Gotowa bibliografia na temat „Multiphase Solver”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Zobacz listy aktualnych artykułów, książek, rozpraw, streszczeń i innych źródeł naukowych na temat „Multiphase Solver”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Artykuły w czasopismach na temat "Multiphase Solver"
1
Wang, Yan, Chang Shu, Li-Ming Yang i Hai-Zhuan Yuan. "Development of axisymmetric lattice Boltzmann flux solver for complex multiphase flows". Modern Physics Letters B 32, nr 12n13 (10.05.2018): 1840005. http://dx.doi.org/10.1142/s0217984918400055.
Pełny tekst źródłaStreszczenie:
This paper presents an axisymmetric lattice Boltzmann flux solver (LBFS) for simulating axisymmetric multiphase flows. In the solver, the two-dimensional (2D) multiphase LBFS is applied to reconstruct macroscopic fluxes excluding axisymmetric effects. Source terms accounting for axisymmetric effects are introduced directly into the governing equations. As compared to conventional axisymmetric multiphase lattice Boltzmann (LB) method, the present solver has the kinetic feature for flux evaluation and avoids complex derivations of external forcing terms. In addition, the present solver also saves considerable computational efforts in comparison with three-dimensional (3D) computations. The capability of the proposed solver in simulating complex multiphase flows is demonstrated by studying single bubble rising in a circular tube. The obtained results compare well with the published data.
2
Chen, Guo-Qing, Hongyuan Li, Pengyu Lv i Huiling Duan. "An improved multiphase lattice Boltzmann flux solver with phase interface compression for incompressible multiphase flows". Physics of Fluids 35, nr 1 (styczeń 2023): 013310. http://dx.doi.org/10.1063/5.0131506.
Pełny tekst źródłaStreszczenie:
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.
3
Lin, Zhipeng, Wenjing Yang, Houcun Zhou, Xinhai Xu, Liaoyuan Sun, Yongjun Zhang i Yuhua Tang. "Communication Optimization for Multiphase Flow Solver in the Library of OpenFOAM". Water 10, nr 10 (16.10.2018): 1461. http://dx.doi.org/10.3390/w10101461.
Pełny tekst źródłaStreszczenie:
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.
4
Nguyen, Viet-Bac, Quoc-Vu Do i Van-Sang Pham. "An OpenFOAM solver for multiphase and turbulent flow". Physics of Fluids 32, nr 4 (1.04.2020): 043303. http://dx.doi.org/10.1063/1.5145051.
Pełny tekst źródła
5
Wang, Y., C. Shu, H. B. Huang i C. J. Teo. "Multiphase lattice Boltzmann flux solver for incompressible multiphase flows with large density ratio". Journal of Computational Physics 280 (styczeń 2015): 404–23. http://dx.doi.org/10.1016/j.jcp.2014.09.035.
Pełny tekst źródła
6
Jafarian, Ali, i Ahmadreza Pishevar. "An exact multiphase Riemann solver for compressible cavitating flows". International Journal of Multiphase Flow 88 (styczeń 2017): 152–66. http://dx.doi.org/10.1016/j.ijmultiphaseflow.2016.08.001.
Pełny tekst źródła
7
Ivanov, E. A., A. S. Klyuyev, A. A. Zharkovskii i 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.
Pełny tekst źródłaStreszczenie:
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.
8
Abas, Aizat, N. Hafizah Mokhtar, M. H. H. Ishak, M. Z. Abdullah i 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.
Pełny tekst źródłaStreszczenie:
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.
9
Jiang, LiJuan, HongGuang Sun i Yan Wang. "Modeling immiscible fluid flow in fractal pore medium by multiphase lattice Boltzmann flux solver". Physics of Fluids 35, nr 2 (luty 2023): 023334. http://dx.doi.org/10.1063/5.0137360.
Pełny tekst źródłaStreszczenie:
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.
10
Guo, Yisen, i Yongsheng Lian. "Calculation of Water Collection Efficiency Using a Multiphase Flow Solver". Journal of Aircraft 56, nr 2 (marzec 2019): 685–94. http://dx.doi.org/10.2514/1.c034793.
Pełny tekst źródłaRozprawy doktorskie na temat "Multiphase Solver"
1
Dhruv, Akash. "A Multiphase Solver for High-Fidelity Phase-Change Simulations over Complex Geometries". Thesis, The George Washington University, 2021. http://pqdtopen.proquest.com/#viewpdf?dispub=28256871.
Pełny tekst źródłaStreszczenie:
Complex interactions between solid, liquid and gas occur in many practical engineering applications, and are often difficult to quantify experimentally. A few examples include boiling over solid heaters, solidification melt-dynamics in metal casting, and convective cooling of electronic components. With the availability of scalable computational tools, high-fidelity simulations can provide new insight into these phenomena and answer open questions. In the present work, a multiphase solver is presented which can simulate problems involving phase transition over complex geometries. The dynamics of liquid-gas interface are modeled using a level-set technique, which utilizes Ghost Fluid Method (GFM) to account for sharp jump in pressure, velocity, and temperature across the multiphase boundary. The fluid-solid interactions are modeled using an Immersed Boundary Method (IBM) which uses a Moving Least Squared (MLS) reconstruction to calculate fluid-flow around the solid, along with an additional GFM forcing to model its effect on pressure, temperature and Conjugate Heat Transfer (CHT). The resulting three dimensional solver is fully explicit in time and uses a fractional step method for Navier-Stokes, energy, and mass transfer equations. Validation and verification cases are presented to demonstrate the accuracy of the solver in comparison to experimental and analytical problems, and results of high fidelity pool boiling simulations in varying gravity environments are discussed in detail.
2
Lezeau, Patrick A. "An adaptive quasi-Newton coupled multigrid solver for the simulation of steady multiphase flows". Thesis, Cranfield University, 1997. http://hdl.handle.net/1826/4025.
Pełny tekst źródłaStreszczenie:
This thesis is concerned with the application of adaptive local quasi-Newton coupled
multigrid (ALQNMG) solvers to the numerical simulation of viscous incompressible
fluids, using the multi-fluid model.
The ALQNMG methodologyh as proven highly successful for single phase flows [1],
leading to solution algorithms which are: (i) robust, (ii) efficient and (iii) accurate.
Its extension to multiphase flows is very challenging because the governing equations
are mathematically complex and their solutions are subject to constraints.
The solver presented here has therefore required a considerable number of specific
algorithmic developments.
The outline of the thesis is as follows: firstly, the modelling and simulation of multiphase
flows are reviewed, together with the different numerical techniques implemented
in the solver. Finite volume discrete multiphase equations are then derived
on structured, staggered grids. Next, having specified the solution algorithm, we
consider the accuracy of the solver. Results from several test cases of varying complexity
are compared with those of a widely used commercial CFD package and good
agreementis obtained.
The question of performance is then addressed in detail, both in terms of robustness
and speed of convergence. Good accelerations are obtained using the multigrid
method but the convergence rates are often not grid-independent. The most likely
explanation is that the discrete operators are highly non-linear and therefore have
different characteristics on different grids. Furthermore, the solution algorithm is
shown to not handle certain multiphase diffusive terms very well. Convergence rates
are much faster than those achieved by single grid solvers and commercial codes
typically by one order of magnitude and often more, although the solver is not fully
optimal.
Finally, adaption is considered. Grids are generated automatically which facilitates
the use of the code and allows error control. It is confirmed that multigrid methods
offer a good framework for the implementation of adaption. Considerable gains in
speed and memory usage, by one further order of magnitude, are achieved.
3
Heyns, Johan Adam. "Formulation of a weakly compressible two-fluid flow solver and the development of a compressive surface capturing scheme using the volume-of-fluid approach". Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71934.
Pełny tekst źródłaStreszczenie:
Thesis (PhD)--Stellenbosch University, 2012ENGLISH ABSTRACT: This study presents the development and extension of free-surface modelling techniques for the purpose of modelling two-fluid systems accurately and efficiently. The volume-of-fluid (VOF) method is extended in two ways: Firstly, it is extended to account for variations in the gas density through a weakly compressible formulation. Secondly, a compressive free-surface interface capturing formulation that preserves the integrity of the interface shape is detailed. These formulations were implemented and evaluated using the Elemental software. Under certain flow conditions liquid-gas systems may be subjected to large variations in pressure, making it necessary to account for changes in gas density. Modelling this effectively has received relatively little attention in the context of free-surface modelling and remains a challenge to date. To account for the variations in gas density a weakly compressible free-surface modelling formulation is developed for low Mach number flows. The latter is formally substantiated via a non-dimensional analysis. It is proposed that the new formulation advances on existing free-surface modelling formulations by effecting an accurate representation of the dominant physics in an efficient and effective manner. The proposed weakly compressible formulation is discretised using a vertexcentred edge-base finite volume approach, which provides a computationally efficient method of data structuring and memory usage. Furthermore, this implementation is applicable to unstructured spatial discretisation and parallel computing. In this light, the discretisation is formulated to ensure a stable, oscillatory free solution. Furthermore, the governing equations are solved in a fully coupled manner using a combination of dual time-stepping and a Generalised Minimum Residual solver with Lower-Upper Symmetric Gauss-Seidel preconditioning, ensuring a fast and efficient solution. The newly developed VOF interface capturing formulation is proposed to advance on the accuracy and efficiency with which the evolution of the free-surface interface is modelled. This is achieved through a novel combination of a blended higher-resolution scheme, used to interpolate the volume fraction face value, and the addition of an artificial compressive term to the VOF equation. Furthermore, the computational efficiency of the higher-resolution scheme is improved through the reformulation of the normalised variable approach and the implementation of a new higher-resolution blending function. For the purpose of evaluating the newly developed methods, several test cases are considered. It is demonstrated that the new surface capturing formulation offers a significant improvement over existing schemes, particularly at large CFL numbers. It is shown that the proposed method achieves a sharper, better defined interface for a wide range of flow conditions. With the validation of the weakly compressible formulation, it is found that the numerical results correlate well with analytical solutions. Furthermore, the importance of accounting for gas compressibility is demonstrated via an application study. The weakly compressible formulation is also found to result in negligible additional computational cost while resulting in improved convergence rates.
AFRIKAANSE OPSOMMING: Hierdie studie behels die ontwikkeling van numeriese tegnieke met die doel om twee-vloeistof vloei akkuraat en numeries effektief te modelleer. Die volume-vanvloeistof metode word op twee maniere uitgebrei: Eerstens word variasie van die gasdigtheid in ag geneem deur gebruik te maak van ’n swak samedrukbare model. Tweedens saam is ’n hoë-resolusie metode geformuleer vir die voorstelling van die vloeistof-oppervlak. Hierdie uitbreidings is met die behulp van die Elemental programmatuur geïmplementeer en met behulp van die programmatuur geëvalueer. Onder sekere toestande ervaar vloeistof-gas mengsels groot veranderinge in druk. Dit vereis dat die variasie in gasdigtheid in berekening gebring moet word. Die modellering hiervan het egter tot dusver relatief min aandag ontvang. Om hierdie rede word ’n swak samedrukbare model vir lae Mach-getalle voorgestel om die variasie in gasdigtheid in te reken. Die formulering volg uit ’n nie-dimensionele analise. Daar word geargumenteer dat die nuwe formulering die fisika meer akkuraat verteenwoordig. ’n Gesentraliseerde hoekpunt, rant gebaseerde eindige volume metode word gevolg om die differensiaalvergelykings numeries te diskretiseer. Dit bied ’n doeltreffende manier vir datastrukturering en geheuebenutting. Hierdie benadering is verder geskik vir toepassing op ongestruktureerde roosters en parallelverwerking. Die diskretisering is geformuleer om ’n stabiele oplossing sonder numeriese ossillasies te verseker. Die vloeivergelykings word op ’n gekoppelde wyse opgelos deur gebruik te maak van ’n kombinasie van ’n pseudo tyd-stap metode en ’n Veralgemene Minimum Residu berekeningsmetode met Onder-Bo Simmetriese Gauss- Seidel voorafbewerking. Die nuut ontwikkelde skema vir die modellering van die vloeistof-oppervlak is veronderstel om ’n meer akkurate voorstelling te bied en meer doeltreffend te wees vir numeriese berekeninge. Dit word bereik deur die nuwe kombinasie van ’n hoë-resolusie skema, wat gebruik word om die volumefraksie te interpoleer, met die samevoeging van ’n kunsmatige term in die volume-van-vloeistof vergelyking om die resolusie te verfyn. Verder is die doeltreffendheid van die skema verbeter deur die genormaliseerde veranderlikes benadering te herformuleer en deur die ontwikkeling van ’n nuwe hoë-resolusie vermengingsfunksie. Verskeie toetsgevalle is uitgevoer met die doel om die nuwe modelle te evalueer. Daar word aangetoon dat die nuwe skema vir die modellering van die vloeistofoppervlak ’n meetbare verbetering bied, veral by hoër Courant-Friedrichs-Lewy getalle. Die nuwe formulering bied dus hoër akkuraatheid vir ’n wye verskeidenheid van toestande. Vir die swak samedrukbare formulering is daar ’n goeie korrelasie tussen die numeriese resultate en die analitiese oplossing. In ’n toegepassingsgeval word die noodsaaklikheid om die samedrukbaarheid van die gas in ag te neem gedemonstreer. Die addisionele berekening-kostes van die nuwe formulering is weglaatbaar en in sommige gevalle verhoog die tempo waarteen die oplossing konvergeer
4
Furfaro, Damien. "Simulation numérique d'écoulements multiphasiques, problèmes à interfaces et changement de phase". Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4751/document.
Pełny tekst źródłaStreszczenie:
Ce travail porte sur la simulation numérique des écoulements multiphasiques compressibles en déséquilibre de vitesses. Un solveur de Riemann diphasique de type HLLC, à la fois robuste, simple et précis est développé et validé à partir de solutions exactes et de données expérimentales. Cette méthode numérique est étendue au cas 3D non-structuré. Par ailleurs, la construction d’une technique numérique pour la répartition de l’énergie d’une onde de choc dans les différentes phases constituant le milieu est établie et permet le respect des conditions de choc multiphasiques. L’extension multiphasique du solveur de Riemann de type HLLC est réalisée, permettant ainsi la simulation d’une plus large gamme d’applications. Enfin, un modèle de transfert de chaleur et de masse dans un brouillard de gouttes ou nuage de bulles, en présence d’effets couplés de diffusion thermique et massiques, est proposé et dévoile des résultats intéressantsThis work deals with the numerical simulation of compressible multiphase flows in velocity disequilibrium. A HLLC-type two-phase Riemann solver is developed and validated against exact solutions and experimental data. This solver is robust, simple, accurate and entropy preserving. The numerical method is then implemented in 3D unstructured meshes. Furthermore, a numerical technique consisting in enforcing the correct energy partition at a discrete level in agreement with the multiphase shock relations is built. The multiphase extension of the HLLC-type Riemann solver is realized and allows the simulation of a wide range of applications. Finally, a droplet heat and mass transfer model with large range of validity is derived. It is valid in any situation: evaporation, flashing and condensation. It accounts for coupled heat and mass diffusion in the gas phase, thermodynamics of the multi-component gas mixture and heat diffusion inside the liquid droplet, enabling in this way consideration of both droplets heating and cooling phenomena
5
Gosavi, Shekhar Vishwanath. "An integrated finite element and finite volume code to solve thermo-hydro-mechanical problems in porous media". Diss., Manhattan, Kan. : Kansas State University, 2006. http://hdl.handle.net/2097/157.
Pełny tekst źródła
6
Grenier, Nicolas. "Modélisation numérique par la méthode SPH de la séparation eau-huile dans les séparateurs gravitaires". Phd thesis, Nantes, 2009. http://tel.archives-ouvertes.fr/tel-00664668.
Pełny tekst źródłaStreszczenie:
Dans l'industrie d'extraction pétrolière, l'efficacité des séparateurs eau-huile pour la production offshore est cruciale. L'objet de ce travail est de mettre en place les outils numériques nécessaires à la modélisation du fonctionnement de ces systèmes. Les phénomènes physiques entrant en jeu sont principalement : la présence d'interfaces entre des fluides non miscibles, la viscosité de ces fluides, et les effets de tension superficielle. Les modèles physiques et numériques correspondants ont été implémentés dans le cadre de la méthode numérique SPH (Smoothed Particle Hydrodynamics) développée au L.M.F.. Cette méthode numérique appartient à la classe des méthodes particulaires (sans maillage), suivant une approche d'écoulement compressible et avec une résolution explicite. Pour modéliser au mieux les écoulements bifluides, la formulation historique de la SPH a été enrichie par deux approches différentes, développées simultanément. Chacune d'entre elles a été validée séparément. La physique supplémentaire a été rajoutée par des modèles communs qui ont été validés sur différents cas tests tels que l'écoulement de Poiseuille, les instabilités de Rayleigh-Taylor, des cas d'envahissement ou l'évolution de bulles dans un liquide. Ce dernier cas a permis la comparaison aux outils de conception utilisés dans le procédé d'ingénierie de SAIPEM S.A., par l'intermédiaire d'une validation sur la loi de Stokes. Finalement, les capacités de la méthode sont illustrées sur la séparation eau-huile dans un séparateur de géométrie simplifiée.
7
Ananthan, M. "Multiscale Simulations in Multiphase Flows". Thesis, 2017. http://etd.iisc.ac.in/handle/2005/4287.
Pełny tekst źródłaStreszczenie:
Matter at small scales is not a continuum. Whenever we are dealing with phenomena which have disparate time and length scales, we have to rely on multiscale modelling approach in order to capture the complete physics. A common scenario in multiphase flow simulations is the formation of thin fluid films in between colliding fluid masses or between a fluid mass and a surface. These films are very thin (O(100nm)) and during the Direct Numerical Simulations (DNS) of multiphase flows it is impractical to resolve their thickness fully due to highly disparate time and length scales. Our approach here is to couple a complex thin film model derived analytically to a finite volume solver (and can also be used for standard interface capturing technique like Volume of Fluid method) so that we can capture the formation and evolution of thin films which come into existence in the sub-grid thickness. In the present work, we have formulated a thin film model where viscous forces, surface tension forces and long-range intermolecular forces play the dominant role. Since the modelled equation is highly stiff in nature and these films in realistic scenarios are spread over a large area, we have developed a parallel solver for solving the resulting set of equations. We propose an algorithm to couple the thin film model to a finite volume solver. First, we study a simple square domain containing a single phase, undergoing a shear flow with periodic flow in the horizontal direction, that is simulated using finite volume method coupled to a complex thin film model. Next, we develop a robust multiphase flow solver using Coupled Level-set Volume of Fluid method as the interface capturing technique and propose an algorithm to couple the rigorously validated multiphase solver to the thin film model.
8
Thompson, Travis Brandon. "Results towards a Scalable Multiphase Navier-Stokes Solver for High Reynolds Number Flows". Thesis, 2013. http://hdl.handle.net/1969.1/151245.
Pełny tekst źródłaStreszczenie:
The incompressible Navier-Stokes equations have proven formidable for nearly a century. The present difficulties are mathematical and computational in nature; the computational requirements, in particular, are exponentially exacerbated in the presence of high Reynolds number. The issues are further compounded with the introduction of markers or an immiscible fluid intended to be tracked in an ambient high Reynolds number flow; despite the overwhelming pragmatism of problems in this regime, and increasing computational efficacy, even modest problems remain outside the realm of direct approaches.
Herein three approaches are presented which embody direct application to problems of this nature. An LES model based on an entropy-viscosity serves to abet the computational resolution requirements imposed by high Reynolds numbers and a one-stage compressive flux, also utilizing an entropy-viscosity, aids in accurate, efficient, conservative transport, free of low order dispersive error, of an immiscible fluid or tracer. Finally, an integral commutator and the theory of anti-dispersive spaces is introduced as a novel theoretical tool for consistency error analysis; in addition the material engenders the construction of error-correction techniques for mass lumping schemes.
9
DI, GIORGIO SIMONE. "Development of a gas–liquid multiphase solver for direct numerical simulation of atomization phenomena". Doctoral thesis, 2021. http://hdl.handle.net/11573/1549308.
Pełny tekst źródłaStreszczenie:
Gas-liquid multiphase flows play an essential role in nature and industry. Understanding the complex dynamics of multiphase flows is fundamental in many technological applications, including metal forming and energy production industries. In aerospace applications, multiphase flows have considerable importance in the atomization and mixing of fuels, as well as in sloshing in fuel tanks. In nature, one of the most complicated and important phenomena is the breaking of waves, in which complex atomization processes occur, leading to the formation of bubbles, droplets, spray, and aerosol. In this thesis work, we develop an efficient solver for direct numerical
simulation of the incompressible Navier-Stokes equations to study multiphase flow phenomena as bubble dynamics and formation, and atomization phenomena, in both natural and artificial flows. In the first part of the thesis, we present the basic equations that govern multiphase flow dynamics within the one-fluid formulation approach. The solver relies on the Volume-of-Fluid (VOF) method to account for different phases, and the interface tracking is carried out using novel schemes based on a tailored TVD limiter. A staggered Cartesian mesh is used, and space derivatives approximated with second-order finite-difference formulas to guarantee discrete energy preservation. Moreover, for time integration, Adams-Bashfort extrapolation is used for the convective terms and interface tracking, whereas implicit Crank-Nicolson time integration is used for the viscous terms. Surface tension is accounted for through the continuous surface force (CFS) approach, and the local interface curvature is approximated through a hierarchical approach, whereby the height function method is locally replaced with least-square derivative estimation at critical points. Several validation test cases are then presented. First, capillary wave motion and bubble in a shearing field are studied to validate surface tension discretization. Second, the dynamics of a rising bubble in a liquid tank are presented, and the results are compared with other authors. Finally, we analyze the physics of gas-liquid multiphase flows occurring in natural flows. We consider natural wave breaking
phenomena by focusing on the associated energy dissipation and the formation of spray, droplets, and bubbles.
10
Kadioglu, Samet Y. Sussman Mark M. "All speed multi-phase flow solvers". Diss., 2005. http://etd.lib.fsu.edu/theses/available/etd-07012005-152645.
Pełny tekst źródłaStreszczenie:
Thesis (Ph. D.)--Florida State University, 2005.Advisor: Mark Sussman, Florida State University, College of Arts and Sciences, Dept. of Mathematics. Title and description from dissertation home page (viewed Oct. 12, 2005). Document formatted into pages; contains xi, 104 pages. Includes bibliographical references.
Książki na temat "Multiphase Solver"
1
Al-Safran, Eissa M., i James P. Brill. Applied Multiphase Flow in Pipes and Flow Assurance: Oil and Gas Production. Society of Petroleum Engineers, 2017. http://dx.doi.org/10.2118/9781613994924.
Pełny tekst źródłaStreszczenie:
Applied Multiphase Flow in Pipes and Flow Assurance - Oil and Gas Production delivers the most recent advancements in multiphase flow technology while remaining easy to read and appropriate for undergraduate and graduate petroleum engineering students. Responding to the need for a more up-to-the-minute resource, this highly anticipated new book represents applications on the fundamentals with new material on heat transfer in production systems, flow assurance, transient multiphase flow in pipes and the TUFFP unified model. The complex computation procedure of mechanistic models is simplified through solution flowcharts and several example problems. Containing over 50 solved example problems and 140 homework problems, this new book will equip engineers with the skills necessary to use the latest steady-state simulators available.
2
Whitson, Curtis H., i Michael R. Brulé. Phase Behavior. Society of Petroleum Engineers, 2000. http://dx.doi.org/10.2118/9781555630874.
Pełny tekst źródłaStreszczenie:
This important addition to any petroleum engineer’s library covers all aspects of gas/oil phase behavior and includes a brief discussion of multiphase and vapor/solid phase behavior. Phase Behavior provides the reader with the tools needed to solve problems requiring a description of phase behavior and specific pressure/volume/temperature (PVT) properties. Also included are four appendices, including an overview of understanding laboratory oil PVT reports by M.B. Standing.
Części książek na temat "Multiphase Solver"
1
Manzanero, Juan, Carlos Redondo, Gonzalo Rubio, Esteban Ferrer, Eusebio Valero, Susana Gómez-Álvarez i Ángel Rivero-Jiménez. "A High-Order Discontinuous Galerkin Solver for Multiphase Flows". W Lecture Notes in Computational Science and Engineering, 313–23. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-39647-3_24.
Pełny tekst źródła
2
Bian, Qingyong, Chang Shu, Ning Zhao, Chengxiang Zhu i Chunling Zhu. "Numerical Investigation of Droplet Impact on the Surface by Multiphase Lattice Boltzmann Flux Solver". W Lecture Notes in Electrical Engineering, 671–84. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-2689-1_52.
Pełny tekst źródła
3
Knodel, Markus M., Serge Kräutle i Peter Knabner. "Global Implicit Solver for Multiphase Multicomponent Flow in Porous Media with Multiple Gas Phases and General Reactions". W Finite Volumes for Complex Applications IX - Methods, Theoretical Aspects, Examples, 595–603. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-43651-3_56.
Pełny tekst źródła
4
Ullah, Hafiz Khadim, Sikiru Oluwarotimi Ismail i Kumar Shantanu Prasad. "Assessment of Effectiveness of Hollow Fins for Performance Enhancement of Solar Still Device Using Simulation Approach". W Springer Proceedings in Energy, 145–55. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-30960-1_15.
Pełny tekst źródłaStreszczenie:
AbstractUnavailability of relatively clean water for several industrial, domestic and agricultural purposes is a serious concern to many regions of the world today. This challenge is growing worse with the increasing world global warming and human population. Therefore, there is need to research into an innovative, sustainable and/or improved technology for an efficient and effective solution, such as desalination. Desalination of freely available sea water is considered a promising source of fresh water. Solar radiation is abundant and can be used to desalinate water, using a solar still device. Also, it is important to increase the productivity of the solar still device through hollow fin modification. Therefore, the effectiveness of this improvement was investigated in this study, using an analysis system (ANSYS) Fluent computational fluid dynamic (CFD) simulation. Appropriate models were used to describe the physical processes, including condensation, evaporation, multiphase flow, surface tension and solar radiation. A close agreement between the simulation values of solar energy and the water temperature in the basin was observed when compared with the experimental data from the literature. Velocity of 0.259 m/s, pressure of 55.8 Pa, temperature of 57.85 ºC and mass transfer rate of 1.41 kg/m3/s were obtained in the mid-plane of the improved double slope single basin (DSSB). The degree of improvement was 5–7% when compared with the existing models. Importantly, this process is economically efficient and can support the concepts of sustainability and healthy living, especially in rural areas.
5
"Multiphase Lattice Boltzmann Flux Solver for Two-Phase Flows". W Lattice Boltzmann and Gas Kinetic Flux Solvers, 116–52. WORLD SCIENTIFIC, 2020. http://dx.doi.org/10.1142/9789811224690_0004.
Pełny tekst źródła
6
Jordan, Robert B. "Rate Law and Mechanism". W Reaction Mechanisms of Inorganic and Organometallic Systems. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195301007.003.0004.
Pełny tekst źródłaStreszczenie:
Once the experimental rate law has been established, the next step is to formulate a mechanism that is consistent with the rate law. The rate law will not uniquely define the mechanism but will limit the possibilities. The proposed mechanism will lead to predictions of trends in reactivity and other types of experiments that can be done to test the proposal. These aspects will be described in later chapters for specific types of reactions. Except for the simplest cases, the development of the rate law from the mechanism can be a messy exercise. The following sections describe some of the assumptions and tricks that can be used. Further discussions can be found in standard textbooks on kinetics. The problem is to determine the most reasonable mechanism(s) which will predict a rate law that is consistent with the observations. Very often this is done by analogy to previous studies on related systems, but there are some general guidelines that can be useful for writing a mechanism that will produce the desired form of the rate law. The mechanism is composed of elementary reactions whose rate laws are implied from the stoichiometry of each reaction. The elementary mechanistic steps are usually unimolecular or bimolecular reactions; termolecular reactions are very rare because of the improbability of bringing three species together. The form of the experimental rate law provides some guidelines for the construction of a mechanism. The following generalizations assume that the reaction is monophasic, but they may apply to individual steps in a multiphasic reaction. It also should be remembered that the experimental rate law may be incomplete because of experimental constraints. Then, the predicted rate law may contain terms not observed experimentally, but it should be possible to show that the extra terms are minor contributors under the conditions of the experiment. For the simplest cases, in which rate = kexp[A][B] or rate = kexp[A], the kinetics only requires a one step mechanism involving the species in the rate law. In the second case, the solvent also may be involved because its concentration will be constant and may be included in kexp .
Streszczenia konferencji na temat "Multiphase Solver"
1
Afaq, Muhammad Aaqib, Stefan Turek, Abderrahim Ouazzi i Arooj Fatima. "Monolithic Newton-Multigrid Solver for Multiphase Flow Problems with Surface Tension". W VI ECCOMAS Young Investigators Conference. València: Editorial Universitat Politècnica de València, 2021. http://dx.doi.org/10.4995/yic2021.2021.12390.
Pełny tekst źródłaStreszczenie:
We have developed a monolithic Newton-multigrid solver for multiphase flow problems which solves velocity, pressure and interface position simultaneously. The main idea of our work is based on the formulations discussed in [1], where it points out the feasibility of a fully implicit monolithic solver for multiphase flow problems via two formulations, a curvature-free level set approach and a curvature-free cutoff material function approach. Both formulations are fully implicit and have the advantages of requiring less regularity, since neither normals nor curvature are explicitly calculated, and no capillary time restriction. Furthermore, standard Navier-Stokes solvers might be used, which do not have to take into account inhomogeneous force terms. The reinitialization issue is integrated with a nonlinear terms within the formulations.The nonlinearity is treated with a Newton-type solver with divided difference evaluation of the Jacobian matrices. The resulting linearized system inside of the outer Newton solver is a typical saddle point problem which is solved using the geometrical multigrid with Vanka-like smoother using higher order stable FEM pair $Q_2/P^{\text{disc}}_1$ for velocity and pressure and $Q_2$ for all other variables. The method is implemented into an existing software packages for the numerical simulation of multiphase flows (FeatFlow). The robustness and accuracy of this solver is tested for two different test cases, i.e. static bubble and oscillating bubble, respectively [2].REFERENCES[1] Ouazzi, A., Turek, S. and Damanik, H. A curvature-free multiphase flow solver via surface stress-based formulation. Int. J. Num. Meth. Fluids., Vol. 88, pp. 18–31, (2018).[2] Afaq, M. A., Turek, S., Ouazzi, A. and Fatima, A. Monolithic Newton-Multigrid Solver for Multiphase Flow Problems with Surface Tension. Ergebnisberichte des Instituts fuer Angewandte Mathematik Nummer 636, Fakultaet fuer Mathematik, TU Dortmund University, 636, 2021.
2
Peña-Monferrer, C., J. L. Muñoz-Cobo, G. Monrós-Andreu i S. Chiva. "Development of a multiscale solver with sphere partitioning tracking". W MULTIPHASE FLOW 2015. Southampton, UK: WIT Press, 2015. http://dx.doi.org/10.2495/mpf150221.
Pełny tekst źródła
3
Kotteda, V. M. Krushnarao, Ashesh Chattopadhyay, Vinod Kumar i William Spotz. "Next-Generation Multiphase Flow Solver for Fluidized Bed Applications". W ASME 2017 Fluids Engineering Division Summer Meeting. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/fedsm2017-69555.
Pełny tekst źródłaStreszczenie:
A framework is developed to integrate MFiX (Multiphase Flow with Interphase eXchanges) with advanced linear solvers in Trilinos. MFiX is a widely used open source general purpose multiphase solver developed by National Energy Technology Laboratories and written in Fortran. Trilinos is an objected-oriented open source software development platform from Sandia National Laboratories for solving large scale multiphysics problems. The framework handles the different data structures in Fortran and C++ and exchanges the information from MFiX to Trilinos and vice versa. The integrated solver, called MFiX-Trilinos hereafter, provides next-generation computational capabilities including scalable linear solvers for distributed memory massively parallel computers. In this paper, the solution from the standard linear solvers in MFiX-Trilinos is validated against the same from MFiX for 2D and 3D fluidized bed problems. The standard iterative solvers considered in this work are Bi-Conjugate Gradient Stabilized (BiCGStab) and Generalized minimal residual methods (GMRES) as the matrix is non-symmetric in nature. The stopping criterion set for the iterative solvers is same. It is observed that the solution from the integrated solver and MFiX is in good agreement.
4
Varadarajan, P. A., i P. S. Hammond. "Flux corrected transport solver for solving 1D multiphase equations for drilling applications". W MULTIPHASE FLOW 2013. Southampton, UK: WIT Press, 2013. http://dx.doi.org/10.2495/mpf130151.
Pełny tekst źródła
5
Rambaks, Andris, Hubertus Murrenhoff i Katharina Schmitz. "A MULTIPHASE, RIEMANN-SOLVER APPROACH TO GAS-CAVITATION". W 5th Thermal and Fluids Engineering Conference (TFEC). Connecticut: Begellhouse, 2020. http://dx.doi.org/10.1615/tfec2020.mph.031923.
Pełny tekst źródła
6
Akhtar, M. Wasy, i Holley C. Love. "Computations of Single and Multiphase Flows Using a Lattice Boltzmann Solver". W ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93817.
Pełny tekst źródłaStreszczenie:
Abstract There is considerable interest in high fidelity simulation of both single phase incompressible flows and multiphase flows. Most commonly applied numerical methods include finite difference, finite volume, finite element and spectral methods. All of these methods attempt to capture the flow details by solving the Navier–Stokes equations. Challenges of solving the Navier–Stokes single phase incompressible flows include the non-locality of the pressure gradient, non-linearity of the advection term and handling the pressure-velocity coupling. Multiphase flow computations pose additional challenges, such as property and flow variable discontinuities at the interface, whose location and orientation is not known a priori. Further, capturing/tracking of the multiphase interface requires solution of an additional advection equation. Recently, the lattice Boltzmann method has been applied to compute fluid dynamics simulations both for single and multiphase configurations; it is considered a modern CFD approach with improved accuracy and performance. Specifically, we employ a multiple-relaxation time (MRT) technique for the collision term on a D3Q27 lattice. The multiphase interface is captured using the phase-field approach of Allen-Cahn. Test cases include lid driven cavity, vortex shedding for a double backward facing step, Rayleigh Taylor instability, Enright’s deformation test and rising bubble in an infinite domain. These test cases validate different aspects of the single and multiphase model, so that the results can be interpreted with confidence that the underlying computational framework is sufficiently accurate.
7
Li, Huiying, i Sergio A. Vasquez. "Numerical Simulation of Steady and Unsteady Compressible Multiphase Flows". W ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-87928.
Pełny tekst źródłaStreszczenie:
The present work concerns the development of an advanced numerical approach to simulate steady and unsteady compressible multiphase flows in the CFD solver FLUENT. Compressible multiphase flows can be simulated under the framework of either the multiphase Mixture/VOF or the Eulerian multifluid model. The governing equations solved are the mixture (Mixture or VOF model) or phase (Eulerian multifluid model) momentum, energy, species transport equations and phase volume fraction equations. Turbulence effects are accounted for using a range of multiphase turbulence models. For the compressible multiphase model, it assumes that only one phase is a compressible gas/gaseous mixture with multiple species. In gas-liquid flows, all the liquid phases can be compressible /incompressible liquid, while in gas-solid flows the solid phase can be treated as a granular flow. To ensure numerical stability and obtain physical solutions, the absolute pressure is limited in a way to satisfy the constraints for both incompressible and compressible flows that may exist in different regions. The compressible effects are taken into account by adding extra terms related to sound speed and phase volume fractions in both the phase volume fraction and the pressure-correction equations. For flow conditions at inlets and exits, only pressure and mass-flow-rate boundaries are applicable. The mixture Mach numbers are defined and used to determine the subsonic or supersonic flows and thermal boundary conditions. The compressible multiphase model have been successfully used to simulate steady and unsteady, sub- and super-sonic compressible multiphase flows in a wide range of 2D and 3D multiphase systems. The examples presented in the paper include: (1). Gas-liquid separation in a vertical cylindrical container; (2). Transient pressure variations in compressible liquid and gas-liquid flows of water hammers; (3). Sub- and super-sonic gas-liquid two-phase flows in a nozzle; (4). Cavitating and ventilated super-cavitating flows; and (5). 3D gas-liquid flows in a three-stream injector. The solver robustness and convergence performance will be discussed. The solutions will be compared with available experimental data or numerical solutions. Emphasis will be focused on the solver performances on simulations of compressible multiphase flows. Overall, the results obtained from the present compressible multiphase model are in line with analytical/CFD solutions or available experimental data. The numerical approach is reasonably fast and robust, and suitable for practical compressible multiphase applications.
8
Lagumbay, Randy S., Oleg V. Vasilyev, Andreas Haselbacher i Jin Wang. "Numerical Simulation of a High Pressure Supersonic Multiphase Jet Flow Through a Gaseous Medium". W ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-61008.
Pełny tekst źródłaStreszczenie:
Computational Fluid Dynamics (CFD) analysis is used to numerically study the structure and dynamics of a high-pressure, high-speed jet of a gas/liquid mixture through a gaseous medium close to the nozzle region. The complex structure of the jet near the nozzle region is captured before it breaks-up downstream. A new multiphase model based on a mixture formulation of the conservation laws for a multiphase flows is used in the simulation. The model does not require ad-hoc closure for the variation of mixture density with pressure and yields thermodynamically accurate acoustic propagation for multiphase mixtures. The numerical formulation has been implemented to a multi-physics unstructured code “RocfluMP” that solves the modified three-dimensional time-dependent Euler/Navier-Stokes equations for a multiphase framework in integral form. The Roe’s approximate Riemann solver is used to allow capturing of shock waves and contact discontinuities. For a very steep gradient, an HLLC scheme is used to resolved the isolated shock and contact waves. The developed flow solver provides a general coupled incompressible-compressible multiphase framework that can be applied to a variety of supersonic jet flow problems including fuel injection systems, thermal and plasma spray coating, and liquid-jet machining. Preliminary results for shock tube analysis and gas/liquid free surface jet flow through a gaseous medium are presented and discussed.
9
Hosangadi, A., R. Lee, B. York, N. Sinha i S. Dash. "A three-dimensional unstructured flow solver for reacting multiphase propulsive flows". W 33rd Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1995. http://dx.doi.org/10.2514/6.1995-258.
Pełny tekst źródła
10
Lee, R., A. Hosangadi, B. York, N. Sinha i S. Dash. "Applications of an unstructured solver to reactive, multiphase plume/propulsive flowfields". W 32nd Joint Propulsion Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1996. http://dx.doi.org/10.2514/6.1996-2955.
Pełny tekst źródłaRaporty organizacyjne na temat "Multiphase Solver"
1
Park, HeeHo Daniel. Innovative Linear and Nonlinear Solvers for Simulating Multiphase Flow within Large-Scale Engineered Subsurface Systems. Office of Scientific and Technical Information (OSTI), październik 2019. http://dx.doi.org/10.2172/1570403.
Pełny tekst źródła