Journal ArticleDOI
Onset of surface-tension-driven Benard convection
TLDR
In this article, an experimental investigation of the onset of convection in shallow fluid layers heated uniformly from below and cooled from above by an air layer has been made, and it has been shown that if the depth of the silicone layer is smaller than 2 mm, then convection takes place in two stages.Abstract:
An experimental investigation of the onset of convection in shallow fluid layers heated uniformly from below and cooled from above by an air layer has been made. If the depth of the silicone layer is smaller than 2 mm the onset of convection takes place in two stages. There is first a weak pattern, which is characterized by its appearance at ever smaller temperature gradients as the depth of the fluid is decreased. When the temperature difference across the fluid is increased a second strong pattern forms near the predicted critical Marangoni number. The cells in this pattern are hexagonal and seem to be what one has always referred to as Benard cells. The temperature gradient at which this pattern appears increases with decreased depth. The heat transfer through the fluid has been measured. The critical temperature gradient for the formation of the hexagonal pattern has been determined from the break of the heat transfer curve.read more
Citations
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Experiments on thermocapillary instabilities
TL;DR: In this article, a review summarizes recent experimental studies of instabilities in free-surface flows driven by thermocapillarity, and two broad classes are considered, depending upon whether the imposed temperature gradient is perpendicular (Marangoni-convection instability) or parallel (thermocapillary-convolution instability) to the free surface.
Journal ArticleDOI
Surface-tension-driven bénard convection in small containers
E. L. Koschmieder,S. A. Prahl +1 more
TL;DR: In this article, the onset and the form of surface-tension-driven convection in three different small circular and one small square containers was studied experimentally, and the onset of convection was characterized by a steep increase of the critical Marangoni number with decreasing aspect ratio.
Journal ArticleDOI
Linear stability analysis of Bénard–Marangoni convection in fluids with a deformable free surface
TL;DR: In this article, the stability analysis of the Benard-marangoni problem in a layer of fluid with a deformable free surface is considered, restricted to fixed values of the Prandtl and Biot numbers in order to determine the role of the Crispation number on convection.
Journal ArticleDOI
Square cells in surface-tension-driven Bénard convection: experiment and theory
TL;DR: In this article, the convective flow in a thin liquid layer with a free surface heated from below is studied using a combination of accurate experiments with silicone oil (v=0.1 cm2 s−1) and high-resolution direct numerical simulations of the timedependent governing equations.
Journal ArticleDOI
Low-Temperature Soft-Cover Deposition of Uniform Large-Scale Perovskite Films for High-Performance Solar Cells.
Fei Ye,Wentao Tang,Fengxian Xie,Maoshu Yin,Jinjin He,Yanbo Wang,Han Chen,Yinghuai Qiang,Xudong Yang,Liyuan Han +9 more
TL;DR: A scalable low-temperature soft-cover deposition (LT-SCD) method is presented, where the thermal convection-induced defects in perovskite films are eliminated through a strategy of surface tension relaxation, which provides a new non-spin-coating route to the deposition of large-area uniform perovkite films for both rigid and flexible perovSKite devices.
References
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Journal ArticleDOI
LIX. On convection currents in a horizontal layer of fluid, when the higher temperature is on the under side
Journal ArticleDOI
On convection cells induced by surface tension
TL;DR: In this paper, a mechanism was proposed by which cellular convective motion of the type observed by H. Benard, which hitherto has been attributed to the action of buoyancy forces, can also be induced by surface tension forces.
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On cellular convection driven by surface-tension gradients: effects of mean surface tension and surface viscosity
L. E. Scriven,C. V. Sternling +1 more
TL;DR: In this article, the onset of steady, cellular convection driven by surface tension gradients on a thin layer of liquid is examined in an extension of Pearson's (1958) stability analysis.
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Surface tension and buoyancy effects in cellular convection
TL;DR: In this article, a Fourier series method has been used to obtain the eigenvalue equation for the case where the lower boundary surface is a rigid conductor and the upper free surface is subject to a general thermal condition.
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Surface Tension as the Cause of Bénard Cells and Surface Deformation in a Liquid Film
TL;DR: Benard as mentioned in this paper observed a cellular deformation produced on the free surface of a liquid film the bottom surface of which (in contact with a floor) was uniformly heated and hotter than its top surface.