Models multiphase flow

Scheuerer G. Solution algorithms and implementations strategies for Eulerian-Eulerian multiphase-flow models. Proceedings of ACFD 2000 International Conference on Applied Computational Fluid Dynamics, Beijing, 2000. 

Caia C, Minev P (2004) A finite element method for an averaged multiphase flow model. Int J Computational Fluid Dynamics 18(2) 111-123... 

The statistical description of multiphase flow is developed based on the Boltzmann theory of gases [37, 121, 93, 11, 94, 58, 61]. The fundamental variable is the particle distribution function with an appropriate choice of internal coordinates relevant for the particular problem in question. Most of the multiphase flow modeling work performed so far has focused on isothermal, non-reactive mono-disperse mixtures. However, in chemical reactor engineering the industrial interest lies in multiphase systems that include multiple particle t3q)es and reactive flow mixtures, with their associated effects of mixing, segregation and heat transfer. 

Concerning the DECOVALEX benchmarks our part of the work is restricted to isothermal conditions. Multiphase flow modeling considering non-isothermal effects is performed by the Center for Applied Geosciences (2 G) in Tubingen, Germany. 

Multiphase flow modeling in non-saturated soils requires the incorporation of the relative... 

Abstract Among the noncontinuum-based computational techniques, the lattice Boltzman method (LBM) has received considerable attention recently. In this chapter, we will briefly present the main elements of the LBM, which has evolved as a minimal kinetic method for fluid dynamics, focusing in particular, on multiphase flow modeling. We will then discuss some of its recent developments based on the multiple-relaxation-time formulation and consistent discretizatirai strategies for enhanced numerical stability, high viscosity contrasts, and density ratios for simulation of interfacial instabilities and multiphase flow problems. As examples, numerical investigations of drop collisions, jet break-up, and drop impact on walls will be presented. We will also outline some future directions for further development of the LBM for applications related to interfacial instabilities and sprays. 

The remainder of this book is organized as follows. All bioreactors have common modes of operation, which are described in Chapter 2. General gas-liquid mass transfer considerations are then summarized in Chapter 3. Various hydrodynamic and gas-liquid mass transfer measure techniques are then outlined in Chapter 4, followed by a summary of multiphase flow modeling... 

The first approach, which considers a single phase, proposes conventional multiphase flow models, such as ideal flow, dispersion, and residence time distribution models. The second approach, which takes into account two phases as bubble and emulsion, suggests different governing equations for each phase and considers a term for describing mass interchange between the two phases. 

Guillen DP, Grimmett T, Gandrik AM, Antal SP. Development of a computational multiphase flow model for Fischer Tropsch synthesis in a slurry bubble column reactor. Chem. Eng. J. 2011 176-177 83-94. 

The Role of Computational Multiphase Flow Modelling in Flow Assurance and Gas Processing... 

Major advancements in the area of gas-solid multiphase flow modelling offer substantial process improvements that have the potential to significantly improve process plant operations. 

Taitel, Y. (2001), Multiphase Flow Modeling Fundamentals and Application to Oil Producing System, Department of Fluid Mechanics and Heat Transfer, Tel Aviv University. Course held at Norwegian University of Science and Technology, September 2001. 

The structure of the transport system posed a technical challenge. Multiphase flow models have been developed for merging flow networks, where the nominal flow is in one direction from the branches of the tree (the production wells) to the root of the tree (the land facilities). However in this system, the dual export line and crossover anangement impose a diverging flow network. The closed multiphase flow loops imposed by the parallel export pipelines in the Scarab/Saffron fields required expanding the multiphase flow network solver of OLGA to diverging network. 

Another objective in the study of the application of CFD in crystallization is to simulate the particle size distribution in crystallization. In order to solve this problem, the simulation should take into account the population balance. The internal coordinates of the population balance make it difficult to utilize it in the CFD environment. In addition, differentsized particles have different hydrodynamics, which causes further complications. Wei and Garside [42] used the assumption of MSMPR and the moments of population balance to avoid the above difficulties in the simulation of precipitation. In the CFX commercial application, the MUSIC model offers a method for solving the population balance equation in CFD and defines the flow velocity of different-sized particles on the basis of the ratio of the velocity to a referencesized particle. The velocity of this reference-sized particle is then simulated using the multiphase-flow model. In this way, the problem of the different hydrodynamics of different-sized particles is solved. However, the accuracy of this model is not sufficient for it to be directly used for bubble-sized distribution only. More work is required before this model can be applied to crystallization. 

Forward and Inverse Multiphase Flow Modeling 419 Flow... 

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