A Three Dimensional Simulation of M-ICAR Process

Adopting standard k-ε turbulent model and mixture flow model, settling process and decant process was simulated using 3-d numerical simulation in M-ICAR(Mixture-Intermittently Cycle Aeration Reactor) process to analyze the changes of sludge phase volume fraction. The simulation results showed that the changes of feeding wastewater had great influence on sludge settle ability in decant process, and the position of decanter needed optimized; it had no influence on sludge settle ability in settling process. For considering the lowest hydraulic retention time, the research controlled maximum feeding wastewater for 1610m3/h. Internal recycle had no influence on sludge settle ability. Two methods were proposed: the first one, the water level of decanter was set 3.9m (sludge volume fraction of this suspended area was less than 0.05), feeding velocity was 0.07 m/s; the second, keep the water level of decanter 3.75 m, reduce feeding velocity (preliminary setting feeding velocity 0.06 m/s). The two methods had no influence on sludge settle ability.

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Instrumentation For Quantitative Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078584 ◽

1977 ◽

Vol 35 ◽

pp. 206-209

Author(s):

B. Ralph ◽

A.R. Jones

Keyword(s):

Volume Fraction ◽

Three Dimensional ◽

Two Dimensional ◽

Automatic Data ◽

Phase Volume Fraction ◽

Statistical Confidence ◽

Resultant Data ◽

Automatic Data Collection ◽

Third Dimension ◽

Evolution Of Microstructure

In all fields of microscopy there is an increasing interest in the quantification of microstructure. This interest may stem from a desire to establish quality control parameters or may have a more fundamental requirement involving the derivation of parameters which partially or completely define the three dimensional nature of the microstructure. This latter categorey of study may arise from an interest in the evolution of microstructure or from a desire to generate detailed property/microstructure relationships. In the more fundamental studies some convolution of two-dimensional data into the third dimension (stereological analysis) will be necessary.In some cases the two-dimensional data may be acquired relatively easily without recourse to automatic data collection and further, it may prove possible to perform the data reduction and analysis relatively easily. In such cases the only recourse to machines may well be in establishing the statistical confidence of the resultant data. Such relatively straightforward studies tend to result from acquiring data on the whole assemblage of features making up the microstructure. In this field data mode, when parameters such as phase volume fraction, mean size etc. are sought, the main case for resorting to automation is in order to perform repetitive analyses since each analysis is relatively easily performed.

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3D Cavitations Turbulent Transient Calculation in the Francis Turbine Model

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.2466 ◽

2012 ◽

Vol 479-481 ◽

pp. 2466-2470

Author(s):

Dun Zhang ◽

Yuan Zheng

Keyword(s):

Model Experiment ◽

Flow Model ◽

Three Dimensional ◽

Francis Turbine ◽

Two Phase ◽

Mixture Flow ◽

Phase Mixture ◽

Simulation Results ◽

Accurate Numerical Solution ◽

Turbine Model

Analysis had been carried out, based on the three-dimensional transient viscous turbulent calculation of a Francis turbine full flow field, the complete cavitations model and the two-phase mixture flow model were combined during the calculation, more accurate numerical solution had been obtained. According to the simulation results, the site and extent of cavitations in the turbine flow were reflected within the specific conditions, and were more consistent with the cavitations phenomenon observed in the model experiment, also provided a reference for the more in-depth research.

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A generalized Archie’s law for n phases

Geophysics ◽

10.1190/1.3509781 ◽

2010 ◽

Vol 75 (6) ◽

pp. E247-E265 ◽

Cited By ~ 83

Author(s):

Paul W. J. Glover

Keyword(s):

Volume Fraction ◽

Three Dimensional ◽

Three Dimensions ◽

Reservoir Rock ◽

Archie’S Law ◽

Phase Volume Fraction ◽

General Law ◽

Special Cases ◽

The Matrix ◽

Definition Of

Archie’s law has been the standard method for relating the conductivity of a clean reservoir rock to its porosity and the conductivity of its pore fluid for more than [Formula: see text]. However, it is applicable only when the matrix is nonconducting. A modified version that allows a conductive matrix was published in 2000. A generalized form of Archie’s law is studied for any number of phases for which the classical Archie’s law and modified Archie’s law for two phases are special cases. The generalized Archie’s law contains a phase conductivity, a phase volume fraction, and phase exponent for each of its [Formula: see text] phases. The connectedness of each of the phases is considered, and the principle of conservation of connectedness in a three-dimensional multiphase mixture is introduced. It is confirmed that the general law is formally the same as the classical Archie’s law and modified Archie’s law for one and two conducting phases, respectively. The classical second Archie’s law is compared with the generalized law, which leads to the definition of a saturation exponent for each phase. This process has enabled the derivation of relationships between the phase exponents and saturation exponents for each phase. The relationship between percolation theory and the generalized model is also considered. The generalized law is examined in detail for two and three phases and semiquantitatively for four phases. Unfortunately, the law in its most general form is very difficult to prove experimentally. Instead, numerical modeling in three dimensions is carried out to demonstrate that it behaves well for a system consisting of four interacting conducting phases.

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Flow Mechanism and Characteristics of Pressure-Equalizing Film Along the Surface of a Moving Underwater Vehicle

Journal of Fluids Engineering ◽

10.1115/1.4038394 ◽

2017 ◽

Vol 140 (4) ◽

Cited By ~ 7

Author(s):

Guihui Ma ◽

Fu Chen ◽

Jianyang Yu ◽

Huaping Liu

Keyword(s):

Volume Fraction ◽

Surface Film ◽

Velocity Ratio ◽

Three Dimensional ◽

Flow Characteristics ◽

Vortex Pair ◽

Lateral Force ◽

Underwater Vehicle ◽

Vehicle Interior ◽

Phase Volume Fraction

Pressure-equalizing film is a slice of air layer attached to vehicle exterior with nearly uniform inside pressure, similar to ventilated cavity in composition; it is generated through exhaust process of the inside air chamber as vehicle emerges from deep water, and can reduce the lateral force and pitching moment that vertical launched underwater vehicle suffered. In this work, the emerging process of vehicle from water with pressure-equalizing exhaust was numerically calculated to investigate the evolution and flow characteristics of the generated pressure-equalizing film along its surface. Results indicated that during the whole exhaust process, the film can be obviously classified into different sections according to the distribution of phase volume fraction or pressure. The exhaust velocity ratio and flow rate from vehicle interior chamber were also found to increase as vehicle moves. In the analysis of flow structures, vortex structures such as the horseshoe vortex, “detour-separation” vortex, and counter-rotating vortex pair (CVP) can be figured out in the region of the exhaust hole. Under the effect of re-entrant jet, water around the film tail would be entrained upstream then enter the surface film to mix with the pressure-equalizing air. It leads to the happening of the three-dimensional (3D) wall vortex in the flow field.

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Three-Phase 3D Reconstruction of a LiCoO2 Cathode via FIB-SEM Tomography

Microscopy and Microanalysis ◽

10.1017/s1431927615015640 ◽

2016 ◽

Vol 22 (1) ◽

pp. 140-148 ◽

Cited By ~ 18

Author(s):

Zhao Liu ◽

Yu-chen K. Chen-Wiegart ◽

Jun Wang ◽

Scott A. Barnett ◽

Katherine T. Faber

Keyword(s):

Focused Ion Beam ◽

Volume Fraction ◽

Ion Beam ◽

Three Dimensional ◽

Lithium Ion ◽

Silicone Resin ◽

Phase Volume Fraction ◽

Low Viscosity ◽

Three Phase ◽

Battery Degradation

AbstractThree-phase three-dimensional (3D) microstructural reconstructions of lithium-ion battery electrodes are critical input for 3D simulations of electrode lithiation/delithiation, which provide a detailed understanding of battery operation. In this report, 3D images of a LiCoO2 electrode are achieved using focused ion beam-scanning electron microscopy (FIB-SEM), with clear contrast among the three phases: LiCoO2 particles, carbonaceous phases (carbon and binder) and the electrolyte space. The good contrast was achieved by utilizing an improved FIB-SEM sample preparation method that combined infiltration of the electrolyte space with a low-viscosity silicone resin and triple ion-beam polishing. Morphological parameters quantified include phase volume fraction, surface area, feature size distribution, connectivity, and tortuosity. Electrolyte tortuosity was determined using two different geometric calculations that were in good agreement. The electrolyte tortuosity distribution versus position within the electrode was found to be highly inhomogeneous; this will lead to inhomogeneous electrode lithiation/delithiation at high C-rates that could potentially cause battery degradation.

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The Effect of the Helical Inlet Port Design and the Shrouded Inlet Valve Condition on Swirl Generation in Diesel Engine

Journal of Energy Resources Technology ◽

10.1115/1.4037941 ◽

2017 ◽

Vol 140 (3) ◽

Cited By ~ 4

Author(s):

Saleh Abo-Elfadl ◽

A. Abd El-Sabor Mohamed

Keyword(s):

Three Dimensional ◽

Great Influence ◽

Flow Characteristics ◽

Volumetric Efficiency ◽

Swirl Ratio ◽

Inlet Valve ◽

Inlet Port ◽

Engine Cylinder ◽

Port Design ◽

Dimensional Simulation

Inlet port design has a great influence on swirl generation inside the engine cylinder. In this paper, two helical inlet ports having the same helix design were suggested. The first has an upper entrance, and the second has a side entrance. With the two ports, shrouded inlet valves having different conditions of shroud and orientation angles were used. Four shroud angles were used; they are 90 deg, 120 deg, 150 deg, and 180 deg. Also, four orientation angles were used; they are 0 deg, 30 deg, 60 deg, and 90 deg. Three-dimensional simulation model using the shear stress transport k–ω model was used for predicting the air flow characteristics through the inlet port and the engine cylinder in both intake and compression strokes. The results showed that the side entrance port produces swirl ratio higher than that of the upper entrance port by about 3.5%, while the volumetric efficiency is approximately the same for both ports. For both the ports, increasing the valve shroud angle increases the swirl ratio and reduces the volumetric efficiency. The maximum increments of swirl ratio relative to the ordinary valve case occur at valve conditions of 30–150 deg, 0–180 deg, and 30–180 deg. At these valve conditions, the swirl ratio values are 6.38, 6.72, and 6.95 at intake valve close (IVC) with percentage increments of 69.2%, 78.2%, and 84.4%, respectively. The corresponding values of the volumetric efficiency are 93.6, 92.5, and 91.2, respectively, with percentage decrements of 2.84%, 4%, and 5.7%, respectively.

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A compressible multiphase flow model for violent aerated wave impact problems

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2014.0542 ◽

2014 ◽

Vol 470 (2172) ◽

pp. 20140542 ◽

Cited By ~ 12

Author(s):

Z. H. Ma ◽

D. M. Causon ◽

L. Qian ◽

C. G. Mingham ◽

H. B. Gu ◽

...

Keyword(s):

Multiphase Flow ◽

Flow Model ◽

Volume Fraction ◽

Vertical Wall ◽

Homogeneous Material ◽

Finite Volume Scheme ◽

Advection Equation ◽

Wave Impact ◽

Phase Volume Fraction ◽

Compressible Multiphase Flow

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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3-D Granular Simulation on the Process of Slope Failure and Collapse

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.378-379.489 ◽

2011 ◽

Vol 378-379 ◽

pp. 489-492 ◽

Cited By ~ 1

Author(s):

Bing Yang ◽

Jun Yang

Keyword(s):

Slope Failure ◽

Flow Model ◽

Failure Process ◽

Three Dimensional ◽

Great Influence ◽

Seismic Load ◽

Different Shapes ◽

Property Losses ◽

Granular Simulation ◽

Landslide Movement

Landslides induced by many reasons had resulted in heavy casualties and property losses. Therefore, the research on the failure process of the slope and its final accumulation state is necessary. In this paper, three-dimensional particle flow model is established in PFC3D to simulate the slope failure process, triggered by gravity and seismic load respectively, and the final accumulation state. The landslide movement passing valleys of different shapes are studied and compared. The results show that the shape of valley section has great influence for both load cases.

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