application of multiphase flow modeling techniques to the...
TRANSCRIPT
Application of multiphase flowmodeling techniques to the
transport of submerged mineralwool fibers
Gregory Cartland-Glover and Eckhard Krepper
Institut fur Sicherheitsforschung
Soren Alt and Wolfgang Kastner
Institut fur Proßtechnik, Prozessautomatisierung und Meßtechnik
11th July 2007
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sump
I Fine particles can remain suspended for several days, whilstheavier particles descend to the base of the sump
I Water jets and recirculation pumps cause wetted fibres andagglomerated particles to be transported to strainers and pumps
I Increases in pressure drop across the strainers can exceed pumpspecifications
I Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sumpI Fine particles can remain suspended for several days, whilst
heavier particles descend to the base of the sumpI Water jets and recirculation pumps cause wetted fibres and
agglomerated particles to be transported to strainers and pumpsI Increases in pressure drop across the strainers can exceed pump
specificationsI Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sump
I Fine particles can remain suspended for several days, whilstheavier particles descend to the base of the sump
I Water jets and recirculation pumps cause wetted fibres andagglomerated particles to be transported to strainers and pumps
I Increases in pressure drop across the strainers can exceed pumpspecifications
I Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sumpI Fine particles can remain suspended for several days, whilst
heavier particles descend to the base of the sump
I Water jets and recirculation pumps cause wetted fibres andagglomerated particles to be transported to strainers and pumps
I Increases in pressure drop across the strainers can exceed pumpspecifications
I Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sumpI Fine particles can remain suspended for several days, whilst
heavier particles descend to the base of the sumpI Water jets and recirculation pumps cause wetted fibres and
agglomerated particles to be transported to strainers and pumps
I Increases in pressure drop across the strainers can exceed pumpspecifications
I Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sumpI Fine particles can remain suspended for several days, whilst
heavier particles descend to the base of the sumpI Water jets and recirculation pumps cause wetted fibres and
agglomerated particles to be transported to strainers and pumpsI Increases in pressure drop across the strainers can exceed pump
specifications
I Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Debris generation and transport in BWR and PWR
I Typical particles include paint chips, metal casings, lost tools andmineral wool fibres
I Generated by LOCA steam jets destroying insulation material onlocal infrastructure
I Transported to the wetwell pool in the containment sumpI Fine particles can remain suspended for several days, whilst
heavier particles descend to the base of the sumpI Water jets and recirculation pumps cause wetted fibres and
agglomerated particles to be transported to strainers and pumpsI Increases in pressure drop across the strainers can exceed pump
specificationsI Can quickly compromise the defense-in-depth concept
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 1 / 16
Introduction Numerical Models Results Conclusions Future Work
Project Scope
I Particle debris generation by steamblasting
I Terminal velocity and sinkingcharacteristics in a vertical column
I Sedimentation and resuspension ofsubmerged particles in a horizontal flow
I Pressure drop analysis with theaccumulation of particles infilters/strainers
I Multiphase water jet injection
I Scale-up to containment sump scale
with
+ typical geometries+ multiphase interactions and
phenomena+ equipment (pumps, filters, etc)
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 2 / 16
Introduction Numerical Models Results Conclusions Future Work
Project Scope
I Particle debris generation by steamblasting
I Terminal velocity and sinkingcharacteristics in a vertical column
I Sedimentation and resuspension ofsubmerged particles in a horizontal flow
I Pressure drop analysis with theaccumulation of particles infilters/strainers
I Multiphase water jet injection
I Scale-up to containment sump scale
with
+ typical geometries+ multiphase interactions and
phenomena+ equipment (pumps, filters, etc)
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 2 / 16
Introduction Numerical Models Results Conclusions Future Work
Project Scope
I Particle debris generation by steamblasting
I Terminal velocity and sinkingcharacteristics in a vertical column
I Sedimentation and resuspension ofsubmerged particles in a horizontal flow
I Pressure drop analysis with theaccumulation of particles infilters/strainers
I Multiphase water jet injection
I Scale-up to containment sump scale
with
+ typical geometries+ multiphase interactions and
phenomena+ equipment (pumps, filters, etc)
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 2 / 16
Introduction Numerical Models Results Conclusions Future Work
Project Scope
I Particle debris generation by steamblasting
I Terminal velocity and sinkingcharacteristics in a vertical column
I Sedimentation and resuspension ofsubmerged particles in a horizontal flow
I Pressure drop analysis with theaccumulation of particles infilters/strainers
I Multiphase water jet injection
I Scale-up to containment sump scale
with
+ typical geometries+ multiphase interactions and
phenomena+ equipment (pumps, filters, etc)
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 2 / 16
Introduction Numerical Models Results Conclusions Future Work
Project Scope
I Particle debris generation by steamblasting
I Terminal velocity and sinkingcharacteristics in a vertical column
I Sedimentation and resuspension ofsubmerged particles in a horizontal flow
I Pressure drop analysis with theaccumulation of particles infilters/strainers
I Multiphase water jet injection
I Scale-up to containment sump scale
with
+ typical geometries+ multiphase interactions and
phenomena+ equipment (pumps, filters, etc)
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 2 / 16
Introduction Numerical Models Results Conclusions Future Work
Project Scope
I Particle debris generation by steamblasting
I Terminal velocity and sinkingcharacteristics in a vertical column
I Sedimentation and resuspension ofsubmerged particles in a horizontal flow
I Pressure drop analysis with theaccumulation of particles infilters/strainers
I Multiphase water jet injection
I Scale-up to containment sump scale
with
+ typical geometries+ multiphase interactions and
phenomena+ equipment (pumps, filters, etc)
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 2 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses
+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine
+ Whole channel+ Channel section upstream
of the impeller+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video
+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine
+ Whole channel+ Channel section upstream
of the impeller+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity
+ Pertinent concentrations
I Numerical study can
examine
+ Whole channel+ Channel section upstream
of the impeller+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine
+ Whole channel+ Channel section upstream
of the impeller+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine+ Whole channel
+ Channel section upstreamof the impeller
+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine+ Whole channel+ Channel section upstream
of the impeller
+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine+ Whole channel+ Channel section upstream
of the impeller+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Study of sedimentation and resuspension of submergedparticles in a horizontal flow
I Experimental study uses+ Laser PIV+ High-speed video+ Ultrasound velocity+ Turbidity+ Pertinent concentrations
I Numerical study can
examine+ Whole channel+ Channel section upstream
of the impeller+ Flow disruption by baffles
I To determine the impact
of+ Local velocity field+ Local concentration
profiles+ Viscosity+ Buoyancy, drag and
turbulence dispersionforces
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 3 / 16
Introduction Numerical Models Results Conclusions Future Work
Overview of numerical models used
I Eulerian-Eulerian multiphase flow
I SST turbulence
I Virtual particle (1)I Viscosity closure models (2) to (7)
+ Relative and mixture (2) and (3)+ Dispersed phase eddy viscosity (4)+ Continuous phase eddy viscosity (5) and (6)
I Interphase forces (7) to (12)+ Buoyancy (7)+ Drag (8)+ Turbulent Dispersion (9)
I Boundary and initial conditions+ Low velocity, sedimenting conditions+ Medium velocity, sedimenting and resuspending conditions+ High velocity, transport of solids with little sedimentation
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 4 / 16
Introduction Numerical Models Results Conclusions Future Work
Overview of numerical models used
I Eulerian-Eulerian multiphase flow
I SST turbulence
I Virtual particle (1)I Viscosity closure models (2) to (7)
+ Relative and mixture (2) and (3)+ Dispersed phase eddy viscosity (4)+ Continuous phase eddy viscosity (5) and (6)
I Interphase forces (7) to (12)+ Buoyancy (7)+ Drag (8)+ Turbulent Dispersion (9)
I Boundary and initial conditions+ Low velocity, sedimenting conditions+ Medium velocity, sedimenting and resuspending conditions+ High velocity, transport of solids with little sedimentation
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 4 / 16
Introduction Numerical Models Results Conclusions Future Work
Overview of numerical models used
I Eulerian-Eulerian multiphase flow
I SST turbulence
I Virtual particle (1)
I Viscosity closure models (2) to (7)+ Relative and mixture (2) and (3)+ Dispersed phase eddy viscosity (4)+ Continuous phase eddy viscosity (5) and (6)
I Interphase forces (7) to (12)+ Buoyancy (7)+ Drag (8)+ Turbulent Dispersion (9)
I Boundary and initial conditions+ Low velocity, sedimenting conditions+ Medium velocity, sedimenting and resuspending conditions+ High velocity, transport of solids with little sedimentation
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 4 / 16
Introduction Numerical Models Results Conclusions Future Work
Overview of numerical models used
I Eulerian-Eulerian multiphase flow
I SST turbulence
I Virtual particle (1)I Viscosity closure models (2) to (7)
+ Relative and mixture (2) and (3)+ Dispersed phase eddy viscosity (4)+ Continuous phase eddy viscosity (5) and (6)
I Interphase forces (7) to (12)+ Buoyancy (7)+ Drag (8)+ Turbulent Dispersion (9)
I Boundary and initial conditions+ Low velocity, sedimenting conditions+ Medium velocity, sedimenting and resuspending conditions+ High velocity, transport of solids with little sedimentation
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 4 / 16
Introduction Numerical Models Results Conclusions Future Work
Overview of numerical models used
I Eulerian-Eulerian multiphase flow
I SST turbulence
I Virtual particle (1)I Viscosity closure models (2) to (7)
+ Relative and mixture (2) and (3)+ Dispersed phase eddy viscosity (4)+ Continuous phase eddy viscosity (5) and (6)
I Interphase forces (7) to (12)+ Buoyancy (7)+ Drag (8)+ Turbulent Dispersion (9)
I Boundary and initial conditions+ Low velocity, sedimenting conditions+ Medium velocity, sedimenting and resuspending conditions+ High velocity, transport of solids with little sedimentation
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 4 / 16
Introduction Numerical Models Results Conclusions Future Work
Overview of numerical models used
I Eulerian-Eulerian multiphase flow
I SST turbulence
I Virtual particle (1)I Viscosity closure models (2) to (7)
+ Relative and mixture (2) and (3)+ Dispersed phase eddy viscosity (4)+ Continuous phase eddy viscosity (5) and (6)
I Interphase forces (7) to (12)+ Buoyancy (7)+ Drag (8)+ Turbulent Dispersion (9)
I Boundary and initial conditions+ Low velocity, sedimenting conditions+ Medium velocity, sedimenting and resuspending conditions+ High velocity, transport of solids with little sedimentation
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 4 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
The virtual particle
I Particles can be
classified by
+ sphericity+ compactness+ convexity
Class Particles
1
2
3
4
5
I Measured distribution ofagglomerate velocities
I Mean terminal velocity of particles0.05 m s−1
I Assumed spherical agglomerate offibres
I Drag = Buoyancy
I Iteratively resolve CD
I Terminal velocity ≡ measured
mean velocities was obtained
+ dp = 5 mm
+ ρc = 997 kg m−3
+ ρf = 2800 kg m−3
+ ρp = 1030 kg m−3
I This also gives a particle share of0.018
αp =ρp − ρcρf − ρc
(1)
d = diameter; α = particle share; ρ = density; Subscripts: c = continuous; p = dispersed; f = fibre;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 5 / 16
Introduction Numerical Models Results Conclusions Future Work
Molecular Viscosities
I Mixture viscosityµcp = µcµr (2)
I Relative viscosity
µr1 = 1 +
{0 rp < 0.6
r3p104 rp ≥ 0.6
(3a)
µr2 =
(1−
rp
rpmax
)−µinrpmax
(3b)
µr3 = 1 + µinrp + Chydr2p (3c)
Chyd = hydrodynamic constant = 6.2; r = volume fraction; µ = dynamic viscosity; µin = intrinsic viscosity = 2.5; Subscripts: c =continuous; cp = mixture; r = relative; p = dispersed; pmax = maximum dispersed phase fraction;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 6 / 16
Introduction Numerical Models Results Conclusions Future Work
Molecular Viscosities
I Mixture viscosityµcp = µcµr (2)
I Relative viscosity
µr1 = 1 +
{0 rp < 0.6
r3p104 rp ≥ 0.6
(3a)
µr2 =
(1−
rp
rpmax
)−µinrpmax
(3b)
µr3 = 1 + µinrp + Chydr2p (3c)
Chyd = hydrodynamic constant = 6.2; r = volume fraction; µ = dynamic viscosity; µin = intrinsic viscosity = 2.5; Subscripts: c =continuous; cp = mixture; r = relative; p = dispersed; pmax = maximum dispersed phase fraction;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 6 / 16
Introduction Numerical Models Results Conclusions Future Work
Eddy Viscosities
I Dispersed phase eddy viscosity, where ν = µ/ρ
νtp =νtc
σtc(4)
I Continuous phase eddy viscosity
νtc = cµk2c
εc(5a)
νtc =c0.5µ kc
fmax
(c0.5µ ωc, 2τij tanh
[fmax
(2k0.5c
cµωcy, 500νcy2ωc
)2]) (5b)
τij =1
2
(∂Ui
∂xj+∂Uj
∂xi
)(6)
Cµ = turbulence constant = 0.09; fmax = maximum function; k = turbulent kinetic energy; U = mean velocity vector component; x= position vector component; y = distance to nearest wall; ε = eddy dissipation rate; ν = kinematic viscosity; σ = turbulent Prandtl
number; τ = shear rate tensor; ω = eddy frequency; Subscripts: c = continuous; i = ith direction vector component; j = jth directionvector component; p = dispersed; t = turbulent eddy;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
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Introduction Numerical Models Results Conclusions Future Work
Eddy Viscosities
I Dispersed phase eddy viscosity, where ν = µ/ρ
νtp =νtc
σtc(4)
I Continuous phase eddy viscosity
νtc = cµk2c
εc(5a)
νtc =c0.5µ kc
fmax
(c0.5µ ωc, 2τij tanh
[fmax
(2k0.5c
cµωcy, 500νcy2ωc
)2]) (5b)
τij =1
2
(∂Ui
∂xj+∂Uj
∂xi
)(6)
Cµ = turbulence constant = 0.09; fmax = maximum function; k = turbulent kinetic energy; U = mean velocity vector component; x= position vector component; y = distance to nearest wall; ε = eddy dissipation rate; ν = kinematic viscosity; σ = turbulent Prandtl
number; τ = shear rate tensor; ω = eddy frequency; Subscripts: c = continuous; i = ith direction vector component; j = jth directionvector component; p = dispersed; t = turbulent eddy;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 7 / 16
Introduction Numerical Models Results Conclusions Future Work
Interphase forces
I Buoyancy force characterises the motion of the particles
SBcp = grp (ρp − ρc) (7)
I Drag Force characterises the resistance of the particles to fluidflow
MDcp = CD
cp (Up −Uc) (8)
I Turbulent dispersion force characterises the response and spreadof particles due to turbulent eddies
MTDcp = CTDC
Dcp
νtc
σtc
(∇rprp−∇rcrc
)(9)
CDcp = momentum exchange coefficient; CTD = turbulence dispersion coefficient; g = gravitational acceleration; M = interfacial
force; r = volume fraction; S = body or external force; U = mean velocity vector; ν = kinematic viscosity; ρ = density; σ = turbulentPrandtl number; Subscripts: c = continuous; cp = mixture; p = dispersed; t = turbulent eddy; Superscripts: B = buoyancy; D = drag;TD = turbulence dispersion
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 8 / 16
Introduction Numerical Models Results Conclusions Future Work
Interphase forces
I Buoyancy force characterises the motion of the particles
SBcp = grp (ρp − ρc) (7)
I Drag Force characterises the resistance of the particles to fluidflow
MDcp = CD
cp (Up −Uc) (8)
I Turbulent dispersion force characterises the response and spreadof particles due to turbulent eddies
MTDcp = CTDC
Dcp
νtc
σtc
(∇rprp−∇rcrc
)(9)
CDcp = momentum exchange coefficient; CTD = turbulence dispersion coefficient; g = gravitational acceleration; M = interfacial
force; r = volume fraction; S = body or external force; U = mean velocity vector; ν = kinematic viscosity; ρ = density; σ = turbulentPrandtl number; Subscripts: c = continuous; cp = mixture; p = dispersed; t = turbulent eddy; Superscripts: B = buoyancy; D = drag;TD = turbulence dispersion
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 8 / 16
Introduction Numerical Models Results Conclusions Future Work
Interphase forces
I Buoyancy force characterises the motion of the particles
SBcp = grp (ρp − ρc) (7)
I Drag Force characterises the resistance of the particles to fluidflow
MDcp = CD
cp (Up −Uc) (8)
I Turbulent dispersion force characterises the response and spreadof particles due to turbulent eddies
MTDcp = CTDC
Dcp
νtc
σtc
(∇rprp−∇rcrc
)(9)
CDcp = momentum exchange coefficient; CTD = turbulence dispersion coefficient; g = gravitational acceleration; M = interfacial
force; r = volume fraction; S = body or external force; U = mean velocity vector; ν = kinematic viscosity; ρ = density; σ = turbulentPrandtl number; Subscripts: c = continuous; cp = mixture; p = dispersed; t = turbulent eddy; Superscripts: B = buoyancy; D = drag;TD = turbulence dispersion
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 8 / 16
Introduction Numerical Models Results Conclusions Future Work
Key terms in drag and turbulent dispersion forces
I Eddy diffusivity hypothesis resolves the spread of volume fraction by velocityfluctuations
r′ku′k =
νtk
σtk∇rk (10)
I Analogous to eddy viscosity hypothesis
u′ku′k = νtk∇uk (11)
I CDcp = momentum exchange coefficient
CDcp =3
4
CD
dprpρc |Up −Uc| (12a)
CD =
24Rep
Rep � 124Rep
(1 + 0.15Re0.687p
)1 < Rep < 103
0.44 103 < Rep < 2 ∗ 105
(12b)
Rep =dpUnp
νc(12c)
UTp =
√4
3gρp − ρcρc
dp1
CD(12d)
CD = drag coefficient; d = particle diameter; Re = Reynolds number; r = volume fraction; r′ = fluctuating volume fraction; U =
mean velocity vector; u′ = fluctuating velocity vector; ν = kinematic viscosity; ρ = density; σ = turbulent Prandtl number; Subscripts:c = continuous; cp = mixture; p = dispersed; t = turbulent eddy; T = terminal settling velocity
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 9 / 16
Introduction Numerical Models Results Conclusions Future Work
Key terms in drag and turbulent dispersion forces
I Eddy diffusivity hypothesis resolves the spread of volume fraction by velocityfluctuations
r′ku′k =
νtk
σtk∇rk (10)
I Analogous to eddy viscosity hypothesis
u′ku′k = νtk∇uk (11)
I CDcp = momentum exchange coefficient
CDcp =3
4
CD
dprpρc |Up −Uc| (12a)
CD =
24Rep
Rep � 124Rep
(1 + 0.15Re0.687p
)1 < Rep < 103
0.44 103 < Rep < 2 ∗ 105
(12b)
Rep =dpUnp
νc(12c)
UTp =
√4
3gρp − ρcρc
dp1
CD(12d)
CD = drag coefficient; d = particle diameter; Re = Reynolds number; r = volume fraction; r′ = fluctuating volume fraction; U =
mean velocity vector; u′ = fluctuating velocity vector; ν = kinematic viscosity; ρ = density; σ = turbulent Prandtl number; Subscripts:c = continuous; cp = mixture; p = dispersed; t = turbulent eddy; T = terminal settling velocity
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 9 / 16
Introduction Numerical Models Results Conclusions Future Work
Key terms in drag and turbulent dispersion forces
I Eddy diffusivity hypothesis resolves the spread of volume fraction by velocityfluctuations
r′ku′k =
νtk
σtk∇rk (10)
I Analogous to eddy viscosity hypothesis
u′ku′k = νtk∇uk (11)
I CDcp = momentum exchange coefficient
CDcp =3
4
CD
dprpρc |Up −Uc| (12a)
CD =
24Rep
Rep � 124Rep
(1 + 0.15Re0.687p
)1 < Rep < 103
0.44 103 < Rep < 2 ∗ 105
(12b)
Rep =dpUnp
νc(12c)
UTp =
√4
3gρp − ρcρc
dp1
CD(12d)
CD = drag coefficient; d = particle diameter; Re = Reynolds number; r = volume fraction; r′ = fluctuating volume fraction; U =
mean velocity vector; u′ = fluctuating velocity vector; ν = kinematic viscosity; ρ = density; σ = turbulent Prandtl number; Subscripts:c = continuous; cp = mixture; p = dispersed; t = turbulent eddy; T = terminal settling velocity
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 9 / 16
Introduction Numerical Models Results Conclusions Future Work
Effect of relative viscosity
Horizontal velocity of continuous phase
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.00 0.01 0.02 0.03 0.04 0.05
z(m
)
Horizontal Component of Uc (m s−1)
TDF = 0; ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.00 0.02 0.04 0.06 0.08 0.10 0.12
z(m
)
Horizontal Component of Uc (m s−1)
TDF = 0; ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.30 0.35 0.40 0.45 0.50 0.55 0.60
z(m
)
Horizontal Component of Uc (m s−1)
TDF = 0; ReC = 1 ∗ 105
Dispersed phase volume fraction
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z(m
)
rp (-)
TDF = 0; ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z(m
)
rp (-)
TDF = 0; ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z(m
)
rp (-)
TDF = 0; ReC = 1 ∗ 105
I SST Turbulence: thick solid lines; Laminar: thin solid lines;
I Relative viscosities:
Red :µr1 = 1 +
{0 rp < 0.6
r3p104 rp ≥ 0.6
; Blue : µr2 =
(1− rp
rpmax
)−µinrpmax; Black: µr3 = 1 + µinrp + Chydr
2p;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 10 / 16
Introduction Numerical Models Results Conclusions Future Work
Effect of coefficient of turbulence dispersion (1)
Horizontal velocity of continuous phase
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.00 0.01 0.02 0.03 0.04 0.05
z(m
)
Horizontal Component of Uc (m s−1)
ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.00 0.02 0.04 0.06 0.08 0.10 0.12
z(m
)
Horizontal Component of Uc (m s−1)
ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.30 0.35 0.40 0.45 0.50 0.55 0.60
z(m
)
Horizontal Component of Uc (m s−1)
ReC = 1 ∗ 105
Dispersed phase volume fraction
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z(m
)
rp (-)
ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z(m
)
rp (-)
ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
z(m
)
rp (-)
ReC = 1 ∗ 105
I Coefficient of turbulent dispersion: TDF = 0: thick black solid lines; TDF = 1: thick red lines; TDF = 50: thick blue solid lines;TDF = 100: thick cyan solid lines; Laminar: thin black solid lines;
I Relative viscosity: µr2 =
(1− rp
rpmax
)−µinrpmax;
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Introduction Numerical Models Results Conclusions Future Work
Effect of coefficient of turbulence dispersion (2)
Product of eddy diffusivity and volume fraction gradient
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−12 10−6 100 106 1012
z(m
)
(νtc
σtc
∇rp
rp
)(m s−1)
ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−12 10−6 100 106 1012
z(m
)
(νtc
σtc
∇rp
rp
)(m s−1)
ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−12 10−6 100 106 1012
z(m
)
(νtc
σtc
∇rp
rp
)(m s−1)
ReC = 1 ∗ 105
Momentum exchange coefficient
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−12 10−6 100 106
z(m
)
CDcp (kg m−3 s−1)
ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−12 10−6 100 106
z(m
)
CDcp (kg m−3 s−1)
ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−12 10−6 100 106
z(m
)
CDcp (kg m−3 s−1)
ReC = 1 ∗ 105
I Coefficient of turbulent dispersion: TDF = 0: thick black solid lines; TDF = 1: thick red lines; TDF = 50: thick blue solid lines;TDF = 100: thick cyan solid lines; Laminar: thin black solid lines;
I Relative viscosity: µr2 =
(1− rp
rpmax
)−µinrpmax;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 12 / 16
Introduction Numerical Models Results Conclusions Future Work
Effect of coefficient of turbulence dispersion (3)
Turbulence dispersion force
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−4 10−2 100 102 104
z(m
)
MTDcp (kg m−2 s−2)
ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
10−4 10−2 100 102 104
z(m
)
MTDcp (kg m−2 s−2)
ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0 20 40 60 80 100 120
z(m
)
MTDcp (kg m−2 s−2)
ReC = 1 ∗ 105
Buoyancy force
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
−400 −300 −200 −100 0
z(m
)
SBcp (kg m−2 s−2)
ReA = 4 ∗ 103
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
−400 −300 −200 −100 0
z(m
)
SBcp (kg m−2 s−2)
ReB = 2 ∗ 104
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
−400 −300 −200 −100 0
z(m
)
SBcp (kg m−2 s−2)
ReC = 1 ∗ 105
I Coefficient of turbulent dispersion: TDF = 0: thick black solid lines; TDF = 1: thick red lines; TDF = 50: thick blue solid lines;TDF = 100: thick cyan solid lines; Laminar: thin black solid lines;
I Relative viscosity: µr2 =
(1− rp
rpmax
)−µinrpmax;
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 13 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Conclusions
I Qualitatively correct phenomena observed at different velocityconditions
I Selected relative viscosity correlations show no significant effects
I Requires a modified turbulent dispersion force to give qualitativephenomena
I Modification made through CTD
I Influence of momentum exchange on the turbulence dispersionforce is shown at higher velocities
I Influence of viscosity is strongest in the particulate layer at lowervelocities
I Direct experiments to gain further information on the transportproperties of the particles
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 14 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Future Work
I Acquire experimental data to select and validate applied closure andinterfacial force models
I Use higher velocities to measure turbulence dispersion force
I To resolve the momentum exchange term+ Particle description+ Particle drag coefficient+ Particle contact area
I Relative viscosity has an influence at lower velocities and higher volume
fractions+ Particle shape and orientation+ Intrinsic viscosity+ Volume fraction dependency
I Modify flow by introducing baffles
I Scale-up to containment vessel size
I Increase complexity+ Particle size and shape distributions+ Agglomeration and fragmentation models+ Multiphase interactions (gas-liquid-solid) with descending hot water jets
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 15 / 16
Introduction Numerical Models Results Conclusions Future Work
Acknowledgments
I Project partners:+ IPM Zittau
Thoralf Gocht, Rainer Hampel, Alexander Kratzsch, StefanRenger, Andre Seeliger and Frank Zacharias
+ FZDAlexander Grahn
I German Federal Ministry of Economy and Labor Contracts No.1501270 and 1501307
Institut fur SicherheitsforschungMitglied der Leibniz-Gemeinschaft
Cartland-Glover, Alt, Kastner &Krepper 16 / 16