PhD in Printing of Complex Fluids

Do you have a passion for understanding complex, multicomponent fluid flows at the microscale and at very high speeds? Are you driven by the challenge of pushing technology innovation to the next level? This PhD position might be for you! 

This project will explore how multicomponent fluids flows in droplets just after being created during the process of inkjet printing using piezoactuation. Inkjet printing has moved beyond printing graphics on paper, and its applicability has been demonstrated for numerous applications such as contact lenses, dental implants, electronic circuit boards, solar panels, 3D rapid prototypes, and even for printing of DNA and protein substances. These new applications demand the utmost in terms of reliability, as an imprecise deposition of even a single droplet can render the printed application useless, e.g. circuit failures in printed electronics. The state-of-the-art applications require inkjet printing to generate as small as possible droplets (few microns in size) of highly complex fluids at the highest possible rates (10000 droplets per second), while also maintaining constant droplet volumes and impact velocities (of several meters per second).

Previous studies have revealed that solid impurities in the ink can cause bubble entrainment causing cavitation or by directly interacting with the oscillating meniscus. Ultra high-speed experimental imaging and corresponding highly resolved numerical simulations have shown that this vorticity field in the fluid arises due to the misalignment of the density and pressure gradients at the liquid-air interface within the nozzle, resulting in meniscus distortions and bubble pinch-off, yielding what are known as satellite droplets. These unwanted droplets can cause direct failure or loss of performance of the final printed features. As inks increase in complexity due to multiple components, and additionally as ink solid fraction, e.g. pigments, increase, the likelihood of these impurities forming increases dramatically. 

The aim of this PhD project is to gain an in-depth quantitative understanding of the physicochemical hydrodynamics governing the jetting behavior of a complex multicomponent fluid, i.e. a fluid containing multiple miscible liquids, surfactants, polymers, and colloidal pigment particles just after droplet creation.

Your duties and responsibilities include: 

• develop your own experimental tools to investigate these problems at high speeds;
• create model ink systems containing multiple components similar to but reduced in complexity to industrial inks;
• explain and communicate your findings to both academic and industrial collaborators;
• working with a larger team of researchers to investigate this interdisciplinary challenge.

You will work here

The research is embedded within the chair group of Physical Chemistry and Soft Matter Physical Chemistry and Soft Matter | WUR, which is led by Prof. Jasper van der Gucht. You will be part of the Physics of Soft Matter team PhySM - Physics of Soft Matter, where you will be co-supervised primarily by dr. Uddalok Sen and supported by dr. Thomas Kodger. During your PhD, you will directly collaborate with a postdoctoral researcher yet to be hired. 

You have a passion for understanding fundamental physical processes related to dispersions and fluid flow especially at high speeds. You also have a passion for developing, designing and building your own models and instrumentation to answer key scientific questions. You also have the flexibility to work in a team within a well-equipped laboratory and communicate results to experts in different, but related fields.

You also possess: 

• a successfully completed MSc degree in physics, physical chemistry, fluid dynamics, or soft matter;
• the ability to work independently;
• a strong desire to work with new instrumentation;
• experience with soft materials and computational tools;
• experience with microscopy, in particular with high speed imaging.

For this position your command of the English language is expected to be at C1 level. Sometimes it is necessary to submit an internationally recognised Certificate of Proficiency in the English Language. More information can be found here.

Wageningen University & Research offers excellent terms of employment. A few highlights from our Collective Labour Agreement include:

• partially paid parental leave;
• working hours that can be discussed and arranged so that they allow for the best possible work-life balance;
• there is a strong focus on vitality and you can make use of the sports facilities available on campus for a small fee;
• a fixed year-end bonus of 8.3%;
• excellent pension scheme.

In addition to these first-rate employee benefits, you will receive a fully funded PhD position and you will be offered a course program tailored to your needs and the research team.
The gross salary for the first year is € 3.059.- per month rising to € 3.881.- in the fourth year in according to the Collective Labour Agreements for Dutch Universities (CAO-NU) (scale P). This is based on a full-time working week of 38 hours. We offer a temporary contract for 18 months which will be extended for the duration of the project if you perform well. 

We encourage development and internal mobility within our organisation. Our recruitment and selection policy sets out the conditions that apply specifically to you as a (former) employee. If you have any questions, we are happy to help.

You will work on the greenest and most innovative campus in the Netherlands, in an international and open working environment. 

Wageningen University & Research is the university and research centre for life sciences. The themes we deal with are relevant to everyone around the world and Wageningen, therefore, has a large international community and a lot to offer to international employees. 

Because we expect you to work and live in the Netherlands our team of advisors on Dutch immigration procedures will help you with the visa application procedures for yourself and, if applicable, for your family. 

Feeling welcome also has everything to do with being well informed. Wageningen University & Research's International Community page contains practical information about what we can do to support international employees coming to Wageningen. Furthermore, our Welcome Center can assist you with any additional advice and information about for example housing, opening a bank account, dual career programs or schooling. Finally, certain categories of international staff may be eligible for a tax exemption on a part of their salary during the first five years in the Netherlands.

For more information about the position, please contact Uddalok Sen, Assistant Professor via email: Uddalok.sen@wur.nl.

Questions about the procedure? Get in touch with Evelien Janssen, Corporate Recruiter, via email: evelien.janssen@wur.nl.

Ready to apply?
You can apply directly using the apply button on the vacancy page on our website which will allow us to process your personal information with your approval. Only applications submitted through our website will be considered.

To apply, please send the following documents (max. 2 pages in total for both documents):

• Complete and up-to-date curriculum vitae;
• motivation letter.

The maximum length of the documents must not exceed 3 pages. If it exceeds, applications will not be considered. Additional files such as grades and transcripts are not required during this stage and will not be considered.

You can apply up to and including 15 May 2026. The first interviews are scheduled for May 25, 2026.

Welcome, safe, and valued
Wageningen University & Research (WUR) highly values diversity and inclusion because we believe that different insights lead to innovative solutions. We create a work environment where everyone feels welcome, safe, and appreciated, regardless of background, identity, or experience. Together, we are building a culture where everyone's unique contribution adds to the success of our organization.

​The mission of Wageningen University & Research is “To explore the potential of nature to improve the quality of life”. Under the banner Wageningen University & Research, Wageningen University and the specialised research institutes of the Wageningen Research Foundation have joined forces in contributing to finding solutions to important questions in the domain of healthy food and living environment. With its roughly 30 branches, 7,600 employees (6,700 fte) and 13,100 students and over 150,000 participants to WUR’s Life Long Learning, Wageningen University & Research is one of the leading organisations in its domain. The unique Wageningen approach lies in its integrated approach to issues and the collaboration between different disciplines.

Read the 5 reasons why your future colleagues enjoy working at WUR and watch the video below to get an idea of our green campus!

We will recruit for the vacancy ourselves, so no employment agencies please. However, sharing in your network is appreciated.

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