Abstract The dynamic interaction of a fluid particle with a continuous phase has been often a topic of study, for its broad range of applications in various industries. Better understanding of particle-fluid interface instability can assist to enhance the efficiency of different processes and possibly avoid unfavorable consequences. In the present work, a weakly nonlinear instability analysis is performed to study the driven shape oscillations of a fluid particle (droplet or bubble) immersed in another fluid (liquid or gas). The analysis is conducted using a perturbation expansion approach, allowing for shape mode interactions for any arbitrary number of modes. The present work intends to provide an analytical solution to forced shape oscillations of a fluid particle, which accounts for viscosity of both fluids involved, instability nonlinearities, and shape mode interactions. The model proposed is used to study the effect of various parameters on the deformation of fluid particle interface. The cases studied provide an insight into shape mode interactions and resonances due to nonlinearity. Moreover, the results show that the viscosity of the fluid particle can play a role in increasing the chances of greater mode interaction and parametric resonance effects, especially for relatively large initial deformations.

中文翻译：

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DD论流体粒子界面和形状振荡的不稳定性

摘要 流体颗粒与连续相的动态相互作用经常成为研究的主题，因为它在各个行业中有着广泛的应用。更好地了解粒子-流体界面不稳定性有助于提高不同过程的效率，并可能避免不利后果。在目前的工作中，执行弱非线性不稳定性分析来研究浸入另一种流体（液体或气体）中的流体粒子（液滴或气泡）的驱动形状振荡。该分析是使用扰动扩展方法进行的，允许对任意数量的模式进行形状模式交互。目前的工作旨在为流体粒子的受迫形状振荡提供一个解析解，它解释了所涉及的两种流体的粘度、不稳定性非线性、和形状模式相互作用。所提出的模型用于研究各种参数对流体颗粒界面变形的影响。所研究的案例提供了对由于非线性而导致的形状模式相互作用和共振的深入了解。此外，结果表明流体颗粒的粘度可以在增加更大模式相互作用和参数共振效应的机会方面发挥作用，特别是对于相对较大的初始变形。