滴状冷凝中液滴的脉动规律及分形分布模型中相邻两代液滴半径比参数The Pulsating Feature of the Dancing Droplets and Droplet Radius Ratio of Adjacent Generations in the Fractal Model of Dropwise Condensation
兰忠,马学虎,周兴东,宋天一
摘要(Abstract):
分析研究了滴状冷凝实验过程中液滴的随机运动行为以及液滴分布的分形特征,发现液滴的运动和分布与接触角及接触角滞后有关。得到了液滴分形分布模型中相邻两代液滴半径比与接触角滞后的关系式,该式计算结果与实验结果十分吻合。实验结果表明,在存在接触角滞后的表面上,液滴以脉动方式长大,导致液滴分布呈离散分代分布,并且,液滴脉动行为还受诱导因素的影响,在较强诱导因素作用的冷凝过程中,液滴分代呈明显的台阶分布;反之,在较弱的诱导条件下,分代特征不明显。液滴受接触角滞后影响而发生的脉动行为还表现为液滴偶然与随机的弹射。在液滴频繁脉动形成分代分布特征的过程中,液滴由接触角为前进角状态脉动到等体积下接触角为平衡角状态的可能性较大。
关键词(KeyWords): 滴状冷凝;分形分布;脉动;半径比
基金项目(Foundation): 国家自然科学基金(50376005,59906002)
作者(Author): 兰忠,马学虎,周兴东,宋天一
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