On implicitly constituted incompressible fluids Josef M´alek

advertisement
On implicitly constituted incompressible fluids
Josef Málek
Mathematical Institute of the Charles University
Sokolovská 83, 186 75 Prague 8, Czech Republic
M. Bulı́ček, P. Gwiazda, J. Málek and A. Swierczewska-Gwiazda
KR Rajagopal
M. Heida, V.Průša
July 6, 2010
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
1 / 54
Formulation of problem
Governing equations
Equations in a bounded domain Ω ⊂ R3 for t ∈ [0, T ]:
div v = 0
v,t + div(v ⊗ v) − div S = −∇p + f
S = ST
• v is the velocity of the fluid
• p is the mean normal stress (pressure) p := − 31 tr T
• f external body forces ( ≡ 0)
• S is the constitutively determined (deviatoric) part of the Cauchy stress
The Cauchy stress: T = −pII + S
Málek (Charles University in Prague)
T = T − 13 (tr T )II + 31 (tr T )II
Implicit fluids & Orlicz spaces
July 6, 2010
2 / 54
Constitutive equations
Point-wisely given constitutive equations
D(v) := ∇v + (∇v)T .
• D (v) - the symmetric part of the velocity gradient: 2D
• Consider merely point-wise relations between D and S (or D and T )
NO integral, differential (rate-type) or stochastic constitutive relations:
S, D ) = 0
G (S
or
G(T
T, D ) = 0
G̃
robust class of fluids
justification to adhoc models
easy incorporation of constraints (as div v = 0)
S) vrs S = H̃
H(D
D)
new class of explicit models D = H (S
Extensions:
S, D , p, x, t, temperature, density, concentration, etc.) = 0
G (S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
3 / 54
Constitutive equations
Point-wisely given constitutive equations
D(v) := ∇v + (∇v)T .
• D (v) - the symmetric part of the velocity gradient: 2D
• Consider merely point-wise relations between D and S (or D and T )
NO integral, differential (rate-type) or stochastic constitutive relations:
S, D ) = 0
G (S
or
G(T
T, D ) = 0
G̃
robust class of fluids
justification to adhoc models
easy incorporation of constraints (as div v = 0)
S) vrs S = H̃
H(D
D)
new class of explicit models D = H (S
Extensions:
S, D , p, x, t, temperature, density, concentration, etc.) = 0
G (S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
3 / 54
Constitutive equations
Navier-Stokes fluids
T = −pII + 2µ∗D ⇐⇒ S = 2µ∗D ⇐⇒ D =
1
S
2µ∗
0 ≤ ξ = S ·D
D|2 = (2µ∗ )−1 |S
S |2
= 2µ∗ |D
1
S |2
D|2 + (2µ∗ )−1 |S
= µ∗ |D
2
µ∗ = 1/2
=⇒ S = D
ξ =S·D =
Málek (Charles University in Prague)
D
S ·D
2
D
D|2 + 21 |S
S |2
+ S2·D
= 12 |D
Implicit fluids & Orlicz spaces
July 6, 2010
4 / 54
Constitutive equations
Navier-Stokes fluids
T = −pII + 2µ∗D ⇐⇒ S = 2µ∗D ⇐⇒ D =
1
S
2µ∗
0 ≤ ξ = S ·D
D|2 = (2µ∗ )−1 |S
S |2
= 2µ∗ |D
1
S |2
D|2 + (2µ∗ )−1 |S
= µ∗ |D
2
µ∗ = 1/2
=⇒ S = D
ξ =S·D =
Málek (Charles University in Prague)
D
S ·D
2
D
D|2 + 21 |S
S |2
+ S2·D
= 12 |D
Implicit fluids & Orlicz spaces
July 6, 2010
4 / 54
Constitutive equations
Navier-Stokes fluids
T = −pII + 2µ∗D ⇐⇒ S = 2µ∗D ⇐⇒ D =
1
S
2µ∗
0 ≤ ξ = S ·D
D|2 = (2µ∗ )−1 |S
S |2
= 2µ∗ |D
1
S |2
D|2 + (2µ∗ )−1 |S
= µ∗ |D
2
µ∗ = 1/2
=⇒ S = D
ξ =S·D =
Málek (Charles University in Prague)
D
S ·D
2
D
D|2 + 21 |S
S |2
+ S2·D
= 12 |D
Implicit fluids & Orlicz spaces
July 6, 2010
4 / 54
Constitutive equations
Power-law fluids
2−r
1
S| r −1 S
D|r −2D ⇐⇒ S = 2µ∗ |D
D|r −2D ⇐⇒ D = [2µ∗ ]− r −1 |S
T = −pII + 2µ∗ |D
µ∗ = 1/2
r ′ := r /(r − 1)
D|r = |S
S|r /(r −1)
ξ = S · D = |D
=
D
S ·D
r
+
D
S ·D
r′
=
D|r
|D
r
+
S|r
|S
r′
′
Also, for all D , E ∈ R3×3
D) − S̃(E
E) · (D
D − E) ≥ 0 ,
S̃(D
where
for all S 1 , S 2 ∈ R3×3
S1 − S 2 ) · B (S
S1 ) − B (S
S2 ) ≥ 0 ,
(S
B) := 2µ∗ |B
B|r −2B
S̃(B
2−r
S) := 2µ∗ |S
S| r −1 S
where B (S
Generalizations
D|2 )r −2D
S = (1 + |D
D|2 )D
D
S = ν(|D
Málek (Charles University in Prague)
2−r
S|2 ) r −1 S
D = (1 + |S
S|2 )S
S
D = µ(|S
Implicit fluids & Orlicz spaces
July 6, 2010
5 / 54
Constitutive equations
Power-law fluids
2−r
1
S| r −1 S
D|r −2D ⇐⇒ S = 2µ∗ |D
D|r −2D ⇐⇒ D = [2µ∗ ]− r −1 |S
T = −pII + 2µ∗ |D
µ∗ = 1/2
r ′ := r /(r − 1)
D|r = |S
S|r /(r −1)
ξ = S · D = |D
=
D
S ·D
r
+
D
S ·D
r′
=
D|r
|D
r
+
S|r
|S
r′
′
Also, for all D , E ∈ R3×3
D) − S̃(E
E) · (D
D − E) ≥ 0 ,
S̃(D
where
for all S 1 , S 2 ∈ R3×3
S1 − S 2 ) · B (S
S1 ) − B (S
S2 ) ≥ 0 ,
(S
B) := 2µ∗ |B
B|r −2B
S̃(B
2−r
S) := 2µ∗ |S
S| r −1 S
where B (S
Generalizations
D|2 )r −2D
S = (1 + |D
D|2 )D
D
S = ν(|D
Málek (Charles University in Prague)
2−r
S|2 ) r −1 S
D = (1 + |S
S|2 )S
S
D = µ(|S
Implicit fluids & Orlicz spaces
July 6, 2010
5 / 54
Constitutive equations
Power-law fluids
2−r
1
S| r −1 S
D|r −2D ⇐⇒ S = 2µ∗ |D
D|r −2D ⇐⇒ D = [2µ∗ ]− r −1 |S
T = −pII + 2µ∗ |D
µ∗ = 1/2
r ′ := r /(r − 1)
D|r = |S
S|r /(r −1)
ξ = S · D = |D
=
D
S ·D
r
+
D
S ·D
r′
=
D|r
|D
r
+
S|r
|S
r′
′
Also, for all D , E ∈ R3×3
D) − S̃(E
E) · (D
D − E) ≥ 0 ,
S̃(D
where
for all S 1 , S 2 ∈ R3×3
S1 − S 2 ) · B (S
S1 ) − B (S
S2 ) ≥ 0 ,
(S
B) := 2µ∗ |B
B|r −2B
S̃(B
2−r
S) := 2µ∗ |S
S| r −1 S
where B (S
Generalizations
D|2 )r −2D
S = (1 + |D
D|2 )D
D
S = ν(|D
Málek (Charles University in Prague)
2−r
S|2 ) r −1 S
D = (1 + |S
S|2 )S
S
D = µ(|S
Implicit fluids & Orlicz spaces
July 6, 2010
5 / 54
Constitutive equations
Power-law fluids
2−r
1
S| r −1 S
D|r −2D ⇐⇒ S = 2µ∗ |D
D|r −2D ⇐⇒ D = [2µ∗ ]− r −1 |S
T = −pII + 2µ∗ |D
µ∗ = 1/2
r ′ := r /(r − 1)
D|r = |S
S|r /(r −1)
ξ = S · D = |D
=
D
S ·D
r
+
D
S ·D
r′
=
D|r
|D
r
+
S|r
|S
r′
′
Also, for all D , E ∈ R3×3
D) − S̃(E
E) · (D
D − E) ≥ 0 ,
S̃(D
where
for all S 1 , S 2 ∈ R3×3
S1 − S 2 ) · B (S
S1 ) − B (S
S2 ) ≥ 0 ,
(S
B) := 2µ∗ |B
B|r −2B
S̃(B
2−r
S) := 2µ∗ |S
S| r −1 S
where B (S
Generalizations
D|2 )r −2D
S = (1 + |D
D|2 )D
D
S = ν(|D
Málek (Charles University in Prague)
2−r
S|2 ) r −1 S
D = (1 + |S
S|2 )S
S
D = µ(|S
Implicit fluids & Orlicz spaces
July 6, 2010
5 / 54
Constitutive equations
Power-law fluids
2−r
1
S| r −1 S
D|r −2D ⇐⇒ S = 2µ∗ |D
D|r −2D ⇐⇒ D = [2µ∗ ]− r −1 |S
T = −pII + 2µ∗ |D
µ∗ = 1/2
r ′ := r /(r − 1)
D|r = |S
S|r /(r −1)
ξ = S · D = |D
=
D
S ·D
r
+
D
S ·D
r′
=
D|r
|D
r
+
S|r
|S
r′
′
Also, for all D , E ∈ R3×3
D) − S̃(E
E) · (D
D − E) ≥ 0 ,
S̃(D
where
for all S 1 , S 2 ∈ R3×3
S1 − S 2 ) · B (S
S1 ) − B (S
S2 ) ≥ 0 ,
(S
B) := 2µ∗ |B
B|r −2B
S̃(B
2−r
S) := 2µ∗ |S
S| r −1 S
where B (S
Generalizations
D|2 )r −2D
S = (1 + |D
D|2 )D
D
S = ν(|D
Málek (Charles University in Prague)
2−r
S|2 ) r −1 S
D = (1 + |S
S|2 )S
S
D = µ(|S
Implicit fluids & Orlicz spaces
July 6, 2010
5 / 54
Constitutive equations
Power-law fluids
2−r
1
S| r −1 S
D|r −2D ⇐⇒ S = 2µ∗ |D
D|r −2D ⇐⇒ D = [2µ∗ ]− r −1 |S
T = −pII + 2µ∗ |D
µ∗ = 1/2
r ′ := r /(r − 1)
D|r = |S
S|r /(r −1)
ξ = S · D = |D
=
D
S ·D
r
+
D
S ·D
r′
=
D|r
|D
r
+
S|r
|S
r′
′
Also, for all D , E ∈ R3×3
D) − S̃(E
E) · (D
D − E) ≥ 0 ,
S̃(D
where
for all S 1 , S 2 ∈ R3×3
S1 − S 2 ) · B (S
S1 ) − B (S
S2 ) ≥ 0 ,
(S
B) := 2µ∗ |B
B|r −2B
S̃(B
2−r
S) := 2µ∗ |S
S| r −1 S
where B (S
Generalizations
D|2 )r −2D
S = (1 + |D
D|2 )D
D
S = ν(|D
Málek (Charles University in Prague)
2−r
S|2 ) r −1 S
D = (1 + |S
S|2 )S
S
D = µ(|S
Implicit fluids & Orlicz spaces
July 6, 2010
5 / 54
Constitutive equations
Fluids with shear-rate dependent viscosities
S := S (D
D))
Continuous Explicit Standard Power-Law models (S
D |2 )
µ(|D
D(v)|2 = 1/2|u ′ |2 := κ shear rate
v = (u(y ), 0, 0) =⇒ |D
D|2 ) = 2µ∗ |D
D|r −2
µ(|D
2
2µ∗0
2
2µ∗0 (ǫ
D| ) =
µ(|D
D| ) =
µ(|D
+
D|r −2
µ∗1 |D
1<r <∞
2 r −2
D| )
+ |D
1<r <∞
1∈R
power-law like fluids =⇒ r -coercivity, (r − 1)-growth and strict monotonicity
fluids with shear-rate dependent viscosity
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
6 / 54
Constitutive equations
Classical power-law model for various power-law index
m ∈ (0, +∞)
shear thickening
m=0
Navier–Stokes
m ∈ − 21 , 0
shear thinning
|Tδ |
m = − 12
limit case
2µ
√0
λ
m ∈ −∞, − 21
nonmonotone
0
0
|D|
D|2 )mD
S = (1 + |D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
7 / 54
Constitutive equations
Stress power-law model for various power-law index
D := D (S
S))
Continuous Explicit Stress Power-law models (D
n ∈ −∞, − 21
n = − 21
n ∈ − 21 , 0
n=0
|Tδ |
n ∈ (0, +∞)
0
0
√α
β
|D|
S|2 )nS
D = (1 + |S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
8 / 54
Constitutive equations
Power-law like fluids with activation criteria/discontinuous
stresses
threshold value for the stress to
start flow
Bingham fluid
Herschel-Bingham fluid
S
drastic changes of the properties
when certain criterion is met
111111111111111111111111111
000000000000000000000000000
K=|u’(r)|
Málek (Charles University in Prague)
formation and dissolution of
blood
chemical reactions/time scale
Implicit fluids & Orlicz spaces
July 6, 2010
9 / 54
Constitutive equations
Power-law like fluids with activation criteria/II
S| > τ ∗
|S
if and only if
S = τ∗
S| ≤ τ ∗
|S
if and only if
D=0
D
D|2 )D
D
+ 2µi (|D
D|
|D
is equivalent to
Similarly:
+
D|2 ) τ ∗ + (|S
S| − τ ∗ )+ D = |S
S| − τ ∗ S
2µi (|D
D|2 )D
D
S = µα (|D
D|2 )D
D
S = µβ (|D
∗
S=µ D
if
if
if
D| < d ∗
|D
D| > d ∗
|D
D| = d ∗ ,
|D
∗
∗ µα (s) and µ
∗ µβ (s)
µ∗ takes any value between µ∗α := lims→d−
β := lims→d+
D| − d ∗ |S
S = M(|D
D|2 )(|D
D| − d ∗ )D
D
| |D
with M(s) := max{µα (s)sgn(s − d ∗ ); µβ (s)sgn(s − d ∗ )}
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
10 / 54
Constitutive equations
Power-law like fluids with activation criteria/II
S| > τ ∗
|S
if and only if
S = τ∗
S| ≤ τ ∗
|S
if and only if
D=0
D
D|2 )D
D
+ 2µi (|D
D|
|D
is equivalent to
Similarly:
+
D|2 ) τ ∗ + (|S
S| − τ ∗ )+ D = |S
S| − τ ∗ S
2µi (|D
D|2 )D
D
S = µα (|D
D|2 )D
D
S = µβ (|D
∗
S=µ D
if
if
if
D| < d ∗
|D
D| > d ∗
|D
D| = d ∗ ,
|D
∗
∗ µα (s) and µ
∗ µβ (s)
µ∗ takes any value between µ∗α := lims→d−
β := lims→d+
D| − d ∗ |S
S = M(|D
D|2 )(|D
D| − d ∗ )D
D
| |D
with M(s) := max{µα (s)sgn(s − d ∗ ); µβ (s)sgn(s − d ∗ )}
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
10 / 54
Constitutive equations
Power-law like fluids with activation criteria/II
S| > τ ∗
|S
if and only if
S = τ∗
S| ≤ τ ∗
|S
if and only if
D=0
D
D|2 )D
D
+ 2µi (|D
D|
|D
is equivalent to
Similarly:
+
D|2 ) τ ∗ + (|S
S| − τ ∗ )+ D = |S
S| − τ ∗ S
2µi (|D
D|2 )D
D
S = µα (|D
D|2 )D
D
S = µβ (|D
∗
S=µ D
if
if
if
D| < d ∗
|D
D| > d ∗
|D
D| = d ∗ ,
|D
∗
∗ µα (s) and µ
∗ µβ (s)
µ∗ takes any value between µ∗α := lims→d−
β := lims→d+
D| − d ∗ |S
S = M(|D
D|2 )(|D
D| − d ∗ )D
D
| |D
with M(s) := max{µα (s)sgn(s − d ∗ ); µβ (s)sgn(s − d ∗ )}
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
10 / 54
Constitutive equations
Power-law like fluids with activation criteria/II
S| > τ ∗
|S
if and only if
S = τ∗
S| ≤ τ ∗
|S
if and only if
D=0
D
D|2 )D
D
+ 2µi (|D
D|
|D
is equivalent to
Similarly:
+
D|2 ) τ ∗ + (|S
S| − τ ∗ )+ D = |S
S| − τ ∗ S
2µi (|D
D|2 )D
D
S = µα (|D
D|2 )D
D
S = µβ (|D
∗
S=µ D
if
if
if
D| < d ∗
|D
D| > d ∗
|D
D| = d ∗ ,
|D
∗
∗ µα (s) and µ
∗ µβ (s)
µ∗ takes any value between µ∗α := lims→d−
β := lims→d+
D| − d ∗ |S
S = M(|D
D|2 )(|D
D| − d ∗ )D
D
| |D
with M(s) := max{µα (s)sgn(s − d ∗ ); µβ (s)sgn(s − d ∗ )}
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
10 / 54
Constitutive equations
Discontinuous response described by a maximal monotone graph
T12
Tmax
shear rate
T1
T2
Málek (Charles University in Prague)
shear rate
T
Implicit fluids & Orlicz spaces
July 6, 2010
11 / 54
Constitutive equations
Perfect plasticity
Ugly “discontinuous” explicit models such as
Perfect plasticity
D| = 0 =⇒ |S
S| ≤ 1
|D
D| > 0 =⇒ S :=
|D
D
D|
|D
can be described by a nice continuous implicit formula
D|S
S − D | + (|S
S| − 1)+ = 0
||D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
12 / 54
Constitutive equations
Implicit theories/I - KR Rajagopal since 2003
Implicit constitutive theory: ability to capture responses of larger set of materials
T, D ) = 0
G (T
Isotropy of the material implies
TD + DT )
α0I + α1T + α2D + α3T 2 + α4D 2 + α5 (T
T2D + DT 2 ) + α7 (T
TD 2 + D 2T ) + α8 (T
T 2D 2 + D 2T 2 ) = 0
+ α6 (T
αi being a functions of
TD ), tr(T
T2D ), tr(D
D2T ), tr(D
D 2T 2 )
tr T , tr D , tr T 2 , tr D 2 , tr T 3 , tr D 3 , tr(T
For incompressible fluids
T=
Málek (Charles University in Prague)
tr T
3
D
I + µ(tr T , tr D 2 )D
Implicit fluids & Orlicz spaces
July 6, 2010
13 / 54
Constitutive equations
Implicit theories/II
Implicit constitutive theory: ability to include constraints in an easy way
If
D)
T = G 1 (D
isotropy of the material implies
T = β0 I + β1 D + β2 D 2
βi = βi (tr D 2 , tr D 3 )
If
T)
D = G 2 (T
isotropy of the material leads to
D = γ 0 I + γ1 T + γ 2 T 2
T2 −
= γ1S + γ2 (T
Málek (Charles University in Prague)
γi = γi (tr T , tr T 2 , tr T 3 )
tr T 2
I)
3
Implicit fluids & Orlicz spaces
July 6, 2010
14 / 54
Constitutive equations
Implicit theories/II
Implicit constitutive theory: ability to include constraints in an easy way
If
D)
T = G 1 (D
isotropy of the material implies
T = β0 I + β1 D + β2 D 2
βi = βi (tr D 2 , tr D 3 )
If
T)
D = G 2 (T
isotropy of the material leads to
D = γ 0 I + γ1 T + γ 2 T 2
T2 −
= γ1S + γ2 (T
Málek (Charles University in Prague)
γi = γi (tr T , tr T 2 , tr T 3 )
tr T 2
I)
3
Implicit fluids & Orlicz spaces
July 6, 2010
14 / 54
Constitutive equations
Implicit formulation - maximal monotone ψ-graph setting
S, D ) ∈ A
D, S ) = 0
(S
⇐⇒
G (D
Assumptions (A is a ψ-maximal monotone graph):
(A1)
(A2)
(0, 0) ∈ A
S1 , D 1 ), (S
S2 , D 2 ) ∈ A
Monotone graph: For any (S
S1 − S 2 ) : (D
D1 − D 2 ) ≥ 0
(S
No strict monotonicity is needed!
(A3)
S, D ) there holds
Maximal graph: If for some (S
S − S̃
S) : (D
D − D̃
D) ≥ 0
(S
S, D̃
D) ∈ A
∀ (S̃
then
S, D ) ∈ A
(S
(A4)
S, D ) ∈ A
ψ-graph: There are α ∈ (0, 1] and g > 0 so that for any (S
D) + ψ ∗ (S
S)) − g
S : D ≥ α(ψ(D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
15 / 54
Constitutive equations
What is ψ? An excursion to Orlicz spaces
Assume that ψ : R3×3
sym → R is an N - function (if it depends only on the modulus then
Young function), i.e.,
ψ is convex and continuous
D) = ψ(−D
D)
ψ(D
lim
D|→0+
|D
D)
ψ(D
= 0,
D|
|D
lim
D|→∞
|D
D)
ψ(D
=∞
D|
|D
We define the conjugate function ψ∗:
S) := max (S
S · D − ψ(D
D))
ψ ∗ (S
D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
16 / 54
Constitutive equations
What is ψ? An excursion to Orlicz spaces
Assume that ψ : R3×3
sym → R is an N - function (if it depends only on the modulus then
Young function), i.e.,
ψ is convex and continuous
D) = ψ(−D
D)
ψ(D
lim
D|→0+
|D
D)
ψ(D
= 0,
D|
|D
lim
D|→∞
|D
D)
ψ(D
=∞
D|
|D
We define the conjugate function ψ∗:
S) := max (S
S · D − ψ(D
D))
ψ ∗ (S
D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
16 / 54
Constitutive equations
What is ψ? An excursion to Orlicz spaces/2
• Young inequality:
D) + ψ ∗ (S
S)
S : D ≤ ψ(D
• Orlicz spaces: The Orlicz space Lψ (Ω)d×d is the set of all measurable function
D : Ω → R3×3
sym such that
ˆ
ψ(λ−1D ) dx = 0
lim
λ→∞
Ω
with the norm
DkLψ := inf{λ;
kD
• Hölder inequality
ˆ
Ω
• ∆2 -condition
Málek (Charles University in Prague)
ˆ
Ω
ψ(λ−1D ) dx ≤ 1}
ab dx ≤ 2kakLψ (Ω) kbkLψ∗ (Ω)
D) ≤ C1 ψ(D
D) + C2
ψ(2D
Implicit fluids & Orlicz spaces
July 6, 2010
17 / 54
Constitutive equations
Maximization of entropy production
In order to specify the constitutive relations, the principle of maximal entropy production
(laziness, economy) is used (KR Rajagopal, A Srinivasa):
S ·D = ξ ≥ 0
(*)
D) ≥ 0 and for some fixed S we would like to maximize ξ
Let us assume that ξ := ξ(D
with the constraint (*).
D |2
ξ := 2ν0 |D
D|)|D
D|
ξ = ν(|D
S = 2ν0D
2
Málek (Charles University in Prague)
D|)D
D
S = ν(|D
Implicit fluids & Orlicz spaces
July 6, 2010
18 / 54
Constitutive equations
Maximization of entropy production - dual view
S) ≥ 0 and for some fixed D we would like to maximize ξ
Let us assume that ξ := ξ(S
with the constraint ξ = S · D .
ξ :=
2
S |2
|S
ν0
∗
S|)|S
S|
ξ = ν (|S
D = 2ν0S
2
Málek (Charles University in Prague)
S|)S
S
D = ν ∗ (|S
Implicit fluids & Orlicz spaces
July 6, 2010
19 / 54
Constitutive equations
Maximization of entropy production
D, S) ≥ 0 and
Let us assume that ξ := ξ(D
(i) for some fixed S we would like to maximize ξ with the constraint ξ = S · D
or
(ii) for some fixed D we would like to maximize ξ with the constraint ξ = S · D
ξ :=
ξ=
D|2 +|S
S|2
|D
2
D|r
|D
r
+
′
S|r
|S
r′
Málek (Charles University in Prague)
S=D
D|r −1D
S = |D
Implicit fluids & Orlicz spaces
July 6, 2010
20 / 54
Constitutive equations
Optimality of ψ and ψ ∗
D) + ξ2 (S
S) ≥ 0 - not necessarily conjugate and
Let us assume that ξ := ξ1 (D
(i) for some fixed S we would like to maximize ξ with the constraint ξ = S · D
or
(ii) for some fixed D we would like to maximize ξ with the constraint ξ = S · D
It is the same as maximize ξ1 with the constraint
S) = ξ1 (D
D)
S · D − ξ2 (S
Hence, for D - the point where maximum is reached - we interchange the role of S and
D , so at this point
S · D − ξ2 (S
S)) = ξ1 (D
D)
max (S
S
But it implies
D) := max (S
S · D − ξ2 (S
S)) = ξ1 (D
D)
ξ2∗ (D
S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
21 / 54
Constitutive equations
Optimality of ψ and ψ ∗
D) + ξ2 (S
S) ≥ 0 - not necessarily conjugate and
Let us assume that ξ := ξ1 (D
(i) for some fixed S we would like to maximize ξ with the constraint ξ = S · D
or
(ii) for some fixed D we would like to maximize ξ with the constraint ξ = S · D
It is the same as maximize ξ1 with the constraint
S) = ξ1 (D
D)
S · D − ξ2 (S
Hence, for D - the point where maximum is reached - we interchange the role of S and
D , so at this point
S · D − ξ2 (S
S)) = ξ1 (D
D)
max (S
S
But it implies
D) := max (S
S · D − ξ2 (S
S)) = ξ1 (D
D)
ξ2∗ (D
S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
21 / 54
Constitutive equations
Optimality of ψ and ψ ∗
D) + ξ2 (S
S) ≥ 0 - not necessarily conjugate and
Let us assume that ξ := ξ1 (D
(i) for some fixed S we would like to maximize ξ with the constraint ξ = S · D
or
(ii) for some fixed D we would like to maximize ξ with the constraint ξ = S · D
It is the same as maximize ξ1 with the constraint
S) = ξ1 (D
D)
S · D − ξ2 (S
Hence, for D - the point where maximum is reached - we interchange the role of S and
D , so at this point
S · D − ξ2 (S
S)) = ξ1 (D
D)
max (S
S
But it implies
D) := max (S
S · D − ξ2 (S
S)) = ξ1 (D
D)
ξ2∗ (D
S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
21 / 54
Constitutive equations
Optimality of ψ and ψ ∗
D) + ξ2 (S
S) ≥ 0 - not necessarily conjugate and
Let us assume that ξ := ξ1 (D
(i) for some fixed S we would like to maximize ξ with the constraint ξ = S · D
or
(ii) for some fixed D we would like to maximize ξ with the constraint ξ = S · D
It is the same as maximize ξ1 with the constraint
S) = ξ1 (D
D)
S · D − ξ2 (S
Hence, for D - the point where maximum is reached - we interchange the role of S and
D , so at this point
S · D − ξ2 (S
S)) = ξ1 (D
D)
max (S
S
But it implies
D) := max (S
S · D − ξ2 (S
S)) = ξ1 (D
D)
ξ2∗ (D
S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
21 / 54
Constitutive equations
Optimality of ψ and ψ ∗ - more general models
Non-polynomial growth
S ∼ (1 + |D
D |2 )
r −2
2
D|)D
D =⇒ ψ(D
D) ∼ |D
D|r ln(1 + |D
D|)
ln(1 + |D
Anisotropic case - different growth
D|rij −2D =⇒ ψ(D
D) ∼
S ij ∼ |D
X
D|rij
|D
Different upper and lower growth in principle - ψ has different polynomial upper
D) := ψ(|D
D|): for certain 1 < r ≤ q < ∞ there are
and lower growth, for ψ(D
positive constants c1 , c2 , c3 and c4 so that
c1 s r − c2 ≤ ψ(s) ≤ c3 s q + c4
=⇒
′
′
c1∗ s q − c2∗ ≤ ψ ∗ (s) ≤ c3∗ s r + c4∗
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
22 / 54
Constitutive equations
Optimality of ψ and ψ ∗ - more general models
Non-polynomial growth
S ∼ (1 + |D
D |2 )
r −2
2
D|)D
D =⇒ ψ(D
D) ∼ |D
D|r ln(1 + |D
D|)
ln(1 + |D
Anisotropic case - different growth
D|rij −2D =⇒ ψ(D
D) ∼
S ij ∼ |D
X
D|rij
|D
Different upper and lower growth in principle - ψ has different polynomial upper
D) := ψ(|D
D|): for certain 1 < r ≤ q < ∞ there are
and lower growth, for ψ(D
positive constants c1 , c2 , c3 and c4 so that
c1 s r − c2 ≤ ψ(s) ≤ c3 s q + c4
=⇒
′
′
c1∗ s q − c2∗ ≤ ψ ∗ (s) ≤ c3∗ s r + c4∗
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
22 / 54
Constitutive equations
Optimality of ψ and ψ ∗ - more general models
Non-polynomial growth
S ∼ (1 + |D
D |2 )
r −2
2
D|)D
D =⇒ ψ(D
D) ∼ |D
D|r ln(1 + |D
D|)
ln(1 + |D
Anisotropic case - different growth
D|rij −2D =⇒ ψ(D
D) ∼
S ij ∼ |D
X
D|rij
|D
Different upper and lower growth in principle - ψ has different polynomial upper
D) := ψ(|D
D|): for certain 1 < r ≤ q < ∞ there are
and lower growth, for ψ(D
positive constants c1 , c2 , c3 and c4 so that
c1 s r − c2 ≤ ψ(s) ≤ c3 s q + c4
=⇒
′
′
c1∗ s q − c2∗ ≤ ψ ∗ (s) ≤ c3∗ s r + c4∗
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
22 / 54
Constitutive equations
Optimality of ψ and ψ ∗ - more general models
Non-polynomial growth
S ∼ (1 + |D
D |2 )
r −2
2
D|)D
D =⇒ ψ(D
D) ∼ |D
D|r ln(1 + |D
D|)
ln(1 + |D
Anisotropic case - different growth
D|rij −2D =⇒ ψ(D
D) ∼
S ij ∼ |D
X
D|rij
|D
Different upper and lower growth in principle - ψ has different polynomial upper
D) := ψ(|D
D|): for certain 1 < r ≤ q < ∞ there are
and lower growth, for ψ(D
positive constants c1 , c2 , c3 and c4 so that
c1 s r − c2 ≤ ψ(s) ≤ c3 s q + c4
=⇒
′
′
c1∗ s q − c2∗ ≤ ψ ∗ (s) ≤ c3∗ s r + c4∗
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
22 / 54
Constitutive equations
What is the goal?
• Goal = existence result for as general constitutive relationships as possible
• Using large data apriori estimates (Ω bounded and nice, nice b.c.)
Steady case
ˆ
Ω
D) + ψ ∗ (S
S) dx ≤ C
ψ(D
Unsteady case
sup kvk22 +
t
ˆ
0
T
ˆ
Ω
D) + ψ ∗ (S
S) dx dt ≤ C
ψ(D
• If the function spaces that are under control are “slightly better” than just to
guarantee that all terms in weak formulation are meaningful, does there exist a weak
solution?
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
23 / 54
Constitutive equations
What is the goal?
• Goal = existence result for as general constitutive relationships as possible
• Using large data apriori estimates (Ω bounded and nice, nice b.c.)
Steady case
ˆ
Ω
D) + ψ ∗ (S
S) dx ≤ C
ψ(D
Unsteady case
sup kvk22 +
t
ˆ
0
T
ˆ
Ω
D) + ψ ∗ (S
S) dx dt ≤ C
ψ(D
• If the function spaces that are under control are “slightly better” than just to
guarantee that all terms in weak formulation are meaningful, does there exist a weak
solution?
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
23 / 54
Constitutive equations
The goal more precisely
If the function spaces generated by the apriori large data energy estimates are
compactly embedded into L2 , does there exist a weak solution?
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
24 / 54
Constitutive equations
Results - power-law like fluid - Explicit
Compact embedding is available if r >
Lebesgue and Sobolev spaces
6
5
r = 2 Lerray (1934)
r≥
r≥
r≥
11
for unsteady, r ≥ 95 steady; Ladyzhenskaya, JL Lions 60’s
5
9
unsteady; Bellout, Bloom, Nečas, Málek, Růžička 90’s
5
8
unsteady; Frehse, Málek, Steinhauer (2000)
5
6
steady; Frehse, Málek, Steinhauer (2003) Diening, Málek,
5
r>
(2008)
r>
6
5
Steinhauer
unsteady; Diening, Růžička, Wolf (2009)
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
25 / 54
Constitutive equations
Results - power-law like fluid - implicit (discontinuous)
Lebesgue and Sobolev spaces
r≥
r>
11
- strictly monotone operators - Gwiazda, Málek, S̀wierczewska
5
9
Herschel-Bulkley model - Málek, Růžička, Shelukhin(2005)
5
6
steady - strictly monotone graph - Bulı́ček, Gwiazda, Málek,
5
(2007)
r>
S̀wierczewska (2009)
r>
6
5
unsteady; Bulı́ček, Gwiazda, Málek, S̀wierczewska-Gwiazda (2010)
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
26 / 54
Constitutive equations
Answers - implicit
Orlicz and Orlicz-Sobolev spaces
subcritical - Gwiazda, S̀wierczevska-Gwiazda et al (2009)
strict monotone operators
the energy equality holds
the term (v ⊗ v) · D (v) ∈ L1 - the solution is an admissible test
function in the weak formulation
supercritical - Bulı́ček, Gwiazda, Málek, S̀wierczewska-Gwiazda (2010)
(A1)-(A4) - maximal monotone ψ-graph
D) = ψ(|D
D|);
ψ(D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
27 / 54
Constitutive equations
Methods
subcritical case
energy equality - v is an addmissible test function
Minty’s method
difficulties if ψ does not satisfy ∆2 condition
supercritical case
generalized Minty’s method
Lipschitz approximation in Orlicz-Sobolev spaces
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
28 / 54
Constitutive equations
Methods
subcritical case
energy equality - v is an addmissible test function
Minty’s method
difficulties if ψ does not satisfy ∆2 condition
supercritical case
generalized Minty’s method
Lipschitz approximation in Orlicz-Sobolev spaces
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
28 / 54
Constitutive equations
Generalized Minty’s method - Convergence lemma
Assume that
A is a maximal monotone ψ-graph satisfying (A1)–(A4)
′
Sn }∞
Dn }∞
{S
n=1 and {D
n=1 satisfy for some Q ⊂ Q
for a.a. (t, x) ∈ Q ′ ,
Sn , D n ) ∈ A
(S
weakly in Lψ (Q ′ ),
Dn ⇀ D
lim sup
n→∞
ˆ
Q′
Sn ⇀ S
ˆ
S n · D n dx dt ≤
S · D dx dt.
∗
weakly in Lψ (Q ′ ),
Q′
Then for almost all (t, x) ∈ Q ′ we have
S, D ) ∈ A
(S
Lemma - Local version
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
29 / 54
Constitutive equations
Application of Convergence lemma to Stokes-like problems
To find (v, p, S ) such that
v ∈ W01,r (Ω)
div v = 0
′
p ∈ Lr (Ω)
D ∈ Lψ (Ω)
− div S = −∇p + f in D′ (Ω),
∗
S ∈ Lψ (Ω)
S(x), D (v(x))) ∈ A for a.a. x ∈ Ω
(S
Theorem. For any f ∈ W01,r
∗
and Ω there is a weak solution to the Problem P.
Proof is based on the following steps:
D take one S ∗ := SD∗ so that (S
S∗ , D ) ∈ A) and its
Take any selection (∀D
η-regularizations leads to η-approximations Pη
Galerkin N-approximations of Pη give finitedimensional problems PN,η
For fix N ∈ N : letting η → 0 we obtain PN
Uniform estimates follow from (A4); Letting N → ∞ and applying Convergence
S, D ) ∈ A a.e. in Ω
lemma one concludes (S
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
30 / 54
Constitutive equations
Extension to subcritical problems
If
compactness in L2 is available (which follows if r >
for unsteady problems)
r > 11
5
9
5
for steady problems and
v is an admissible test function in the weak formulation of the problem
Then the results holds for
div(v ⊗ v) − div S = −∇p + f in Ω
v,t + div(v ⊗ v) − div S = −∇p + f in (0, T ) × Ω and v(0, ·) = v0 ∈ L2div
Supercritical problems: vn − v is not admissible test function =⇒ need for its
appropriate truncation
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
31 / 54
Constitutive equations
Lipschitz approximations of Sobolev function/1
Calderon, Ziemer, Acerbi and Fusco, ...
Theorem. (Diening, Málek, Steinhauer ’08, Frehse, Málek, Steinhauer ’03)
Let 1 < q < ∞ and Ω ∈ C 0,1 . Let
un ∈ W01,q (Ω)d
and un ⇀ 0 weakly in W01,q (Ω)d .
Set
K := sup kun k1,q < ∞,
n
γn := kun kq → 0
√
Let θn > 0 be such that (e.g. θn := γn )
θn → 0
and
(n → ∞).
γn
→0
θn
(n → ∞).
j
Let µj := 22 .
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
32 / 54
Constitutive equations
Lipschitz approximations of Sobolev function/2
Then there exists a sequence λn,j > 0 with
µj ≤ λn,j ≤ µj+1 ,
and a sequence un,j ∈ W01,∞ (Ω)d such that for all j, n ∈ N
kun,j k∞ ≤ θn → 0
n,j
(n → ∞),
k∇u k∞ ≤ c λn,j ≤ c µj+1
and
{un,j 6= un } ⊂ Ω ∩ {Mun > θn } ∪ {M(∇un ) > 2 λn,j } ,
and for all j ∈ N and n → ∞
un,j → 0
un,j ⇀ 0
∗
∇un,j ⇀ 0
Málek (Charles University in Prague)
strongly in Ls (Ω)d for all s ∈ [1, ∞],
weakly in W01,s (Ω)d for all s ∈ [1, ∞),
weakly- ∗ in L∞ (Ω)d×d .
Implicit fluids & Orlicz spaces
July 6, 2010
33 / 54
Constitutive equations
Lipschitz approximations of Sobolev function/3
Furthermore, for all n, j ∈ N
|{un,j 6= un }|d ≤
ckun kq1,q
+c
λqn,j
γn
θn
q
and
k∇un,j χ{un,j 6=un } kq ≤ c kλn,j χ{un,j 6=un } kq ≤ c
γn
µj+1 + c ǫj ,
θn
where ǫj := K 2−j/q vanishes as j → ∞. The constant c depends on Ω.
• based on the continuity of the Hardy-Littlewood maximal function in Lp - In Orlicz
space setting it requires ∆2 -condition and log -continuity w.r.t. x or (t, x)
• Goal is to avoid using continuity of Hardy-Littelwood maximal function; apply weak
(1, 1)-estimates
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
34 / 54
Constitutive equations
Lipschitz approximations of ”Orlicz-Sobolev” functions
Lemma
1
Sn }∞
{un }∞
n=1 such that
n=1 tends strongly to 0 in L and {S
ˆ
Sn |) + ψ(|∇un |) dx ≤ C ∗ (C ∗ > 1).
ψ ∗ (|S
Ω
∗
Then for arbitrary λ ∈ R+ and k ∈ N there exists λmax < ∞ and there exists sequence
n
k
n
n
of {λkn }∞
n=1 and the sequence uk (going to zero) and open sets En := {uk 6= u } such
that λkn ∈ [λ∗ , λmax ] and for any sequence αkn
unk ∈ W 1,p ,
D(unk )k∞ ≤ C λkn ,
kD
C∗
,
ψ(λkn )
k
αnk ψ(λkn /αnk )
αn
n
n
∗
S · D (uk )| dx ≤ CC
|S
+
k
ψ(λkn )
|Ω ∩ Enk | ≤ C
ˆ
Ω∩Enk
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
35 / 54
Constitutive equations
Application of Lipschitz approximations to steady flows
• We have suitable approximations (vn , S n ) and their weak limits (v, S ), we need to show
S, D (v)) ∈ A
that (S
• Test the approximative n- problem by Lipschitz approximation of vn − v, i.e.,
unk := (vn − v)k
S, D ) ∈ A
• One gets (here S is such that (S
k
ˆ
αk ψ(λkn /αnk )
αn
Sn − S ) : D (unk ) ≤ CC ∗
(S
lim
+ n
n→∞ un =un
k
ψ(λkn )
k
• Hölder inequality gives
ˆ
ˆ
Sn − S ) · D (vn − v)|ε ≤
|(S
lim
n→∞
Ω
Málek (Charles University in Prague)
un =unk
+
ˆ
un 6=unk
Implicit fluids & Orlicz spaces
≤ small terms → 0
July 6, 2010
36 / 54
Constitutive equations
Application of Lipschitz approximations to steady flows
• We have suitable approximations (vn , S n ) and their weak limits (v, S ), we need to show
S, D (v)) ∈ A
that (S
• Test the approximative n- problem by Lipschitz approximation of vn − v, i.e.,
unk := (vn − v)k
S, D ) ∈ A
• One gets (here S is such that (S
k
ˆ
αk ψ(λkn /αnk )
αn
Sn − S ) : D (unk ) ≤ CC ∗
(S
lim
+ n
n→∞ un =un
k
ψ(λkn )
k
• Hölder inequality gives
ˆ
ˆ
Sn − S ) · D (vn − v)|ε ≤
|(S
lim
n→∞
Ω
Málek (Charles University in Prague)
un =unk
+
ˆ
un 6=unk
Implicit fluids & Orlicz spaces
≤ small terms → 0
July 6, 2010
36 / 54
Constitutive equations
Application of Lipschitz approximations to steady flows
• We have suitable approximations (vn , S n ) and their weak limits (v, S ), we need to show
S, D (v)) ∈ A
that (S
• Test the approximative n- problem by Lipschitz approximation of vn − v, i.e.,
unk := (vn − v)k
S, D ) ∈ A
• One gets (here S is such that (S
k
ˆ
αk ψ(λkn /αnk )
αn
Sn − S ) : D (unk ) ≤ CC ∗
(S
lim
+ n
n→∞ un =un
k
ψ(λkn )
k
• Hölder inequality gives
ˆ
ˆ
Sn − S ) · D (vn − v)|ε ≤
|(S
lim
n→∞
Ω
Málek (Charles University in Prague)
un =unk
+
ˆ
un 6=unk
Implicit fluids & Orlicz spaces
≤ small terms → 0
July 6, 2010
36 / 54
Constitutive equations
Application of Generalized Minty’s method/Convergence
lemma
Sn − S ) · D (vn − v) to 0; if the strictly monotone
point-wise convergence of (S
property available the proof is finished
if only monotone property is available: apply bf biting lemma; Since
Sn − S ) · D (vn − v) is bounded in L1 there is sequence of non-increasing sets
(S
Ak+1 ⊂ Ak , limk→∞ |Ak | = 0 such that
Sn − S ) · D (vn − v) converges to 0 weakly in L1 (Ω \ Ak )
(S
nonnegativity & point-wise & weak implies strong in L1 (Ω \ Ak )
strong & weak implies for any bounded ϕ
ˆ
ˆ
S n · D (vn )ϕ =
lim
n→∞
Ω\Ak
Ω\Ak
S · D (v)ϕ
apply Convergence lemma
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
37 / 54
Constitutive equations
Application of Generalized Minty’s method/Convergence
lemma
Sn − S ) · D (vn − v) to 0; if the strictly monotone
point-wise convergence of (S
property available the proof is finished
if only monotone property is available: apply bf biting lemma; Since
Sn − S ) · D (vn − v) is bounded in L1 there is sequence of non-increasing sets
(S
Ak+1 ⊂ Ak , limk→∞ |Ak | = 0 such that
Sn − S ) · D (vn − v) converges to 0 weakly in L1 (Ω \ Ak )
(S
nonnegativity & point-wise & weak implies strong in L1 (Ω \ Ak )
strong & weak implies for any bounded ϕ
ˆ
ˆ
S n · D (vn )ϕ =
lim
n→∞
Ω\Ak
Ω\Ak
S · D (v)ϕ
apply Convergence lemma
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
37 / 54
Constitutive equations
Concluding Remarks
Extension of (homogeneous, incompressible) fluids of power-law type to fully
implicit constitutive theory characterized by maximal monotone ψ-graphs (not
necessarilly of power-law type)
Thermodynamically consistent
Ability to capture shear thinning/thickening, activation criteria,
pressure thickening
”Complete” large data existence theory both for steady and unsteady flows
From explicit to implicit, from (v, p) formulation to (v, p, S ) setting
D|) to ψ(D
D)
Extension 1: from ψ(|D
Extension 2: unsteady flows, full thermodynamic setting
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
38 / 54
Constitutive equations
1
2
3
4
5
6
J. Frehse, J. Málek and M. Steinhauer: On analysis of steady flows of fluids with
shear-dependent viscosity based on the Lipschitz truncation method, SIAM J.
Math. Anal. 34, 1064-1083, 2003
L. Diening, J. Málek and M. Steinhauer: On Lipschitz truncations of Sobolev
functions (with variable exponent) and their selected applications, ESAIM:
Control, Optimisation & Calc. Var., 14, 211-232,2008
J. Málek, M. Růžička and V.V. Shelukhin: Herschel-Bulkley Fluids: Existence
and regularity of steady flows, Mathematical Models and Methods in Applied
Sciences, 15, 1845–1861, 2005
P. Gwiazda, J. Málek and A. Świerczewska: On flows of an incompressible fluid
with a discontinuous power-law-like rheology, Computers & Mathematics with
Applications, 53, 531–546, 2007
M. Bulı́ček, P. Gwiazda, J. Málek and A. Świerczewska-Gwiazda: On steady
flows of an incompressible fluids with implicit power-law-like theology, Advances in
Calculus of Variations, 2, 109–136 2009
M. Bulı́ček, P. Gwiazda, J. Málek and A. Świerczewska-Gwiazda: On unsteady
flows of implicitly contituted incompressible fluids, to appear in the Preprint series
of the Nečas Center, 2010
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
39 / 54
Newtonian incompressible heat-conducting fluids
Newtonian and Fourier fluids
Newtonian homogeneous incompressible fluid
D(v)
S = 2ν(e)D
D(v)
or T = −pII + 2ν(e)D
Fourier fluid
q = −κ(e)∇e
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
40 / 54
Newtonian incompressible heat-conducting fluids
”Equivalent” formulation of the balance of energy/1
div v = 0
v,t + div(v ⊗ v) − div S = −∇p
Sv)
(e + |v|2 /2),t + div((e + |v|2 /2 + p)v) + div q = div (S
is equivalent (if v is admissible test function in BM) to
div v = 0
v,t + div(v ⊗ v) − div S = −∇p
e,t + div(ev) + div q = S · D (v)
Helmholtz decomposition u = udiv + ∇g v
Leray’s projector P : u 7→ udiv
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
41 / 54
Newtonian incompressible heat-conducting fluids
”Equivalent” formulation of the balance of energy/2
div v = 0
v,t + div(v ⊗ v) − div S = −∇p
Sv)
(e + |v|2 /2),t + div((e + |v|2 /2 + p)v) + div q = div (S
is equivalent (if v is admissible test function in BM) to
div v = 0
v,t + P div(v ⊗ v) − P div S = 0
e,t + div(ev) + div q = S · D (v)
Advantages/Disadvantages
+ pressure is not included into the 2nd formulation
+ minimum principle for e if S · D (v) ≥ 0
− S · D(v) ∈ L1 while Sv ∈ Lq with q > 1, 2nd form is derived form of BE
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
42 / 54
Newtonian incompressible heat-conducting fluids
D(v) and q = −κ(e)∇e Newtonian case - S = ν(e)D
bounded ν, κ
Theorem 1. (M. Bulı́ček, E. Feireisl, J. Málek ’06 and ’08) Assume that
ν ∗ ≥ ν(s) ≥ ν∗ > 0 and κ∗ ≥ κ(s) ≥ κ∗ > 0
∂Ω ∈ C 1,1 , v0 ∈ L2n,div , e0 ∈ L1 , e0 ≥ C ∗ > 0 in Ω, h ∈ L1 (0, T ).
Then for all T > 0, 0 ≤ λ < 1 there is suitable weak solution {v, p, e}
1,2
v ∈ C (0, T ; L2weak ) ∩ L2 (0, T ; Wn,div
)
tr v ∈ L2 (0, T ; L2 (∂Ω))
5
5
p ∈ L 3 (0, T ; L 3 )
e∈
L∞ (0, T ; L1 )
(p +
∩
´
Lm (Q),
Ω p(t, x)dx = g (t)
∇e ∈ Ln (Q) with m
10
10
|v|2
)v ∈ L 9 (0, T ; L 9 )
2
Málek (Charles University in Prague)
∈ h1, 53 ), n ∈ h1, 54 )
5
5
D (v)v ∈ L 4 ([0, T ]; L 4 )
Implicit fluids & Orlicz spaces
July 6, 2010
43 / 54
Newtonian incompressible heat-conducting fluids
Weak vrs Suitable weak solutions
Governing equations
D(v)
div v = 0
v,t + div(v ⊗ v) = −∇p + div ν(. . . )D
|v|2 |v|2 D(v) v
e+
+ div e + p +
v − div(κ(. . . )∇e) = div ν(. . . )D
2 ,t
2
Formulation of the second law of thermodynamics
D(v)|2
e,t + div(ev) − div(κ(e)∇e) ≥ ν(e)|D
equivalent to
D(v)|2 ≤ div(ν(e)D
D(v)v − (p + 12 |v|2 )v)
( 12 |v|2 ),t + ν|D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
44 / 54
Newtonian incompressible heat-conducting fluids
Energy estimates and their consequences
D(v)
div v = 0
v,t + div(v ⊗ v) = −∇p + div ν(. . . )D
|v|2 |v|2 D(v) v
e+
+ div e + p +
v − div(κ(. . . )∇e) = div ν(. . . )D
2 ,t
2
D(v)|2
e,t + div(ev) − div(κ(. . . )∇e)(≥) = ν(. . . )|D
´
Ω
´T
0
e+
|v|2 2 (t, x)dx
≤
´
Ω
e0 +
|v0 |2 dx
2
=⇒ e ∈ L∞ (L1 ) v ∈ L∞ (L2 )
D(v)|2 dx ≤ C
ν(. . . )|D
=⇒
∇v ∈ L2 (L2 )
D(v)|2 ≥ 0, =⇒ e > C ∗ a.e. , e ∈ Lm (Lm ) , ∇(e)(1−s)/2 ∈ L2 (L2 )
ν(. . . )|D
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
45 / 54
Newtonian incompressible heat-conducting fluids
Estimates for the pressure
Equation for the pressure:
D(v))
p = (−∆)−1 div div(v ⊗ v − ν(. . . )D
v ∈ L∞ (L2 ) and ∇v ∈ L2 (L2 ) =⇒ v ∈ L10/3 (L10/3 ) and p ∈ L5/3 (L5/3 )
No-slip BCs for NSEs: Lp maximal regularity for the evolutionary Stokes system
(Solonnikov ’77, Giga, Giga, Sohr ’85)
f ∈ Lp (Lq ) =⇒ v,t , ∇(2) v, ∇p ∈ Lp (Lq )
No-slip BC for generalized NSEs with v (e) does not hold.
Navier’s slip: v · n = 0 solutions of homogeneous Neumann problem for Laplace
equations are admissible
(p, div ϕ) = −(p, −∆h)
− ∆h = |p|α p
Integrable pressure exists for domains with Lipschitz boundary, etc.
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
46 / 54
Newtonian incompressible heat-conducting fluids
Further consequences of energy estimates
D(v)
div v = 0
v,t + div(v ⊗ v) = −∇p + div ν(. . . )D
|v|2 |v|2 D(v) v
e+
+ div e + p +
v − div(κ(. . . )∇e) = div ν(. . . )D
2 ,t
2
D(v)|2
e,t + div(ev) − div(κ(. . . )∇e)(≥) = ν(. . . )|D
∗
v,t ∈ L5/2 (W 1,5/2 ) = L−5/3 (W 1,−5/3 )
′
e,t ∈ L1 (W −1,q ) with q > 10
Aubin-Lions lemma and its generalization: v and e precompact in Lm (Lm )
for m ∈ [1, 53 )
Trace theorem and Aubin-Lions lemma: pre-compactness of v on ∂Ω
Two steps in the proof of existence
Stability of the system w.r.t. weakly converging sequences
Constructions of approximations (several levels), derivation of uniform
estimates, weak limits - candidates for the solutions, taking limits in
nonlinearities
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
47 / 54
Newtonian incompressible heat-conducting fluids
Newtonian and Fourier fluids - unbounded ν and κ
α, β > 0:
ν(e) ∼ (1 + e α )
κ(e) ∼ (1 + e β )
NSF: ν decreases with increasing e
TKE: ν increases with increasing k
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
a
)
ν(e) = ν0 exp( b+e
√
ν(k, ℓ) = ν0 + ν1 ℓ k
July 6, 2010
48 / 54
Newtonian incompressible heat-conducting fluids
Conjecture - Bulı́ček, Lewandowski, Málek
ν(e) := ν0 e α
and
κ(e) := µ0 e α .
(1)
Conjecture. Let α ∈ R, ν and µ are of the form (1). Then there exists a
δ > 0 and C ∗ > 0 such that for any suitable weak solution (v, p, e) to NSF
with unbounded material coefficients the following implication holds:
If
ˆ ˆ
0
−1
B1 (0)
D(v)|2 dx dt ≤ δ
ν(e)|D
then
|v(t, x)| ≤ C ∗
1
in (− , 0) × B 1 (0).
2
2
For α ≡ 0: NSEs - Conjecture holds (CKN ’82, Vasseur ’07). Statement:
If Conjecture holds for α ≥ 61 then the corresponding suitable weak
solution has bounded velocity
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
49 / 54
Newtonian incompressible heat-conducting fluids
Scaling property of NSF
(v, p, e) solve NSF on some neighborhood of (0, 0): (−ℓA0 , 0) × Bℓ0 (0) with some
A > 0 and ℓ0 > 0. Then
vℓ (t, x) := ℓB v(ℓA t, x)
with
A :=
pℓ (t, x)
2 − 2α
,
1 − 2α
:= ℓ2B p(ℓA t, x)
B :=
1
1 − 2α
eℓ (t, x) := ℓ2B e(ℓA t, ℓx)
α 6=
1
2
solves NSF in (−1, 0) × B1 (0). Conjecture applied on (vℓ , eℓ ) leads to
δ≥
=
ˆ
0
−1
ˆ 1
−1
ˆ
D(vℓ )|2 dx dt
ν(kℓ )|D
ˆ
D(v(ℓA t, ℓx))|2 dx dt
ℓ2Bα+2B+2 (k(ℓA t, ℓx))α |D
B1 (0)
6α−1
= ℓ 1−2α
B1 (0)
ˆ 0
−ℓA
Málek (Charles University in Prague)
ˆ
Bℓ (0)
D(v)|2 dx dt.
k α |D
Implicit fluids & Orlicz spaces
July 6, 2010
50 / 54
Newtonian incompressible heat-conducting fluids
Existence result - unbounded ν and κ
Theorem 2. (M. Bulı́ček, R. Lewandowski, J. Málek, 2010)
ν, κ fulfil the growth condition
β≥0
0≤α<
Assume that
2β
2
+
5
3
Then for any set of data there exists (suitable) weak solution (v, p, e) to the
system in consideration, completed by Navier’s slip boundary conditions, such that
1,2
v ∈ C (0, T ; L2weak ) ∩ L2 (0, T ; Wn,div
)
p ∈ Lq (0, T ; Lq )
tr v ∈ L8/5 (0, T ; L8/5 (∂Ω))
q < min{5/3, 2 − 2α/(α + β + 5/3)}
β+1
2
′
′
v,t ∈ Lq (0, T ; Wn−1,q ) e,t ∈ M(0, T ; W −1,10/9 ) E,t ∈ L1 (0, T ; W −1,10/9 )
e ∈ L∞ (0, T ; L1 ) ,
e≥0
and
(1 + e)s − 1 ∈ L2 (0, T ; W 1,2 ) s <
lim (kv(t) − v0 k22 + ke(t) − e0 k1 ) = 0
t→0+
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
51 / 54
Newtonian incompressible heat-conducting fluids
Maximal L2 -regularity for Stokes-Fourier system
Navier-Stokes sytem
div v = 0
v,t + div(v ⊗ v) − div(2ν0D(v)) + ∇p = F
Maximal Lq -regularity for the evolutionary (linear) Stokes system
div v = 0
v,t − div(2ν0D (v)) + ∇p = F
F ∈ Lr (0, T ; Lr (Ω)d ) =⇒ v,t , ∇p, ∇2 v ∈ Lr (0, T ; Lr (Ω))
Q: Maximal Lq -regularity for the evolutionary (non-linear) Stokes-Fourier
div v = 0
D(v)) + ∇p = F
v,t − div(ν(e)D
D(v)|2
e,t − div(κ(e)∇e) = ν(e)|D
Simplifications: periodic problem, κ(e) = 1, ν0 ≤ v (e) ≤ ν1 , r = 2
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
52 / 54
Newtonian incompressible heat-conducting fluids
L2 -maximal regularity like result for Stokes-Fourier Eqs
Theorem 3. (M. Bulı́ček, P. Kaplický, J. Málek Applicable Analysis 2010)
Let d ≥ 2. Let
√
e0 ∈ W 1,2 (Ω) e0 ≥ emin
F ∈ L2 (0, T ; L2 (Ω)d )
ˆ
1,2
d
1,2
d
u = 0}
v0 ∈ Wdiv (Ω) := {u ∈ W (Ω) ; div u = 0,
Ω
C 0,1 (R+ ) fulfills
ν ′ (s)
Assume that ν ∈
(ε > 0)
2
1
−
≤
≤
15(s − emin + ε)
ν(s)
40(s − emin + ε)
for all s ∈ (emin , ∞)
Then there exists a triple (v, e, p) that solves (SF) such that
1,2
v ∈ L∞ (0, T ; Wdiv
(Ω)d ) ∩ L2 (0, T ; W 2,2 (Ω)d ) ∩ W 1,2 (0, T ; L2 (Ω)d )
√
e∈L
d+2
d
∞
(0, T ; W 2,
e ∈ L (0, T ; W
1,2
Málek (Charles University in Prague)
d+2
d
(Ω)) ∩ W 1,
(Ω))
d+2
d
(0, T ; L
2
d+2
d
p ∈ L (0, T ; W
Implicit fluids & Orlicz spaces
(Ω))
1,2
(Ω))
July 6, 2010
53 / 54
Newtonian incompressible heat-conducting fluids
Example
−
2
ν ′ (s)
1
≤
≤
15(s − emin + ε)
ν(s)
40(s − emin + ε)
If ν(e) = ν0 exp(
for all s ∈ (emin , ∞)
a
) that the above conditions holds if emin > 2a − b
b+e
Málek (Charles University in Prague)
Implicit fluids & Orlicz spaces
July 6, 2010
54 / 54
Download