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Updated: Jul 17, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Asymptotic scaling in turbulent pipe flow
1Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, CA 91125, USA. mckeon@caltech.ecu
Summary
This study investigates turbulent pipe flow, revealing that asymptotic behavior indicating high Reynolds numbers appears at R+>5 x 10(3). This suggests an
Area of Science:
- Fluid Dynamics
- Turbulence Research
- Aerospace Engineering
Background:
- Turbulent pipe flow is a fundamental area of fluid dynamics research.
- Understanding asymptotic behavior at high Reynolds numbers is crucial for accurate flow modeling.
- Previous studies suggested different thresholds for observing such behaviors.
Purpose of the Study:
- To assess the streamwise velocity component in turbulent pipe flow for asymptotic behavior.
- To determine the critical Reynolds number (R+) at which high Reynolds number indicators emerge.
- To investigate the presence and characteristics of inertial scaling in the flow.
Main Methods:
- Analysis of the streamwise velocity component in turbulent pipe flow.
- Examination of mean velocity profiles, specifically the log law.
- Investigation of the second moment of the streamwise velocity component in outer and overlap regions.
- Comparison with spectral energy transfer and inertial subrange concepts.
Main Results:
- Asymptotic behavior indicative of high Reynolds numbers was observed.
- The mean velocity and second moment data align with inertial scaling.
- An 'inertial sublayer' in physical space was identified as a spatial analogue to the inertial subrange in the velocity spectrum.
- This behavior was consistently found for Reynolds numbers R+ > 5 x 10(3).
Conclusions:
- Turbulent pipe flow exhibits distinct asymptotic behavior at higher Reynolds numbers than previously assumed.
- The findings support the concept of an 'inertial sublayer' in physical space.
- The critical Reynolds number for observing these high Reynolds number effects is approximately R+ > 5 x 10(3).
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