Adaptive unstructured volume remeshing – II: Application to two- and three-dimensional level-set simulations of multiphase flow

The traditional method for hydrodynamic journal bearing analysis usually applies the lubrication theory based on the Reynolds equation and suitable empirical modifications to cover turbulence, heat transfer, and cavitation. In cases of complex bearing geometries for steam and heavy-duty gas turbines this approach has its obvious restrictions in regard to detail flow recirculation, mixing, mass balance, and filling level phenomena. These limitations could be circumvented by applying a computational fluid dynamics (CFD) approach resting closer to the fundamental physical laws. The present contribution reports about the state of the art of such a fully three-dimensional multiphase-flow CFD approach including cavitation and air entrainment for high-speed turbo-machinery journal bearings. It has been developed and validated using experimental data. Due to the high ambient shear rates in bearings, the multiphase-flow model for journal bearings requires substantial modifications in comparison to common two-phase flow simulations. Based on experimental data, it is found, that particular cavitation phenomena are essential for the understanding of steam and heavy-duty type gas turbine journal bearings.

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Element-local level set method for three-dimensional dynamic crack growth

International Journal for Numerical Methods in Engineering ◽

10.1002/nme.2665 ◽

2009 ◽

Vol 80 (12) ◽

pp. 1520-1543 ◽

Cited By ~ 50

Author(s):

Qinglin Duan ◽

Jeong-Hoon Song ◽

Thomas Menouillard ◽

Ted Belytschko

Keyword(s):

Crack Growth ◽

Level Set Method ◽

Level Set ◽

Local Level ◽

Three Dimensional ◽

Dynamic Crack ◽

Dynamic Crack Growth ◽

Local Level Set

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Computing three-dimensional two-phase flows with a mass-conserving level set method

Computing and Visualization in Science ◽

10.1007/s00791-008-0106-0 ◽

2008 ◽

Vol 11 (4-6) ◽

pp. 221-235 ◽

Cited By ~ 20

Author(s):

S. P. van der Pijl ◽

A. Segal ◽

C. Vuik ◽

P. Wesseling

Keyword(s):

Level Set Method ◽

Level Set ◽

Three Dimensional ◽

Two Phase Flows ◽

Two Phase

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Three-dimensional modelling of oil sand multiphase flow in at face slurry system

International Journal of Oil Gas and Coal Technology ◽

10.1504/ijogct.2018.093957 ◽

2018 ◽

Vol 19 (1) ◽

pp. 35

Author(s):

Enzu Zheng ◽

Jozef Szymanski ◽

Chaoshi Hu

Keyword(s):

Multiphase Flow ◽

Three Dimensional ◽

Oil Sand ◽

Slurry System

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High Order Schemes on Three-Dimensional General Polyhedral Meshes — Application to the Level Set Method

Communications in Computational Physics ◽

10.4208/cicp.260511.050811a ◽

2012 ◽

Vol 12 (1) ◽

pp. 1-41 ◽

Cited By ~ 6

Author(s):

Thibault Pringuey ◽

R. Stewart Cant

Keyword(s):

Level Set ◽

Three Dimensional ◽

Unstructured Meshes ◽

High Order ◽

Convex Polyhedra ◽

Two Phase ◽

High Order Schemes ◽

Flow Problems ◽

Mixed Element ◽

Areas Of Interest

AbstractIn this article, we detail the methodology developed to construct arbitrarily high order schemes — linear and WENO — on 3D mixed-element unstructured meshes made up of general convex polyhedral elements. The approach is tailored specifically for the solution of scalar level set equations for application to incompressible two-phase flow problems. The construction of WENO schemes on 3D unstructured meshes is notoriously difficult, as it involves a much higher level of complexity than 2D approaches. This due to the multiplicity of geometrical considerations introduced by the extra dimension, especially on mixed-element meshes. Therefore, we have specifically developed a number of algorithms to handle mixed-element meshes composed of convex polyhedra with convex polygonal faces. The contribution of this work concerns several areas of interest: the formulation of an improved methodology in 3D, the minimisation of computational runtime in the implementation through the maximum use of pre-processing operations, the generation of novel methods to handle complex 3D mixed-element meshes and finally the application of the method to the transport of a scalar level set.

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A lattice Boltzmann method for immiscible multiphase flow simulations using the level set method

Journal of Computational Physics ◽

10.1016/j.jcp.2008.10.032 ◽

2009 ◽

Vol 228 (4) ◽

pp. 1139-1156 ◽

Cited By ~ 31

Author(s):

G. Thömmes ◽

J. Becker ◽

M. Junk ◽

A.K. Vaikuntam ◽

D. Kehrwald ◽

...

Keyword(s):

Multiphase Flow ◽

Lattice Boltzmann Method ◽

Level Set Method ◽

Level Set ◽

Lattice Boltzmann ◽

Flow Simulations ◽

Boltzmann Method

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Coupled Heat and Mass Transfer CFD Model for Methane Hydrate

Volume 10: Petroleum Technology ◽

10.1115/omae2015-42258 ◽

2015 ◽

Author(s):

Eugenio Turco Neto ◽

M. A. Rahman ◽

Syed Imtiaz ◽

Thiago dos Santos Pereira ◽

Fernanda Soares de Sousa

Keyword(s):

Natural Gas ◽

Multiphase Flow ◽

Gas Hydrate ◽

Gas Flow ◽

Three Dimensional ◽

Hydrate Formation ◽

Cfd Model ◽

Flow Metering ◽

Ansys Cfx ◽

Gas Hydrate Formation

The gas hydrates problem has been growing in offshore deep water condition where due to low temperature and high pressure hydrate formation becomes more favorable. Several studies have been done to predict the influence of gas hydrate formation in natural gas flow pipeline. However, the effects of multiphase hydrodynamic properties on hydrate formation are missing in these studies. The use of CFD to simulate gas hydrate formation can overcome this gap. In this study a computational fluid dynamics (CFD) model has been developed for mass, heat and momentum transfer for better understanding natural gas hydrate formation and its migration into the pipelines using ANSYS CFX-14. The problem considered in this study is a three-dimensional multiphase-flow model based on Simon Lo (2003) study, which considered the oil-dominant flow in a pipeline with hydrate formation around water droplets dispersed into the oil phase. The results obtained in this study will be useful in designing a multiphase flow metering and a pump to overcome the pressure drop caused by hydrate formation in multiphase petroleum production.

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