Intermittency and Anomalous scaling in turbulence - Victor S. L'vov ...
Intermittency and Anomalous scaling in turbulence - Victor S. L'vov ...
Intermittency and Anomalous scaling in turbulence - Victor S. L'vov ...
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• Exact “Dissipative-bridge” relationships, (L’vov-Procaccia-96)<br />
NSE:<br />
∂v<br />
+ (v · ∇)v + ∇p = ν ∆v<br />
∂t<br />
⇒<br />
∂v<br />
∂t + P <br />
(v · ∇)v <br />
= ν ∆v<br />
P: transversal projector, Wr: r-separated velocity <strong>in</strong>crement.<br />
NSE for Wr schematically :<br />
Wr ∂Wr<br />
∂t + Wr P <br />
<br />
(Wr · ∇)Wr<br />
∂Wr<br />
∂t + P <br />
<br />
(Wr · ∇)Wr<br />
= ν ∆Wr ⇒<br />
= Wrν ∆Wr ⇒ −ν(∇Wr) ·(∇Wr) −ε(r) .<br />
Thus, <strong>in</strong>side of the average operator, 〈. . .〉, the viscous range object ε(r)<br />
can be evaluated as the <strong>in</strong>ertial range object Wr P <br />
<br />
(Wr · ∇)Wr<br />
ε(r) ⇒ W3 r<br />
r<br />
W 3 r /r:<br />
⇒ µn = n − ζ3n ⇒ µ2 = 2 − ζ6 0.3 ÷ 0.4<br />
Exact “dissipative-bridge” relations µn = n − ζ3n<br />
are known <strong>in</strong> liter-<br />
ature as a consequence of Kolmogorov “Ref<strong>in</strong>ed Similarity” hypothesis.<br />
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