Ja n 19 99 Intermittency in turbulence
نویسنده
چکیده
We derive from the Navier-Stokes equation an exact equation satisfied by the dissi-pation rate correlation function, < ǫ(x + r, t + τ)ǫ(x, t) >, which we study in the equal time limit. We exploit its mathematical similarity to the corresponding equation derived from the 1-dimensional stochastic Burgers equation to show that the main intermittency exponents are µ 1 = 2 − ζ 6 and µ 2 = 2 ˜ z 4 − ζ 4 , where the ζ's are exponents of velocity structure functions and˜z 4 is a dynamical exponent characterizing the 4th order structure function. We discuss the role of sweeping and Galilean invariance in determining the intermittency exponents.
منابع مشابه
ar X iv : h ep - p h / 99 01 40 8 v 1 2 6 Ja n 19 99 HZPP - 9901 Jan . 25 , 1999 On the Intermittency and Chaos in High Energy Collisions 1
It is shown that an event sample from the Monte Carlo simulation of a random cascading α model with fixed dynamical fluctuation strength is intermittent but not chaotic, while the variance of dy-namical fluctuation strength in different events will result in both the intermittency and the chaoticity behavior. This shows that fractality and chaoticity are two connected but different features of ...
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