Development of limited-view and three-dimensional reconstruction method for analysis of electrohydrodynamic jetting behavior

For an electrohydrodynamic (EHD) jet, variables such as the direction of the meniscus and the ejection stability need to be analyzed. Thus, the EHD jet should be observed three-dimensionally (3D) because the variables can only be obtained in the 3D field, especially in unstable modes. However, if the 3D field is reconstructed from multi-directional binary images, eliminating reconstruction errors caused by invisible areas is almost impossible, even when using a tomographic technique. To solve this problem, a new 3D reconstruction method including an ellipse estimation was developed in this study. The method was verified by numerical simulation and applied to estimate the jetting flow rate and the direction of an ethanol droplet ejected from a nozzle according to a voltage.