The Turbulence and Vortex Dynamics (WDY) group at the Eindhoven University of Technology (The Netherlands, www.tue.nl/wdy) has two openings for PhD student positions on the physics of liquid jetting.

Background
In piezo-acoustic ink-jet print heads, a voltage pulse, applied to the piezoelectric element, induces a deformation of the print head channel creating a pressure wave in the ink, ultimately responsible for the ejection of ink droplets out of the nozzle [1]. Given the extreme accuracy achieved by modern inkjet printers, technological advancement requires a thorough physical understanding of the droplet generation mechanisms and of the subsequent droplet formation process. These two projects will investigate key physical aspects beyond the formation of inkjet droplets and the influence of physical effects that may interfere with this process. The projects will be conducted in close collaboration with Océ Technologies and in the framework of a larger network of PhD students investigating -with different techniques- several aspects at the basis of ink-jet printing technologies. 

Project description
The selected candidate(s) will perform numerical and theoretical research in order to investigate the fundamental physics beyond the dynamics of droplets formation in ink-jet print-heads. He/she will employ, extend and optimize existing numerical codes in order to perform high-fidelity, fully-3d numerical simulations of droplet jetting, will develop new codes to analyse the data produced, will develop novel, or improve upon existing, theoretical model also on the basis of the numerical investigations. The numerical methods that will be employed will include fully parallelized multiphase Lattice Boltzmann codes, developed in our group, with and without grid-refinement, as well as open-source codes based on volume of fluid method, like e.g. Gerris or Basilisk. The candidate will investigate full 3d effects, like the breaking of axial-symmetry during the jetting process. The candidate is expected to closely interact with Océ Technologies, as well as with other PhD students performing theoretical/experimental studies. 

References:
[1] Wijshoff, H. (2010). The dynamics of the piezo inkjet printhead operation. Physics Reports, 491(4), 77-177. doi.org/10.1063/1.4990082

We seek highly talented, enthusiastic, and exceptionally motivated candidates with an MSc. degree in Physics or engineering. The candidate must be able to demonstrate good programming skills, the drive and capacity to tackle different aspects of a complex problem with large independence, the capabilities to work in a team, strong communication skills, including fluency in written and spoken English.

When fulfilling a PhD position at the NWO Institutes Organisation (formerly FOM), you will get the status of junior scientist. You will have an employee status and can participate in all the employee benefits the NWO Institutes Organisation (NWO-I) offers. You will get a contract for four years. Your salary will be up to a maximum of 2,840 euro gross per month. The salary is supplemented with a holiday allowance of 8 percent and an end-of-year bonus of 8.33 percent. 
You are supposed to have a thesis finished at the end of your four year term with NWO-I. 
A training programme is part of the agreement. You and your supervisor will make up a plan for the additional education and supervising that you specifically need. This plan also defines which teaching activities you will be responsible (up to a maximum of ten percent of your time). The conditions of employment of NWO-I are laid down in the Collective Labour Agreement for Research Centres (Cao-Onderzoekinstellingen), more exclusive information is available at this website under Personeelsinformatie (in Dutch) or under Personnel (in English).