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Updated: Jul 14, 2026
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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
A deterministic model for the sublayer streaks in turbulent boundary layers for application to flow control
Peter W Carpenter1, Karen L Kudar, Reza Ali
1School of Engineering, University of Warwick, Coventry CV4 7AL, UK. pwc@eng.warwick.ac.uk
Summary
A new theoretical model explains turbulent boundary layer streaks using a vorticity source. The model accurately predicts streak spacing and the effects of wall compliance, offering insights into the bursting cycle.
Area of Science:
- Fluid dynamics
- Turbulence research
- Boundary layer theory
Background:
- Turbulent boundary layers exhibit complex structures, including sublayer streaks.
- Understanding these streaks is crucial for predicting and controlling turbulent flows.
- Existing models often lack a simple, deterministic approach to streak generation.
Purpose of the Study:
- To develop a simple, deterministic theoretical model for sublayer streaks in turbulent boundary layers.
- To investigate the influence of factors like pressure gradient, Reynolds number, and wall compliance on streak characteristics.
- To provide a theoretical framework for the quasi-periodic bursting cycle in turbulent flows.
Main Methods:
- Utilizing an analogy with Klebanoff modes.
- Employing a fictitious body force as a vorticity source to generate streamwise vortices.
- Developing a theoretical model for the bursting cycle involving streaks, plane waves, and oblique waves.
Main Results:
- The model generates streamwise vortices responsible for sublayer streaks.
- The strongest streaks predicted by the model match experimentally observed mean streak spacing.
- Theoretical predictions for wall compliance effects align well with experimental data.
Conclusions:
- The proposed model offers a simplified, deterministic explanation for sublayer streaks.
- The model successfully captures key streak characteristics and their dependence on flow parameters.
- The theoretical bursting cycle provides a coherent mechanism linking vortex generation, streak formation, and wave interactions.
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