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Updated: May 21, 2026
11:51
Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Particle-accumulation structures in periodic free-surface flows: inertia versus surface collisions
Hendrik C Kuhlmann1, Frank H Muldoon
1Vienna University of Technology, Institute of Fluid Mechanics and Heat Transfer, 1040 Wien, Austria.
Summary
Particle inertia and free-surface collisions cause particle accumulation in liquid bridges. Collisions, not inertia, explain observed experimental patterns, revealing key physics in periodic flows.
Area of Science:
- Fluid dynamics
- Microgravity science
Background:
- Periodic free-surface flows are crucial in various applications, including materials processing and microgravity experiments.
- Understanding particle behavior in these flows is essential for controlling transport and deposition.
Purpose of the Study:
- To investigate the distinct roles of particle inertia and particle-free-surface collisions in thermocapillary liquid bridges.
- To determine the primary mechanism responsible for experimentally observed particle accumulation patterns.
Main Methods:
- Development of an analytical flow model for a thermocapillary liquid bridge.
- Evaluation of particle dynamics considering both inertia and free-surface collision effects.
- Comparison of model predictions with existing experimental data.
Main Results:
- Both particle inertia and free-surface collisions contribute to particle accumulation.
- These mechanisms operate on different timescales and produce distinct accumulation patterns.
- The analytical model, emphasizing collisions, accurately reproduces experimental observations.
Conclusions:
- Particle-free-surface collisions are the dominant factor driving the experimentally observed accumulation patterns in thermocapillary liquid bridges.
- The study highlights the importance of considering specific collision dynamics in predicting particle behavior in such flows.
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