Analysis of fluid flow and particle transport in evaporating droplets exposed to infrared heating
Analysis of fluid flow and particle transport in evaporating droplets exposed to infrared heating
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DOI：
10.1016/j.ijheatmasstransfer.2013.09.012
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发表时间：
2014-01-01
影响因子：
5.2
通讯作者：
Singh, Anugrah
中科院分区：
文献类型：
--
作者：
Thokchom, Ashish Kumar;Gupta, Abhishek;Singh, Anugrah
采用实验和数值模拟相结合的方法，研究了外辐射作用下蒸发液滴内部流体流动和颗粒输运特性。在这项研究中，我们已经表明，通过改变自由表面温度，我们可以修改液滴内的流体流动轮廓，因此溶质颗粒在基板上的沉积模式。采用粒子图像测速技术（PIV）测量了蒸发液滴内部的速度场和颗粒浓度场。实验在含有分散的聚苯乙烯颗粒的小固着水滴上进行。为了避免在使用3D液滴的Ply测量中遇到的图像校正问题，我们的实验在夹在两个非润湿表面之间的等效盘形2D液滴上进行，而液滴的基部固定到润湿表面。通过红外（IR）光加热液滴的顶表面。液滴表面温度由热电偶测量。研究了蒸发过程中的速度场、颗粒浓度分布和颗粒沉积形态。我们还通过求解连续性、动量和能量输运方程进行了数值模拟。由浮力和Marangoni对流计算的速度分布与实验定性一致。(C)2013爱思唯尔有限公司保留所有权利。
Analysis of fluid flow and particle transport inside evaporating droplets exposed to external radiation was carried out by experiments and numerical simulations. In this study, we have shown that by altering the free surface temperature we can modify the fluid flow profile inside the droplet and hence the deposition pattern of solute particles on the substrate. The fluid velocity and particle concentration profiles inside the evaporating droplet were measured by Particle Image Velocimetry (PIV) technique. Experiments were carried out on a small sessile water droplet containing dispersed polystyrene particles. To avoid problem of image correction encountered in Ply measurements with 3D droplets, our experiments were performed on an equivalent disc shaped 2D drop sandwiched between two non-wetting surfaces, while the base of the droplet was pinned to a wetting surface. The top surface of the droplet was heated by Infrared (IR) light. The temperature of droplet surface was measured by thermocouples. The velocity field, particle concentration profile and particle deposition patterns were studied during evaporation process. We have also performed numerical simulations by solving continuity, momentum and energy transport equations. The computed velocity profiles resulting from buoyancy and Marangoni convection are in qualitative agreement with the experiments. (C) 2013 Elsevier Ltd. All rights reserved.