D3q27 pf velocity

Description

The 'd3q27_pf_velocity' model is a multiphase 3D lattice Boltzmann model for the simulation of immiscible fluids (at both high and low density ratios).

The base implementation uses a velocity based LBM for capturing the hydrodynamics of the flow and solves the conservative phase field equation for the interfacial dynamics. To enhance stability, a Weighted-Multiple-Relaxation-Time collision operator is used.

The model currently has 3 options at compile time: - OutFlow; this enables convective and neumann outflow conditions. It requires extra memory access and is thus added as a compile option (faster code without). - BGK; this is in existence for the sole reason of initial testing, however if you would like to use a BGK collision operator - this flag is necessary. - autosym; both of these options can be compiled with symmetry conditions.

Details

Model description files files for this model: Dynamics.c Dynamics.R

Zonal Settings

Name Comment
PhaseField Initial PhaseField distribution
VelocityX inlet/outlet/init velocity
VelocityY inlet/outlet/init velocity
VelocityZ inlet/outlet/init velocity
Pressure inlet/outlet/init density
InterfacePositionInObj Weight of [trackPosition] in objective
VfrontInObj Weight of [velocity infront of bubble] in objective
VbackInObj Weight of [velocity behind bubble] in objective
RTISpikeInObj Weight of [SpikeTracker ] in objective
RTIBubbleInObj Weight of [BubbleTracker] in objective
RTISaddleInObj Weight of [SaddleTracker] in objective
PressureLossInObj Weight of [pressure loss] in objective
OutletFluxInObj Weight of [pressure loss] in objective
InletFluxInObj Weight of [pressure loss] in objective
TotalDensityInObj Weight of [Mass conservation check] in objective
KineticEnergyInObj Weight of [Measure of kinetic energy] in objective
GasTotalVelocityInObj Weight of [use to determine avg velocity of bubbles] in objective
GasTotalVelocityXInObj Weight of [use to determine avg velocity of bubbles] in objective
GasTotalVelocityYInObj Weight of [use to determine avg velocity of bubbles] in objective
GasTotalVelocityZInObj Weight of [use to determine avg velocity of bubbles] in objective
GasCellsInObj Weight of [use in line with GasTotalVelocity to determine average velocity] in objective

Global Settings

Name Derived Comment
Density_h High density
Density_l Low density
PhaseField_h PhaseField in Liquid
PhaseField_l PhaseField gas
IntWidth Anti-diffusivity coeff
omega_phi 1.0/(3*M+0.5) one over relaxation time (phase field)
M Mobility
sigma surface tension
ContactAngle Contact angle in degrees
radAngle ContactAngle*3.1415926535897/180 Conversion to rads for calcs
RTI_Characteristic_Length Use for RTI instability
Radius Diffuse Sphere Radius
CenterX Diffuse sphere center_x
CenterY Diffuse sphere center_y
CenterZ Diffuse sphere center_z
BubbleType droplet(1.0) or bubble(-1.0)?!
DonutTime Radius of a Torus - initialised to travel along x-axis
Donut_h Half donut thickness, i.e. the radius of the cross-section
Donut_D Dilation factor along the x-axis
Donut_x0 Position along x-axis
tau_l (3*Viscosity_l) relaxation time (low density fluid)
tau_h (3*Viscosity_h) relaxation time (high density fluid)
Viscosity_l kinematic viscosity
Viscosity_h kinematic viscosity
GravitationX applied (rho)*GravitationX
GravitationY applied (rho)*GravitationY
GravitationZ applied (rho)*GravitationZ
BuoyancyX applied (rho_h-rho)*BuoyancyX
BuoyancyY applied (rho_h-rho)*BuoyancyY
BuoyancyZ applied (rho_h-rho)*BuoyancyZ
xyzTrack x<-1, y<-2, z<-3
Threshold Parameters threshold

Exported Quantities (VTK, etc)

Name Unit Comment
Rho kg/m3 Rho
PhaseField 1 PhaseField
U m/s U
P Pa P
Normal 1 Normal

Exported Global Integrals (CSV, etc)

Name Unit Comment
InterfacePosition 1 trackPosition
Vfront 1 velocity infront of bubble
Vback 1 velocity behind bubble
RTISpike 1 SpikeTracker
RTIBubble 1 BubbleTracker
RTISaddle 1 SaddleTracker
PressureLoss 1mPa pressure loss
OutletFlux 1m2/s pressure loss
InletFlux 1m2/s pressure loss
TotalDensity 1kg/m3 Mass conservation check
KineticEnergy J Measure of kinetic energy
GasTotalVelocity m/s use to determine avg velocity of bubbles
GasTotalVelocityX m/s use to determine avg velocity of bubbles
GasTotalVelocityY m/s use to determine avg velocity of bubbles
GasTotalVelocityZ m/s use to determine avg velocity of bubbles
GasCells 1 use in line with GasTotalVelocity to determine average velocity
Objective 1 Objective function

Node Types

Group Types
ADDITIONALS Centerline, Smoothing, Spiketrack, Saddletrack, Bubbletrack
BOUNDARY Wall, Solid, WVelocity, WPressure, WPressureL, EPressure, EVelocity, MovingWall_N, MovingWall_S, NVelocity
COLLISION BGK, MRT
DESIGNSPACE DesignSpace
NONE None
SETTINGZONE DefaultZone

Solved fields

Name Access pattern Comment
g0 stencil g0
g1 stencil g1
g2 stencil g2
g3 stencil g3
g4 stencil g4
g5 stencil g5
g6 stencil g6
g7 stencil g7
g8 stencil g8
g9 stencil g9
g10 stencil g10
g11 stencil g11
g12 stencil g12
g13 stencil g13
g14 stencil g14
g15 stencil g15
g16 stencil g16
g17 stencil g17
g18 stencil g18
g19 stencil g19
g20 stencil g20
g21 stencil g21
g22 stencil g22
g23 stencil g23
g24 stencil g24
g25 stencil g25
g26 stencil g26
h0 stencil h0
h1 stencil h1
h2 stencil h2
h3 stencil h3
h4 stencil h4
h5 stencil h5
h6 stencil h6
h7 stencil h7
h8 stencil h8
h9 stencil h9
h10 stencil h10
h11 stencil h11
h12 stencil h12
h13 stencil h13
h14 stencil h14
U stencil U
V stencil V
W stencil W
nw_x stencil nw_x
nw_y stencil nw_y
nw_z stencil nw_z
PhaseF stencil PhaseF

Densities - default accessors

Name Field Pulling field from Comment
g0 g0 stencil g0
g1 g1 stencil g1
g2 g2 stencil g2
g3 g3 stencil g3
g4 g4 stencil g4
g5 g5 stencil g5
g6 g6 stencil g6
g7 g7 stencil g7
g8 g8 stencil g8
g9 g9 stencil g9
g10 g10 stencil g10
g11 g11 stencil g11
g12 g12 stencil g12
g13 g13 stencil g13
g14 g14 stencil g14
g15 g15 stencil g15
g16 g16 stencil g16
g17 g17 stencil g17
g18 g18 stencil g18
g19 g19 stencil g19
g20 g20 stencil g20
g21 g21 stencil g21
g22 g22 stencil g22
g23 g23 stencil g23
g24 g24 stencil g24
g25 g25 stencil g25
g26 g26 stencil g26
h0 h0 stencil h0
h1 h1 stencil h1
h2 h2 stencil h2
h3 h3 stencil h3
h4 h4 stencil h4
h5 h5 stencil h5
h6 h6 stencil h6
h7 h7 stencil h7
h8 h8 stencil h8
h9 h9 stencil h9
h10 h10 stencil h10
h11 h11 stencil h11
h12 h12 stencil h12
h13 h13 stencil h13
h14 h14 stencil h14
U U stencil U
V V stencil V
W W stencil W
nw_x nw_x stencil nw_x
nw_y nw_y stencil nw_y
nw_z nw_z stencil nw_z

Action stages

Name Main procedure Preloaded densities Pushed fields
PhaseInit Init none PhaseF
WallInit Init_wallNorm none nw_x, nw_y, nw_z
calcWall calcWallPhase nw_x, nw_y, nw_z PhaseF
BaseInit Init_distributions none g0, g1, g2, g3, g4, g5, g6, g7, g8, g9, g10, g11, g12, g13, g14, g15, g16, g17, g18, g19, g20, g21, g22, g23, g24, g25, g26, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11, h12, h13, h14, U, V, W, PhaseF
calcPhase calcPhaseF g0, g1, g2, g3, g4, g5, g6, g7, g8, g9, g10, g11, g12, g13, g14, g15, g16, g17, g18, g19, g20, g21, g22, g23, g24, g25, g26, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11, h12, h13, h14, U, V, W, nw_x, nw_y, nw_z PhaseF
BaseIter Run g0, g1, g2, g3, g4, g5, g6, g7, g8, g9, g10, g11, g12, g13, g14, g15, g16, g17, g18, g19, g20, g21, g22, g23, g24, g25, g26, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11, h12, h13, h14, U, V, W, nw_x, nw_y, nw_z g0, g1, g2, g3, g4, g5, g6, g7, g8, g9, g10, g11, g12, g13, g14, g15, g16, g17, g18, g19, g20, g21, g22, g23, g24, g25, g26, h0, h1, h2, h3, h4, h5, h6, h7, h8, h9, h10, h11, h12, h13, h14, U, V, W, nw_x, nw_y, nw_z

Actions

Name Stages
Iteration BaseIter, calcPhase, calcWall
Init PhaseInit, WallInit, calcWall, BaseInit