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arXiv · 1510.09097

Optimized Setup for 2D Convection Experiments in Thin Liquid Films

Michael Winkler·Markus Abel
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Abstract

We present a novel experimental setup to investigate two-dimensional thermal convection in a freestanding thin liquid film. We develop a setup for the reproducible generation of freestanding thin liquid films. Such films can be produced in a controlled way on the scale of 5 to 1000 nanometers. Our primary goal is to investigate the statistics of reversals in Rayleigh-Bénard convection with varying aspect ratio; here numerical works are quite expensive and 3D experiments prohibitively complicated and costly. However, as well questions regarding the physics of liquid films under controlled conditions can be investigated, like surface forces, or stability under varying thermodynamical parameters. The thin liquid film has a well-defined and -chosen chemistry in order to fit our particular requirements, it has a thickness to area ratio of approximately 10^8 and is supported by a frame which is adjustable in height and width to vary the aspect ratio from 0.16 to 10. The top and bottom frame elements can be set to specific temperature within T= 15-55°C. The ambient parameters of the thin film are carefully controlled to achieve reproducible results and allow a comparison to experimental and numerical data.

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Michael Winkler, Markus Abel. 2015-10-30. Optimized Setup for 2D Convection Experiments in Thin Liquid Films. https://doi.org/10.1063/1.4950871

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