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Micro-Macro Modelling andSimulation of Liquid-Vapour FlowDFG - CNRS Project RO 2222/4-1
Sharp Interface Approach for Liquid-Vapour Flowwith Phase Transition
Christoph Zeiler
Institute for Applied Analysis and Numerical Simulation
February 2014
Free Boundary Value Problem in Rd
[Binninger et al.]
Bulk Phases%t + div(% v) = 0,
(% v)t + div (% v ⊗ v + p(%) I ) = 0.
Phase BoundaryJ%(v · n − σ)K = 0,J%(v · n − σ) v + p(%) nK = (d − 1)γκn,qg(%) + 0.5 (v · n − σ)2
y= −k j.
Local Well-Posedness Results_ for k = 0 see
[Benzoni-Gavage, Freistühler 2004]_ for k > 0 see
[Kabil, Rohde 2013]
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 1/21
Outline
Cut Cell Method
Exact Riemann Solver
Numerical Results
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 2/21
Cut Cell Method (joint work with C. Chalons)Basic Steps
Γ(t) Domain Ω ∈ Rd with fluid in two
phases at time t > 0_ liquid Ωliq(t),_ vapour Ωvap(t),_ curved phase boundary
Γ(t) = ∂Ωliq(t) ∩ ∂Ωvap(t).
We consider physical quantities inEuler coordinates (x, t)_ density %(x, t) > 0,_ velocity v(x, t) ∈ Rd .
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 3/21
Cut Cell Method (joint work with C. Chalons)Basic Steps
Γ(t) Domain Ω ∈ Rd with fluid in two
phases at time t > 0_ liquid Ωliq(t),_ vapour Ωvap(t),_ curved phase boundary
Γ(t) = ∂Ωliq(t) ∩ ∂Ωvap(t).
Cut (and Merge) Cell Approach:_ approximate Γ(t)→ Γh(t),
_ cut cells_ and merge, when cells are to
small.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 3/21
Cut Cell Method (joint work with C. Chalons)Basic Steps
Domain Ω ∈ Rd with fluid in twophases at time t > 0_ liquid Ωliq(t),_ vapour Ωvap(t),_ curved phase boundary
Γ(t) = ∂Ωliq(t) ∩ ∂Ωvap(t).
Cut (and Merge) Cell Approach:_ approximate Γ(t)→ Γh(t),_ cut cells
_ and merge, when cells are tosmall.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 3/21
Cut Cell Method (joint work with C. Chalons)Basic Steps
Domain Ω ∈ Rd with fluid in twophases at time t > 0_ liquid Ωliq(t),_ vapour Ωvap(t),_ curved phase boundary
Γ(t) = ∂Ωliq(t) ∩ ∂Ωvap(t).
Cut (and Merge) Cell Approach:_ approximate Γ(t)→ Γh(t),_ cut cells_ and merge, when cells are to
small.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 3/21
Cut Cell MethodMacroscale
MacroscaleDynamics of the bulk phases Ωliq and Ωvap.Model: Isothermal Euler equation
%t + div(% v) = 0,(% v)t + div (% v ⊗ v + p(%) I ) = 0,
with a pressure function p that covers liquidand vapour phase.
Van-der-Waals like Pressure p
%︸ ︷︷ ︸vapour
︸ ︷︷ ︸liquid
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 4/21
Cut Cell MethodMicroscale
n
MicroscaleDynamics at the phase boundary.
We assume that it is sufficient to consider1D Riemann type problems normal to Γh._ sharp interface models_ exact (Liu) solver [Jägle, Rohde, Z 2012]_ approximate (KinRel) solver
[Rohde, Z 2013]_ exact (KinRel) Riemannsolver [today]
_ diffuse interface models_ molecular dynamic models
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 5/21
Cut Cell MethodTransfer Operator
n
Macro- to microscale_ initial states for Riemann type
problems
Micro- to macroscale_ fluxes for phase boundary edges
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 6/21
Cut Cell Method
Bulk: Euler equation_ liquid phase_ vapour phase
Phase Boundary:_ Riemann type problem_ sharp/diffuse interface model
Bulk:_ curvature reconstruction_ interface tracking
Reconstruction: Compression:
initial states
mean curvature κ
flux atthe phaseboundary
speed ofthe phaseboundary
The cut cell method with Godunov type two phase flux is conservative.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 7/21
Exact Riemann SolverSharp Interface Model
For each macro time step and any interface segmentthere is a Riemann problem to solve:_ Initial condition (
%, v)(x, 0) : =
{(%l, vl) for x ≤ 0,(%r, vr) for x > 0,
w.l.o.g. %l in the liquid phase, %r in the vapour phase._ x = x · n, v = v · n._ Curvature is fixed._ "Bubble case" with κ > 0
"Droplet case" with κ < 0
Γhx
liquid(%l, vl)
vapour(%r, vr)
0
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 8/21
Exact Riemann SolverSharp Interface Model(
%%v
)t
+(
%v%v2 + p(%)
)x
=(
00
)in R× (0,∞).
Riemann Problem_ Classical entropy solution in the bulk phases._ There exists one phase boundary that satisfies
−σ J%K + J% vK = 0−σ J% vK+J% v2 + p(%)K=(d − 1)γκ.
_ The phase boundary satisfies the kinetic relationqg(%) + 0.5 (v − σ)2
y= −k j.
σ speed of the phase boundary J%K := %vap − %liqj = %(v − σ) mass flux τ = 1/% specific volume
p̃(τ) := p(τ−1) pressure (d − 1)γκ (const.) surface tensiong̃(τ) := g(τ−1) chemical potential ψ Helmholz free energy
Exact solvers are available ([LeFloch et al. (≥ 1991)], [Hantke et a. 2013]. . . , [Jägle, Rohde, Z 2012]), but only for simplified models or kinetic re-lations.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 9/21
Exact Riemann SolverSharp Interface Model
Exact Riemann Solver_ Classical entropy solution in the bulk phases._ There exists one phase boundary that satisfies
−σ J%K + J% vK = 0−σ J% vK+J% v2 + p(%)K=(d − 1)γκ.
_ The phase boundary satisfies the kinetic relationqg(%) + 0.5 (v − σ)2
y= −k j.
Then, for k > 0, follows for the total energy e = ψ + 12 v2:
−σ(J%eK + (d − 1)γκ
)+ J(%e + p) vK = −k j2 ≤ 0
Exact solvers are available ([LeFloch et al. (≥ 1991)], [Hantke et a. 2013]. . . , [Jägle, Rohde, Z 2012]), but only for simplified models or kinetic re-lations.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 9/21
Exact Riemann SolverGibbs-Thomson based Kinetic Relation
Admissible Phase Boundary Wave_ connects liquid state (τliq, vliq) and vapour state (τvap, vvap),_ satisfies
J%(v − σ)K = 0,j JvK + Jp̃(τ)K=(d − 1)γκ
}⇒ j = ±
√(d − 1)γκ− Jp̃(τ)K
JτK
_ and the kinetic relationqg̃(τ) + 0.5 j2 τ2
y= −k j.
σ speed of the phase boundary J%K := %vap − %liqj = %(v − σ) mass flux τ = 1/% specific volume
p̃(τ) := p(τ−1) pressure (d − 1)γκ (const.) surface tensiong̃(τ) := g(τ−1) chemical potential ψ Helmholz free energy
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 10/21
Exact Riemann SolverGibbs-Thomson based Kinetic Relation
Example: Stationary Phase Boundary_ connects liquid state (τmwliq , vmwliq ) and vapour state (τmwvap , vmwvap ),_ satisfies
j = 0,Jp̃(τ)K = (d − 1)γκ
_ and the kinetic relationJg̃(τ)K = 0.
σ speed of the phase boundary J%K := %vap − %liqj = %(v − σ) mass flux τ = 1/% specific volume
p̃(τ) := p(τ−1) pressure (d − 1)γκ (const.) surface tensiong̃(τ) := g(τ−1) chemical potential ψ Helmholz free energy
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 10/21
Exact Riemann Solver
Admissible phase boundaries for k = 1 (without surface tension)
6 8 10 12 14 16 180.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)
0 5 10 15
pressure
volume
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 11/21
Exact Riemann Solver
Admissible phase boundaries for k → 0 (without surface tension)
6 8 10 12 14 16 180.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)
0 5 10 15
pressure
volume
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 11/21
Exact Riemann Solver
Admissible phase boundaries for k = 1 (without surface tension)
6 8 10 12 14 16 180.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)
0 5 10 15
pressure
volume
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 11/21
Exact Riemann Solver
Admissible phase boundaries for k = 2 (without surface tension)
6 8 10 12 14 16 180.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)
0 5 10 15
pressure
volume
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 11/21
Exact Riemann Solver
Admissible phase boundaries for k = 3.5 (without surface tension)
6 8 10 12 14 16 180.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)
0 5 10 15
pressure
volume
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 11/21
Exact Riemann Solver
Admissible phase boundaries for k = 1 with surface tension
6 7 8 9 10 11 12 13 14 15 16 170.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
0 5 10 15
pressure
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)planar
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 11/21
Exact Riemann SolverKinetic Relation based on the Generalized Gibbs-Thomson LawThere ex. kinetic functions fc (condensation), fe (evaporation) such that
fc(τvap) = τliq∨ fe(τliq) = τvap
}⇔
qg̃(τ) + 0.5 j2 τ2
y= −k j.
k = 0 Reversible process fc(fe(τliq)) = τliq.0 ≤ k < k∗ Monotone functions τvap 7→ fc and τliq 7→ fe.
k > k∗ Phase transition in metastable region.Loss of monotonicity → uniqueness?
Monotone Kinetic Functions with Maximal Entropy DissipationDefine f mc (τvap) := τmwliq and f me (τliq) = τmwvap .Observation:_ The Liu entropy criterion applied on a modified pressure based on
the Maxwell equal area rule leads to f mc , f me .
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 12/21
Exact Riemann Solver
Monotone Kinetic Functions with Maximal Entropy Dissipation
6 8 10 12 14 16 18 20 220.4645
0.465
0.4655
0.466
0.4665
0.467
0.4675
0.468
0.4685
volume vapour phase
volu
me
liqui
d ph
ase
complex jcondensation (j < 0)evaporation (j > 0)maxwell states (j = 0)
0 5 10 15
pressure
volume
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 13/21
Exact Riemann Solver
Based on fc and fe we construct the full wave fan. Phase boundaries ofLax type are allowed but undercompresive waves are "preferred".
Theorem [Z 2014]The Riemann problem for |κ| < C and the kinetic relation based on thegeneralized Gibbs-Thomson law with 0 ≤ k < k∗ or has a unique entropysolution. The solution consist of elementary waves and exactly one phaseboundary satisfying
−σ(J%eK + (d − 1)γκ
)+ J(%e + p) vK ≤ 0
for e = ψ + 12 v2.
For the construction, we follow [LeFloch 2002].
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 14/21
Exact Riemann SolverExample
Density of examples with varying surface tension:
−0.2 0 0.2 0.4 0.6 0.8 1 1.20.12
0.13
0.14
0.15−3.5 −3 −2.5 −2 −1.5 −1 −0.5 0 0.5
2.12
2.14
2.16
2.18
κ0
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 15/21
Numerical Results
Benchmark Problem for Surface Tension
Cut cell method for radially symmetric solutionson Ω =
{x ∈ Rd
∣∣ 0 < |x| = r < 1 } with phaseboundary Γ(t) =
{x ∈ Rd
∣∣ |x| = rΓ(t) }. x1x2
rΓ(t)
_ Bulk system:(%% v
)t
+(
% v% v2 + p(%)
)r
= 1−dr
(% v% v2
)for r ∈ (0, rΓ) ∪ (rΓ, 1),t > 0.
_Simple interface tracking (rn+1Γ = rnΓ + ∆t σn)and curvature reconstruction (κn = 1/rnΓ ).
d = 1: Fully conservative [Chalons, Wiebe]d > 1: Mass conservative (multidimensional sence) [Rohde, Z 2013]
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 16/21
Numerical ResultsGlobal Energy (cf. [Gurtin 1985])
E(%, v) =∫
Ω
12% |v|
2 + %ψ(%) dx + γ |Γ| ,
Estat = min{
E(%,0)∣∣ ∫
Ω % dx = const.}
Energy
0 5 10 15−22.95
−22.9
−22.85
−22.8
−22.75
−22.7
−22.65
Time
KinRel k=0Mon.Max.Ent.LiuE
statE
stat planar
(Initial conditions %L = %mwliq , %R = %mwvap, vR = 0.1, vL = −0.1, γ = 0.01, d = 2)
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 17/21
Numerical Results
Experimental order of convergence
Cells Error Order100 1.7e-03200 1.1e-03 0.68500 5.7e-04 0.701000 3.4e-04 0.741500 2.5e-04 0.762000 2.0e-04 0.762500 1.7e-04 0.753000 1.5e-04 0.75
Velocity (zoom)
0 0.1 0.2 0.3 0.4 0.5 0.6
0
0.05
0.1
v
h
v
(Initial conditions %l = 2.1368, %r = 0.0333, v = 0, k = 0.0001, reference solutionfrom exact Riemann solver, d = 1)
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 18/21
Numerical ResultsApplication in 2d (with P. Engel)
Pure Liu Riemannsolver,
%(x, 0) ={0.319 : inside,1.806 : outside,
v(x, 0) = 0,γ = 0.001.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 19/21
Summary_ Conservative front tracking scheme._ Exact Riemann solver
_ based on the generalized Gibbs-Thomson law._ for arbitrary pressure laws
(Peng Robinson, external library (FPROPS [IAPWS])).
OutlookApproximative solver for the full Euler system.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 20/21
Literature[Jägle, Rohde, Z 2012] F. Jaegle, C. Rohde, and C. Zeiler.
A multiscale method for compressible liquid-vapor flow with surface tension.ESAIM: Proc., 38:387–408, 2012.
[Rohde, Z 2013] C. Rohde and C. Zeiler.A relaxation riemann solver for compressible two-phase flow with phase transitionand surface tension.accepted for publication in Applied Numerical Mathematics, 2013.
[Wiebe 2014] M. Wiebe.A sharp-interface approach for phase transition problems.Master’s thesis, Universität Stuttgart, 2014.
[Kabil, Rohde 2013] B. Kabil and C. Rohde.The influence of surface tension and configurational forces on the stability ofliquid-vapor interfaces.
[Hantke et a. 2013] M. Hantke, W. Dreyer, and G. Warnecke.Exact solutions to the riemann problem for compressible isothermal euler equationsfor two-phase flows with and without phase transition.
[LeFloch 2002] P.G. LeFloch.Hyperbolic systems of conservation laws.
Christoph Zeiler Sharp Interface Approach for Liquid-Vapour Flow with Phase Transition 21/21