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