- Series
- CDSNS Colloquium
- Time
- Friday, March 4, 2022 - 1:00pm for 1 hour (actually 50 minutes)
- Location
- Skiles 05
- Speaker
- Victor Vilaça Da Rocha – Georgia Tech – vrocha3@gatech.edu
- Organizer
- Victor Vilaça Da Rocha
Different ways have been introduced to define intermittency in the theory of turbulence, like for example the non-gaussianity, the lack of self-similarity or the deviation of the theory of turbulence by Kolmogorov from 1941.
The usual tool to measure intermittency is the flatness, a measure of the variation of the velocity at small scale, using structure functions in the spatial domain, or high-pass filters in the frequency domain. However, these two approaches give different results in some experiences.
The goal here is to study and compare these two methods and show that the result depends on the regularity of the studied function. For that purpose, we use Riemann's non-differentiable functions. To motivate this choice, we'll present the link between this function, the vortex filament equation, and the multifractal formalism.
This is a work in collaboration with Daniel Eceizabarrena (University of Massachusetts Amherst) and Alexandre Boritchev (University of Lyon)