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Updated: Apr 5, 2026
11:00
Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
12.0K
Multifractal-cascade model for inertial and dissipation ranges based on the wavelet reconstruction method
Long Zhou1, Cornelia Rauh1, Antonio Delgado1
1Institute of Fluid Mechanics (LSTM), Friedrich-Alexander University of Erlangen-Nürnberg, 91058, Germany.
Summary
This study introduces a discrete wavelet method to model turbulent velocity fields. The findings suggest that turbulent dissipation rate is dependent on the Reynolds number, aligning with experimental data.
Area of Science:
- Physics
- Fluid Dynamics
- Turbulence
Background:
- Turbulent velocity fields are complex phenomena.
- Understanding energy dissipation is crucial in fluid dynamics.
Purpose of the Study:
- To construct turbulent velocity fields using discrete wavelets.
- To model inertial and dissipation ranges in turbulence.
- To investigate the relationship between dissipation rate and Reynolds number.
Main Methods:
- Utilizing discrete wavelet transforms for field construction.
- Employing the p model for inertial range velocity increments.
- Applying a dissipation model based on Foias et al. (exp(-gk)).
Main Results:
- Computed lengths of inertial and dissipation ranges based on construction levels.
- Estimated Reynolds number for the cascade process.
- Dissipation rate calculations align with experimental data.
Conclusions:
- The proposed model successfully represents turbulent velocity fields.
- The dissipation rate is not independent of the Reynolds number.
- This work provides insights into turbulence modeling and energy dissipation.
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