Related Experiment Video
Updated: Dec 29, 2025
13:02
Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
12.8K
X-ray particle tracking velocimetry in liquid foam flow.
Tobias Lappan1, Alexander Franz2, Holger Schwab3
1Helmholtz-Zentrum Dresden-Rossendorf, Institute of Fluid Dynamics, 01328 Dresden, Germany. t.lappan@hzdr.de sascha.heitkam@tu-dresden.de.
Soft Matter
|February 5, 2020
Summary
This study introduces a novel X-ray method using 3D-printed tracers to measure liquid foam flow velocity and vorticity. This technique offers deeper insights into foam dynamics compared to traditional optical methods.
Area of Science:
- Fluid Dynamics
- Materials Science
- Imaging Techniques
Background:
- Optical methods for foam flow analysis are limited by measurement depth.
- Understanding liquid foam dynamics is crucial in various industrial applications.
Purpose of the Study:
- To develop and validate a novel X-ray radiography technique for measuring liquid foam flow velocity.
- To investigate foam flow behavior in both straight and curved channels using advanced imaging.
Main Methods:
- Additive manufacturing of custom 3D-printed stainless steel tracers.
- Utilizing X-ray radiography and image intensifiers for non-invasive imaging.
- Applying particle tracking velocimetry (PTV) algorithms for high-resolution trajectory analysis.
Main Results:
- Successfully measured foam flow velocity and vorticity with high spatial (0.2 mm) and temporal (25 fps) resolution.
- Observed distinct flow patterns, including rigid-body-like motion in curved sections.
- Detected foam structure relaxation in transition zones between straight and curved channel sections.
Conclusions:
- The developed X-ray method provides a robust approach for detailed foam flow characterization.
- The study offers new insights into the complex rheology and structural behavior of liquid foams.
- This technique enables deeper penetration measurements than conventional optical methods.
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