PhD position: Experimental analysis of boiling instabilities in advanced nuclear steam generators

cooled reactor or molten salt reactor offer certain advantages compared to traditional light water reactors. One such advantage is their potential to operate with a high thermal efficiency. This advantage stems from the fact that these reactors operate at much higher temperatures, enabling superheated steam generation. Traditional light water reactors utilize so-called U-tube steam generators in which saturated steam is produced. It is well known that such steam generators suffer from spontaneous oscillations of two-phase mass flow and pressure drop on the shell side. This phenomenon is well understood in light water reactors, allowing for safe and stable operation. However, these boiling instabilities are more severe in once-through helical steam generators, as the dryout point will shift rapidly up and down along the helical tubes. This oscillating behaviour can lead to thermal fatigue of the tube walls, which can ultimately result in mechanical failure. While this phenomenon is already complex enough in and of itself, it typically coincides with parallel channel instabilities. In this project, you will develop and build a laboratory steam generator set-up to study boiling instabilities in helical tubes. In the first year, you will help design and build the set-up along with a team of skilled technicians and an energetic supervisory team. Subsequently, you will study the characteristics of the boiling instabilities within the set-up and compare them to a numerical model. Your Working Environment You will join the Process & Energy (P&E) department at TU Delft's Mechanical Engineering faculty. Our department works along the themes of Energy, Flow and Processes. You will work together with top researchers highly skilled in thermodynamics, heat transfer, fluid mechanics. Moreover, we collaborate with researchers from the Reactor Institute Delft. You will have opportunities for professional development through both technical and non-technical courses. We expect that as part of your PhD you will take the lead on interacting and collaborating with other researchers at TU Delft, with research groups at other universities, and with industry and other stakeholders. Job requirements We are looking for a candidate with ample experience in experimental techniques and design of experiments involving physical transport phenomena. Furthermore, we expect that you have A MSc. degree in either chemistry, physics or mechanical engineering or similar field. Strong affinity with thermodynamics and transport equations. A keen interest in the nuclear industry and its future roles in society. An interest in transient modelling and analysis. Good communication skills and the ability to be a team player in a highly multidisciplinary setting. For this vacancy, a knowledge embargo exemption is required. Please check the following website: https://www.government.nl/themes/education/secondary-vocational-education-mbo-and-tertiary-higher-education/exemption-certain-engineering-or-nuclear-related-courses-of-study TU Delft (Delft University of Technology) Working at TU Delft means contributing to solutions that really make a difference. For over 180 years, we have been training engineers who make an impact worldwide in companies, government bodies, or as entrepreneurs. Our alumni turn knowledge into concrete solutions for the challenges of today and tomorrow. These challenges are changing rapidly. That is why we focus on themes such as energy, climate, digitalisation, artificial intelligence (AI), and smart mobility every day. Our education and research are directly aligned with what society needs now and in the future. At TU Delft, our people make the difference. With their knowledge and curiosity, our staff provide a high-quality education and conduct pioneering research that extends beyond the campus. You will have the opportunity to take the initiative, work with others, and grow as a professional. Working at TU Delft means join an international community of professionals and students. Together, we create knowledge, innovations, and solutions that help move the world forward. Faculty Mechanical Engineering From chip to ship. From machine to human being. From idea to solution. Driven by a deep-rooted desire to understand our environment and discover its underlying mechanisms, research and education at the ME faculty focusses on fundamental understanding, design, production including application and product improvement, materials, processes and (mechanical) systems. ME is a dynamic and innovative faculty with high-tech lab facilities and international reach. It's a large faculty but also versatile, so we can often make unique connections by combining different disciplines. This is reflected in ME's outstanding, state-of-the-art education, which trains students to become responsible and socially engaged engineers and scientists. We translate our knowledge and insights into solutions to societal issues, contributing to a sustainable society and to the development of prosperity and well-being. That is what unites us in pioneering research, inspiring education and (inter)national cooperation. Click here to go to the website of the Faculty of Mechanical Engineering. Do you want to experience working at our faculty? These videos will introduce you to some of our researchers and their work. Conditions of employment Doctoral candidates will be offered a 4-year period of employment in principle, but in the form of 2 employment contracts. An initial 1,5 year contract with an official go/no go progress assessment within 15 months. Followed by an additional contract for the remaining 2,5 years assuming everything goes well and performance requirements are met. Salary and benefits are in accordance with the Collective Labour Agreement for Dutch Universities, increasing from €3204 - €4051 gross per month, from the first year to the fourth year based on a fulltime contract (38 hours), plus 8% holiday allowance and an end-of-year bonus of 8.3%. As a PhD candidate you will be enrolled in the TU Delft Graduate School. The TU Delft Graduate School provides an inspiring research environment with an excellent team of supervisors, academic staff and a mentor. The Doctoral Education Programme is aimed at developing your transferable, discipline-related and research skills. The TU Delft offers a customisable compensation package, discounts on health insurance, and a monthly work costs contribution. Flexible work schedules can be arranged. Will you need to relocate to the Netherlands for this job? TU Delft is committed to make your move as smooth as possible! The HR unit, Coming to Delft Service , offers information on their website to help you prepare your relocation. In addition, Coming to Delft Service organises events to help you settle in the Netherlands, and expand your (social) network in Delft. A Dual Career Programme is available, to support your accompanying partner with their job search in the Netherlands. Additional information For more information about this vacancy, please contact dr. ir. Jurriaan Peeters (j.w.r.peeters@tudelft.nl). Application procedure Are you interested in this vacancy? Please apply no later than 15 November 2026 via the application button and upload the following documents: CV Motivational letter You can address your application to dr. ir. Jurriaan Peeters. Doing a PhD at TU Delft requires English proficiency at a certain level to ensure that the candidate is able to communicate and interact well, participate in English-taught Doctoral Education courses, and write scientific articles and a final thesis. For more details please check the Graduate Schools Admission Requirements. Please note: You can apply online. We will not process applications sent by email and/or post. As part of knowledge security, TU Delft conducts a risk assessment during the recruitment of personnel. We do this, among other things, to prevent the unwanted transfer of sensitive knowledge and technology. The assessment is based on information provided by the candidates themselves, such as their motivation letter and CV, and takes place at the final stages of the selection process.