采用复合水平集法和流体体积法建立液滴冲击球形凹曲面的数值模型，通过分析计算结果揭示了液滴撞壁流动及破碎机制。研究表明：液滴的撞壁特性与液滴碰撞速度密切相关；液滴凹曲面撞壁与平面撞壁相比，铺展系数较小，回弹射流出现时间超前，回弹射流速度较大。量纲1分析得出：液滴的最大铺展系数和相对最大铺展速度与 Reynolds 数近似幂递增，液滴的相对最大射流长度与 Reynolds 数近似对数递增，液滴的相对最大射流速度与Reynolds数近似幂递减。对比分析现有液滴撞壁最大铺展系数理论解析模型，提出了液滴凹曲面撞壁最大铺展系数解析模型的发展方向。%In order to explore the mechanism of droplet impact on a spherical concave surface, a numerical model using the coupled level set and volume of fluid method was developed. The mechanism of droplet impact and breakup during spreading was obtained. The impact characteristics were closely related to impact velocity. Droplet impact on a spherical concave surface showed a smaller spread factor, earlier time of central normal jet and larger jet velocity than the impact on a flat surface. The maximum spread factor and relative maximum spread velocity increased exponentially with Reynolds number. The maximum length of jet increased logarithmically with Reynolds number. The maximum jet velocity decreased exponentially with Reynolds number. Through comparison of theoretical analysis models of maximum spread factor, the development direction of analysis model of maximum spreading factor of droplet impact on a concave surface was presented.
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