论文标题
在不同条件下液滴与热表面之间相互作用的实验和数值研究
Experimental And Numerical Studies Of Interaction Between Liquid Droplets And Hot Surfaces Under Different Conditions
论文作者
论文摘要
在本文中，已经对不同液滴与不同热金属表面的相互作用进行了实验和数值研究，并使用图和图片解释了所获得的结果。在100 fps的摄像机的帮助下，观察到了液滴冲击，扩散，分解和Leidenfrost现象。相互作用研究是在不同的表面温度和不同的液滴撞击速度下进行的。本研究选择了三种金属和三种液体。选择铜，铝和钢作为具有不同粗糙度因子和不同温度的金属，而在液体，甲醇，乙醇和煤油中（在某些部分也使用了水）。金属的选择是基于十个扩散率的特性，因为它影响了液滴和热金属表面之间的热相互作用。金属表面的温度范围从150°C到425°C，撞击速度范围在2.4-4.9 m/s的范围内。对于计算研究，使用了ANSYS Fluent R3-2019版本。使用流体量（VOF）方法进行了相互作用过程的数值研究，在2D几何瞬态模拟中求解Navier-Stokes和能量方程。在本文中研究并讨论了诸如表面温度，热通量和扩散比等参数。这项研究的输出将有助于更好地了解物理机制，并开发出有效喷雾冷却系统设计的新型模型。结果表明，在影响较低后，液滴散布的宽度与高韦伯数量相比，韦伯数量的值较低。对于不同的表面温度，液滴的扩散比几乎是恒定或均匀的，仅取决于表面粗糙度。
In the present paper, experimental and numerical studies of interaction between different liquid droplets with different hot metal surfaces had been carried out and the obtained results were interpreted using graphs and pictures. Droplet impact, spreading, break-up, and leidenfrost phenomenon were observed with the help of video camera at 100 fps. The interaction studies were done at different surface temperatures and different droplet impinging velocities. Three metals and three liquids were selected for the present study. Copper, Aluminium and Steel were selected as metals with different roughness factors and at different temperatures, while in liquid entities, Methanol, Ethanol and Kerosene (Water was also used in some portion) were selected. The selections of the metals were based on thethermal diffusivity property as it influences the thermal interaction between droplet and the hot metal surface. The temperature range of metal surface was kept from 150° C to 425°C and the impinging velocity range of droplets were in the range of 2.4 - 4.9 m/s. For computational studies Ansys Fluent R3-2019 version was used. Numerical study for the interaction process was carried out using Volume of Fluid (VOF) method, solving Navier-Stokes and energy equations in a 2D-geometry transient simulation. Parameters like surface temperature, heat flux, and spreading ratio with respect to Weber number change were investigated and discussed in the present paper. The output of this study will be useful to understand the physical mechanisms better and to develop novel models for effective spray cooling system designs. The results show that for a lower value of Weber number, after impact the droplets spread less wide compare to high Weber number. The spreading ratio of droplets was almost constant or uniform for different surface temperature and it depends only on the surface roughness.
