A simple linear model of piezo DoD inkjet print-head jetting output (drop speed, volume, momentum) provides an analytic prediction for the frequency response for steady state and initial printing streams from nozzles. The model has been applied to both existing commercial and development inkjet print-head devices.
Stephen D Hoath, "A Simple Model for DoD Inkjet Frequency Response" in Proc. IS&T Int'l Conf. on Digital Printing Technologies and Digital Fabrication (NIP31), 2015, pp 8 - 12, https://doi.org/10.2352/ISSN.2169-4451.2015.31.1.art00005_1