为探究液滴撞击深池上覆油膜特性，通过实验和理论方法研究撞击过程中的空腔演化动力特性，构建了多界面模型。结果表明：液滴-油膜-液池的不相溶特性导致更复杂的空腔演化过程，对于较小的弗劳德数Fr条件下，子液滴的产生原因是向下射流发生Rayleigh-Plateau不稳定性。对于大Fr条件下，撞击后形变液滴收缩导致的Rayleigh-Plateau不稳定性是导致子液滴形成的主要原因；由于不相溶界面上的切应力影响，空腔初始扩展速度随着形变界面数量增加而减小；对于薄液膜，由于未考虑油膜-深池界面形变的界面能，其无量纲空腔深度d′与Fr之间关系不满足经典关系d′~。而对于厚液膜，其撞击过程可被视为水滴撞击油池，实验观测满足经典关系；采用多界面模型求解获得的有效空腔深度与Fr之间关系满足~。

In order to explore the crater characteristics of droplet impacting on the oil film floating above the deep pool, experimental study and theoretical analysis were used to investigate cavity dynamics,, and a multi-interfaces model was proposed. The results show that that the immiscible properties of the droplet-oil film-liquid pool leads to a more complex cavity evolution process. It is concluded that for a smaller Froude number Fr, the daughter droplets are mainly generated by the Rayleigh-Plateau instability of the downward jet. For large Fr, the Rayleigh-Plateau instability due to the shrinkage of deformed droplets is the main reason of daughter droplets formation. Due to the effect of shear stress on the immiscible interfaces, the initial expansion rate of the cavity decreases with the increase in the number of deformed interfaces. For the thin liquid film, since the interfacial energy of the oil film-deep pool interface deformation is incorporated, the dimensionless depth of the cavity d′ and Fr does not satisfy the classical relationship with d′ ~ . In contrast, for the thick liquid film, its impact process can be regarded as a droplet impacting the oil deep pool, and the experimental observation satisfies the classical relationship. Moreover, the relationship between the effective cavity depth and Fr obtained by using the multi-interfaces model roughly meets the scaling law ~ .