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Updated: Apr 5, 2026
13:02
Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
13.2K
Intermittent Lagrangian velocities and accelerations in three-dimensional porous medium flow
M Holzner1, V L Morales2, M Willmann3
1Institute of Environmental Engineering, ETH Zurich, Wolfgang-Pauli-Strasse 15, 8093 Zürich, Switzerland.
Summary
Particle movement in porous media shows intermittent Lagrangian velocity and acceleration. This intermittency, driven by pore structure, influences transport and can be modeled using continuous-time random-walks.
Area of Science:
- Fluid dynamics
- Porous media physics
- Complex systems analysis
Background:
- Lagrangian velocity and acceleration intermittency are crucial for understanding transport in diverse complex systems.
- Porous media flow exhibits unique transport characteristics influenced by pore-scale geometry.
Purpose of the Study:
- To investigate Lagrangian velocity and acceleration intermittency in a 3D porous medium.
- To link observed flow behaviors to pore geometry and connectivity.
- To develop a predictive model for particle transport.
Main Methods:
- High-resolution optical particle tracking was employed to capture detailed 3D Lagrangian velocities and accelerations.
- Analysis focused on transitions near pore throats and flow variability within pore bodies.
- Particle dispersion and propagator behavior were examined.
Main Results:
- Sharp transitions in flow dynamics were observed near pore throats.
- Low flow variability was noted within pore bodies.
- Stretched exponential distributions characterized Lagrangian velocity and acceleration, featuring a low-velocity peak.
- Superlinear particle dispersion and double-peak propagators were identified.
Conclusions:
- Pore geometry and connectivity dictate Lagrangian velocity distributions.
- A continuous-time random-walk model effectively explains the observed Lagrangian flow and transport behaviors.
- The study provides a framework for understanding transport in complex porous media.
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