中文摘要：

对含可溶性活性剂的液滴在预置液膜上的非均匀铺展过程,基于润滑理论建立基态和扰动态下的液滴厚度、表面活性剂浓度和内部浓度的演化模型,应用非模态理论分析演化过程的稳定性,探讨活性剂溶解特性及典型参数对液滴演化特征的影响.研究表明：扰动波的引入有利于增强液滴演化的稳定性,且稳定程度与扰动波的波数呈正相关性;然而随扰动波数的持续增大,液滴演化的稳定性逐渐下降,直至失稳;相对于非溶性活性剂,可溶性活性剂减缓了液滴的铺展程度,增强了演化过程的稳定性;预置液膜厚度、Marangoni数、毛细力数及吸附系数的增大,均有利于液滴稳定演化,其中Marangoni效应和毛细力的影响较大,预置液膜厚度则主要增强液滴厚度演化的稳定性.

英文摘要：

For process of an ultrathin surfactant-laden droplet spreading on preset film,base state and disturbance evolution equations for film thickness,surfactant interfacial and bulk concentrations were established with lubrication approximation. Transient growth analysis（ TGA） was carried out to investigate stability of evolution process. Effects of surfactant solubility and typical parameters were discussed. TGA indicates that introduction of perturbation wave is conducive to enhance stability of droplet evolution and stability degree is directly related with wave number（ k）. However,stability tends to be deteriorated with increment of k. Compared with insoluble surfactant,evolution with soluble surfactant slows down slightly and stability is improved. Increasing of b,M,C,Ksstabilize the spreading,especially Marangoni effect and capillary force. Thickness of preset film has a primarily role on stability of droplet thickness evolution.