EAPSI: Pattern Formation on Liquid-Air Interfaces Due to Resonance

当两流体系统在垂直于流体界面的方向上振动时，流体界面上的图案会因共振而形成。这种现象被称为法拉第不稳定性。与日本宇宙航空研究开发机构（JAXA）的Satoshi Matsumoto博士合作的实验研究将使PI能够研究和验证通过使用电场在液-气界面上产生图案的理论计算。这次合作提供了独特的实验设备和世界一流的研究人员。该装置以前曾用于进行成功的初步试验。对界面模式生成的理解将导致许多工业相关工艺的进步，包括半导体晶体生长、微流体混合增强和石油开采技术。静电参数强迫为多流体系统中法拉第不稳定性的产生提供了一种独特的方法。通过非线性动力学的应用，研究人员将描述静电振荡产生这种不稳定性的潜在物理现象。在JAXA进行的实验将允许通过严格处理粘度的线性稳定性分析来验证多种流体和几何形状系统的稳定性阈值。该研究将补充传统的机械强迫法拉第不稳定性研究，为表面强迫的物理学提供额外的见解。这些知识将转化为对发生在界面对流、界面蒸发和凝固、电沉积等相变中的自激振荡的理解。控制表面力和整体力的尺度的分离将促进对整体力和表面力共同参与的其他不稳定现象的理解。该研究的直接应用包括增强微流体混合，更深入地了解液体晃动动力学，以及在使用水力压裂时提高石油采收率的潜力。NSF EAPSI奖是与日本科学促进会（JSPS）合作资助的。

When a stacked two fluid system is shaken in a direction perpendicular to the fluid interface, patterns on the fluid interface will develop as a result of resonance. This phenomenon is known as Faraday instability. Experimental research in collaboration with Dr. Satoshi Matsumoto at the Japanese Aerospace Exploration Agency (JAXA) will allow the PI to study and validate theoretical calculations for the development of patterns generated on a liquid-air interface through the use of electric fields. This collaboration offers access to both a unique experimental apparatus and a world-class research staff. The apparatus has been used previously to perform successful preliminary trials. The understanding of interfacial pattern generation will lead to advancements in a multitude of industrially relevant processes, including semiconductor crystal growth, microfluidic mixing enhancement, and oil recovery techniques.Electrostatic parametric forcing offers a unique approach to the generation of Faraday instability within multi-fluid systems. Through the application of nonlinear dynamics, researchers will delineate the underlying physics of this instability when generated via electrostatic oscillations. Experiments conducted in JAXA will allow for the validation of the stability thresholds for systems of multiple fluids and geometries obtained through a linear stability analysis that rigorously treats viscosity. The research will complement traditional studies on mechanically forced Faraday instability, offering additional insight into the physics of surface forcing. This knowledge will translate into the understanding of self-induced oscillations that occur in interfacial convection, interfacial evaporation, and phase transformations such as solidification and electrodeposition. The separation of the scales that govern surface forcing and bulk forcing will advance the understanding of other instability phenomena where both bulk and surface forces participate. Direct applications of the research include microfluidic mixing enhancement, a deeper understanding of liquid sloshing dynamics, and the potential for enhanced oil recovery when using hydraulic fracturing. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science (JSPS).