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Updated: Jun 28, 2026
09:37
Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole
Published on: August 26, 2019
Highly symmetric travelling waves in pipe flow
Chris C T Pringle1, Yohann Duguet, Rich R Kerswell
1Department of Mathematics, University of Bristol, University Walk, Bristol, UK. chris.pringle@bristol.ac.uk
Summary
Researchers discovered new travelling waves (TWs) in pipe flow, offering fresh insights into fluid dynamics. These unstable waves exhibit higher wall shear stress at lower Reynolds numbers, advancing our understanding of flow transitions.
Area of Science:
- Fluid dynamics
- Turbulence theory
Background:
- Osborne Reynolds' 125-year-old studies on pipe flow transitions are being revisited.
- Finite-amplitude travelling waves (TWs) have been theoretically discovered, sparking renewed interest.
Purpose of the Study:
- To describe two new classes of travelling waves (TWs) in pipe flow.
- To investigate their fundamental nature within the hierarchy of exact solutions.
Main Methods:
- Theoretical analysis of fluid flow dynamics.
- Identification of TWs with specific symmetry properties.
Main Results:
- Two new classes of TWs, M-class and N-class, were identified.
- These TWs exhibit higher wall shear stresses and occur at lower Reynolds numbers.
- M-class TWs show a double-layered streak structure; N-class TWs feature exterior fast streaks and interior slow streaks.
Conclusions:
- The newly discovered TWs provide fundamental insights into pipe flow dynamics.
- They offer a deeper understanding of transitional phenomena and exact solutions in fluid mechanics.
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