Electrical manipulation of jets, drops and liquid marbles

Abstract

Jets and drops are ubiquitous in everyday life, and can be found in applications ranging from personal care products to printing. As the precision required in jet- and drop-based applications increases, the degree of control over their properties, such as size and shape, also needs to be increased accordingly. Generation and actuation of jets and drops are commonly done pneumatically and hydrodynamically; new ways to control them may lead to overcoming of the limits in generation rates and precision of their control. Electrical manipulation of liquid structures have long been demonstrated for forming nanometer-scaled liquid jets and drops in techniques known as electrospinning and electrospraying respectively. Despite these proven techniques, the parameter space under which electrically charged jets and drops operate remains inadequately understood. In this talk, we will discuss new dynamics of electrically charged jets observed experimentally, including jet coiling and drop kissing. We will then show our efforts in utilizing these dynamics in printing and in evaluation of emulsion stability. If time allows, I will also introduce the electrical manipulation of particle-coated millimetered drops, which are called liquid marbles, and its application as a versatile platform for controlling liquid-marble reactors that may find use in chemical synthesis and diagnostics.