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Enhanced droplet spreading due to thermal fluctuations
1Department of Mechanical Science and Engineering, College of Engineering, University of Illinois at Urbana-Champaign, 1206 West Green Street, Urbana, IL 61801, USA. College of Medicine at Urbana-Champaign, University of Illinois at Urbana-Champaign, USA.
Summary
Stochastic stresses from thermal fluctuations enhance liquid drop spreading. Atomistic simulations confirm that these stresses increase the spreading rate beyond standard lubrication predictions, validating a stochastic lubrication equation.
Area of Science:
- Fluid dynamics
- Statistical physics
- Materials science
Background:
- The standard lubrication equation describes thin liquid film dynamics.
- Thermal fluctuations can introduce stochastic stresses.
- These stresses may increase liquid drop spreading rates.
Purpose of the Study:
- To investigate the effect of stochastic stresses on liquid drop spreading.
- To quantitatively assess the accuracy of the stochastic lubrication equation.
- To examine a regime where enhanced spreading is predicted.
Main Methods:
- Atomistic simulations of a spreading liquid drop.
- Comparison of simulation results with standard and stochastic lubrication equations.
Main Results:
- Atomistic simulations showed increased drop spreading rates.
- The observed spreading rate exceeded predictions from standard lubrication equations.
- The stochastic lubrication equation accurately predicted the enhanced spread rate.
Conclusions:
- Stochastic stresses significantly influence liquid drop dynamics.
- The stochastic lubrication equation provides a more accurate model for spreading under thermal fluctuations.
- This work validates theoretical models with atomistic simulations.
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