Numerical Modeling of High Resolution Electrohydrodynamic Jet Printing Using OpenFOAM

Electrohydrodynamic jet (e-jet) printing is a micro-/nano-scale additive manufacturing (AM) method that has emerged in recent years as a process to rival similar technologies such as inkjet printing. By utilizing electrostatic forces to induce fluid flow, e-jet has shown the ability to fabricate high resolution features with a wide variety of materials. Because it is a relatively new AM process, the printing behavior of many different types of inks are not completely understood, as existing knowledge of the process relies almost entirely on empirical methods that can be time intensive and difficult to implement for materials that are hazardous or not readily available. This paper discusses procedures for modeling both the electric and fluid dynamics of the e-jet printing process within OpenFOAM, an open-source computational fluid dynamics (CFD) solver. Further discussion has been provided to show simulations of the process at typical high resolution e-jet printing scales and to present existing limitations of the model.