Submitted:
23 December 2023
Posted:
26 December 2023
Read the latest preprint version here
Abstract
Keywords:
1. Introduction
1. The theory
1.1. The Euler ensemble and its continuum limit
1.2. Small Euler ensemble at large N
2. The big Euler ensemble as a Markov process
2.1. Numerical Simulations
2.2. Scaling variables in continuum limit
3. Vorticity correlation
3.1. Exact relation with conditional probability density
3.2. Extracting conditional distribution from numerical data
3.3. Final results for the energy spectrum
4. Comparison with real and numerical experiments
5. Conclusions
- We found continuum limit of distribution of scaling variables (33),(38) in the small Euler ensemble.
- The local slope of energy spectrum is , not counting jumps. The average slope is . The K41 spectrum lies in between.
- This universal energy spectrum depending on corresponds to the effective spatial scale , or in notations of [9].
- The decay at a given time goes only at small enough wavelengths. At a fixed wavelength, the decay stops after some critical time, inversely proportional to the wavelength square.
- With the cutoff of our spectrum at the small wavelength corresponding to initial energy pumping (), we obtain discrete levels of the effective index . During decay, the index jumps down from one level to another, with level spacing increasing with time. These levels are universal numbers, given by the table (111).
Data Availability Statement
Acknowledgments
Appendix A Algorithms
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