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Updated: Dec 25, 2025
11:51
Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
9.1K
Behavior of Isolated Disturbances Superimposed on Laminar Flow in a Rectangular Pipe
Summary
This study investigated turbulent-like disturbances in laminar flow using dye injection. A functional relationship was found between disturbance velocity ratio, distance, and Reynolds number.
Area of Science:
- Fluid Dynamics
- Experimental Fluid Mechanics
Background:
- Laminar flow is typically smooth and orderly.
- Understanding disturbances within laminar flow is crucial for predicting fluid behavior in various engineering applications.
Purpose of the Study:
- To investigate the behavior of an isolated turbulent-like disturbance in laminar flow.
- To establish a functional relationship between key parameters characterizing the disturbance's propagation.
Main Methods:
- Experiments were conducted in a horizontal transparent rectangular pipe.
- A dye mass was injected to create a disturbance, and time-distance measurements were taken for its front and rear.
- Flow rate was controlled to calculate the Reynolds number.
Main Results:
- A functional relationship was identified among three variables: the ratio of the rear to front disturbance velocity (U), distance from the origin (X), and Reynolds number (R).
- The study provides quantitative data on how such disturbances evolve in laminar flow.
Conclusions:
- The observed relationship offers insights into the dynamics of transitional flow phenomena.
- This research contributes to the understanding of disturbance propagation in otherwise laminar flows.
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