous flow solver with homogeneous multiphase flow model. The shrinkage and collapse of cavity zone and violent changes of the pressure field have been captured during the simulation. The changes of cavity shape and pressure field at different water exit velocity have been analyzed. It has been concluded that higher velocity may cause the delay of cavity total collapse and the max pressure point to transfer backwards.

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45

Yang, Jianhui, Yi Xu, and Liang Yang. "Taichi-LBM3D: A Single-Phase and Multiphase Lattice Boltzmann Solver on Cross-Platform Multicore CPU/GPUs." Fluids 7, no. 8 (August 8, 2022): 270. http://dx.doi.org/10.3390/fluids7080270.

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The success of the lattice Boltzmann method requires efficient parallel programming and computing power. Here, we present a new lattice Boltzmann solver implemented in Taichi programming language, named Taichi-LBM3D. It can be employed on cross-platform shared-memory many-core CPUs or massively parallel GPUs (OpenGL and CUDA). Taichi-LBM3D includes the single- and two-phase porous medium flow simulation with a D3Q19 lattice model, Multi-Relaxation-Time (MRT) collision scheme and sparse data storage. It is open source, intuitive to understand, and easily extensible for scientists and researchers.

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46

Friedrich, Jonas, and Michael Schäfer. "Towards an Acoustic Simulation of a Water Drop Impacting in a Water Pool." Flow, Turbulence and Combustion 105, no. 4 (April 10, 2020): 1231–47. http://dx.doi.org/10.1007/s10494-020-00130-4.

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AbstractThe sound which is produced when a water drop impacts into a water pool is a prominent example for acoustics produced by multiphase flow. In this work the feasibility of numerical methods for simulating this challenging test case is evaluated. First the multiphase flow needs to produce the correct physical mechanisms, e.g. the bubble entrapment. For this an in-house block-structured finite-volume solver with the volume-of-fluid method is used. For the curvature computation a standard finite difference method within the continuum surface force model is employed, including some necessary improvements. A high resolution in space and time is essential and therefore the method is parallelized by domain decomposition. The acoustic part is simulated with the linearized Euler equations which are valid in each phase but need to be adapted in the interface region. The results are compared with numerical and experimental data. It is shown, that the methods are suitable for simple test cases. A coupled drop impact test case corresponds with equivalent experiments until the drop detachment. The acoustic pressure shows a significant rise in the vicinity of the bubble detachment within both phases. However, an oscillation of the cavity bottom can not be observed in the multiphase neither in the acoustic outputs of the airborne signal.

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47

정세민, Jong-Chun Park, and Duan Ming-Hao. "Development of Numerical Solver for the Simulation on Multiphase Flow in a Pipeline of Mud Handling System." Journal of Advanced Engineering and Technology 9, no. 3 (September 2016): 163–70. http://dx.doi.org/10.35272/jaet.2016.9.3.163.

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48

USHIJIMA, Satoru, Akira FUKUTANI, Norimasa YOSHIKAWA, and Iehisa NEZU. "NUMERICAL PREDICTION FOR COLLAPSE OF PERMEABLE DAM DUE TO OVERFLOWS WITH 3D MULTIPHASE-FLOW SOLVER (3D MICS)." PROCEEDINGS OF HYDRAULIC ENGINEERING 50 (2006): 841–46. http://dx.doi.org/10.2208/prohe.50.841.

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49

Ma, Z. H., D. M. Causon, L. Qian, C. G. Mingham, H. B. Gu, and P. Martínez Ferrer. "A compressible multiphase flow model for violent aerated wave impact problems." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 470, no. 2172 (December 8, 2014): 20140542. http://dx.doi.org/10.1098/rspa.2014.0542.

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This paper focuses on the numerical modelling of wave impact events under air entrapment and aeration effects. The underlying flow model treats the dispersed water wave as a compressible mixture of air and water with homogeneous material properties. The corresponding mathematical equations are based on a multiphase flow model which builds on the conservation laws of mass, momentum and energy as well as the gas-phase volume fraction advection equation. A high-order finite volume scheme based on monotone upstream-centred schemes for conservation law reconstruction is used to discretize the integral form of the governing equations. The numerical flux across a mesh cell face is estimated by means of the HLLC approximate Riemann solver. A third-order total variation diminishing Runge–Kutta scheme is adopted to obtain a time-accurate solution. The present model provides an effective way to deal with the compressibility of air and water–air mixtures. Several test cases have been calculated using the present approach, including a gravity-induced liquid piston, free drop of a water column in a closed tank, water–air shock tubes, slamming of a flat plate into still pure and aerated water and a plunging wave impact at a vertical wall. The obtained results agree well with experiments, exact solutions and other numerical computations. This demonstrates the potential of the current method to tackle more general wave–air–structure interaction problems.

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50

Oda, T., T. Yano, and Y. Niboshi. "Development and exploitation of a multipurpose CFD tool for optimisation of microbial reaction and sludge flow." Water Science and Technology 53, no. 3 (February 1, 2006): 101–10. http://dx.doi.org/10.2166/wst.2006.080.

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A numerical analysis technique for optimisation of microbial reaction and sludge flow has been developed in this study. The technique is based on the 3D multiphase Navier–Stokes solver with turbulence models. In order to make numerical analyses of the total processes in wastewater treatment plants possible, four numerical models, the microbial reaction model, a sludge settling model, oxygen mass transfer model from coarse bubbles, and a model from fine bubbles, are added to the solver. All parameters included in those models are calibrated in accordance with experimental results, and good agreements between calculated results and experimental results are found. Finally, this study shows that the numerical technique can be used to optimise wastewater treatment plants with an example of the operational optimisation of an intermittent agitation in anoxic reactors by coarse bubbles. With a proper appreciation of its limit and advantages, the exploitation of the CFD efficiently leads us to the right direction even though it is not quantitatively perfect.

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