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Updated: Jul 17, 2026
09:37
Visualization of Flow Field Around a Vibrating Pipeline Within an Equilibrium Scour Hole
Published on: August 26, 2019
Turbulent flow in smooth and rough pipes.
J J Allen1, M A Shockling, G J Kunkel
1Department of Mechanical Engineering, New Mexico State University, Las Cruces, NM 88003, USA.
Summary
New research reveals complex scaling in smooth and rough pipe flow, challenging traditional models. Findings include a new friction factor relationship and support for outer-layer similarity hypotheses in turbulent flows.
Area of Science:
- Fluid dynamics
- Turbulence research
- Experimental fluid mechanics
Background:
- Traditional pipe flow models, like the Moody diagram, assume monotonic friction factor relationships.
- Previous understanding of smooth and rough pipe flow scaling may be incomplete.
Purpose of the Study:
- To investigate complex scaling behaviors in smooth and rough pipe flows.
- To develop new friction factor relationships and validate turbulence hypotheses.
Main Methods:
- Experiments conducted on smooth and honed rough pipes.
- Analysis of pressure gradients, velocity profiles, and turbulence intensities.
- Outer-layer scaling and spectral analysis of flow data.
Main Results:
- A new friction factor relationship for smooth pipes was identified.
- Velocity profiles showed power-law and logarithmic regions.
- Rough pipe flow exhibited an inflectional friction factor relationship in the transitionally rough regime.
- Outer-layer similarity hypothesis was supported for rough-walled flows.
Conclusions:
- The study reveals more complex scaling in pipe flow than previously understood.
- New findings challenge the traditional Moody diagram for certain flow regimes.
- A generalized transition from smooth to fully rough flow was proposed based on experimental data.
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