AI Article Synopsis
- The study demonstrates that the She and Lévêque model effectively explains density-weighted moments of the dissipation rate in supersonic turbulence.
- A method was created to measure two important parameters of the model—gamma, representing the scaling exponent, and d, indicating the dimensions of intermittent structures.
- The best-fit parameters obtained from simulations match direct measurements, validating the model's application in supersonic turbulence scenarios.
Article Abstract
We show that density-weighted moments of the dissipation rate, epsilonl, averaged over a scale l, in supersonic turbulence can be successfully explained by the She and Lévêque model [Phys. Rev. Lett. 72, 336 (1994)]. A general method is developed to measure the two parameters of the model, gamma and d, based directly on their physical interpretations as the scaling exponent of the dissipation rate in the most intermittent structures (gamma) and the dimension of the structures (d). We find that the best-fit parameters (gamma=0.71 and d=1.90) derived from the epsilonl scalings in a simulation of supersonic turbulence at Mach 6 agree with their direct measurements, confirming the validity of the model in supersonic turbulence.
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