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Related Experiment Video

Updated: Apr 15, 2026

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow

Published on: February 27, 2016

Statistical conservation law in two- and three-dimensional turbulent flows.

Anna Frishman¹, Guido Boffetta², Filippo De Lillo²

¹Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100, Israel.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics

|April 15, 2015

Summary

This study confirms a statistical conservation law for particle pairs in turbulent flows. The average of particle separation raised to the power of flow dimensionality remains constant, validating turbulent flow models.

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Last Updated: Apr 15, 2026

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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section

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Area of Science:

Fluid Dynamics
Turbulence Theory
Statistical Mechanics

Background:

Particle dynamics in turbulent flows are complex.
A proposed statistical conservation law for particle pairs in incompressible isotropic turbulent flows exists.
This law relates particle separation to flow dimensionality.

Purpose of the Study:

To provide evidence for the statistical conservation law of particle pairs in turbulent flows.
To investigate the limits of this conservation law.
To explore related fluctuation relations and conservation laws in different dimensions.

Main Methods:

Direct numerical simulations of two- and three-dimensional turbulence.
Analysis of data from a 3D laboratory experiment.
Investigating particle separation R(t) and its statistical properties.

Main Results:

Evidence supporting the statistical conservation law was found in 2D and 3D simulations.
Conservation is lost when particles exit the linear flow regime.
A fluctuation relation of the Gallavotti-Cohen type was observed in 2D.
In 3D experiments, a power-law conservation law was predicted but not fully realized.

Conclusions:

The statistical conservation law is supported by simulations.
The conservation law serves as a validation tool for numerical and experimental studies of turbulence.
Deviations from the conservation law indicate non-linear flow regimes or experimental limitations.