A Simplified Numerical Procedure for the Characterization of an Ionic Liquid Meniscus With Evaporation

Abstract

Ionic liquid pure-ion electrospray propulsion may be a pivotal technology for micro-satellite propulsion. Extensive modeling is required to understand the underlying physical interactions. However, combining the coupled electric fields, transport mechanisms, and heating effects in a generalized numerical model remains challenging. An investigation conducted by Coffman allowed for insight into the dominant physical processes. This model was further refined, and a second implementation substantially improved computational performance and numerical stability. Unfortunately, these studies still struggled with the significant computational cost. Drawing from the results in Coffman’s previous work and integrating the later stability enhancements, the present work achieves a more robust and computationally efficient implementation. Here, the increased numerical stability of the revised model permits a larger range of parameter values to be used, and allows for data collection at practical capillary sizes, opening the door to experimental validation. Using the revised model, the thermodynamic properties of the ionic liquid are varied to explore the effect of diffusivity on the meniscus, which indicates increased numerical stability for liquids with higher diffusivity.