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Fluorescent Marangoni Flows under Quasi-Steady Conditions
Cesar L Usma1, Sandrine Mariot1, Claire Goldmann1
1Université Paris-Saclay, CNRS, Laboratoire de Physique des Solides, 91405 Orsay, France.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 18, 2022
Summary
Researchers developed a fluorescent surfactant to visualize Marangoni flow dynamics in complex fluids. This method allows quantitative probing at interfaces and in bulk without invasive tracers, revealing unexpected container size dependencies.
Area of Science:
- Complex Fluids
- Interfacial Science
- Fluid Dynamics
Background:
- Marangoni flow is a complex phenomenon crucial in interfacial science.
- Monitoring Marangoni flow typically requires invasive tracers, limiting quantitative analysis.
Purpose of the Study:
- To develop a non-invasive method for visualizing and quantifying Marangoni flow dynamics.
- To investigate the influence of container dimensions on Marangoni flow using a novel fluorescent probe.
Main Methods:
- Synthesis and application of a pyrene-tailed fluorescent surfactant.
- Quasi-steady state monitoring of Marangoni flow at air-water interfaces and within bulk fluid.
- Quantitative analysis of fluorescent probe dynamics and visualization of recirculation flows.
Main Results:
- The fluorescent surfactant clearly visualizes the Marangoni zone without invasive tracers.
- Unexpected dependencies of the Marangoni zone on container size and water depth were observed.
- Recirculation flows were detected near the container bottom via fluorescence.
Conclusions:
- A novel fluorescent surfactant enables non-invasive, quantitative study of Marangoni flow.
- Container size and water depth significantly influence Marangoni flow dynamics.
- This fluorescent probe offers a versatile tool for studying complex fluid phenomena.
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