PhD position in charge transport and streaming electrification at the oil–cellulose interface Full-time

PhD Position In Charge Transport And Streaming Electrification At The Oil–Cellulose Interface

Uppsala University, Department of Electrical Engineering

Electrification and digitalisation are among the largest areas for the future in the conversion to sustainable societies. The Department of Electrical Engineering conducts successful research and education in the areas – renewable energy sources, electric vehicles, industrial IoT, 6G communication and wireless sensor networks as well as research and education within Life Science, smart electronic sensors and medical systems. The Department of Electrical Engineering is an international workplace with around 170 employees that all contribute to important technical energy and health solutions at the Ångström Laboratory.

Come and work with us! The position will be at the Division of Network Embedded Systems, at the Department of Electrical Engineering. Here you will find a friendly work environment with a lively doctoral network and a variety of experimental projects. The Division works in collaboration with Swedish companies – public and private – and stakeholders in the different fields of research. We look forward to receiving your application. Join us and build the future with us!

Read more about our benefits and what it is like to work at Uppsala University.

Project Description

Power transformers are the backbone of modern electrical grids, and their reliability is essential for a stable energy supply. A key component of the insulation system is transformer oil. Between the windings a high oil flow is desired to improve cooling performance, on the other side the velocity has to be limited to provide failures due to streaming electrification, which means the accumulation of static charge due to oil flow. There are simple models to describe the phenomenon, however, the underlying physics remains largely unresolved. Because direct measurements inside an operating transformer are impossible, the field urgently needs new laboratory methods and a modern theoretical framework to understand how charge is generated, transported, and released in these systems.

This PhD project offers the opportunity to work at the intersection of fluid mechanics, electrochemistry, and soft-matter physics, addressing a problem with both deep scientific challenges and major industrial relevance. Classical models such as the Helmholtz–Smoluchowski equation fail for transformer oils because of their extremely high resistivity, the significant surface conductivity of cellulose, possible electroviscous effects, and the penetration of oil into the porous solid. These factors create a rich, unexplored physical landscape where new insights are waiting to be discovered.

The goal of the project is to develop a predictive model for streaming electrification supported by precision laboratory experiments. You will design experimental setups, measure streaming currents under controlled conditions, and build theoretical tools that capture the complex electrohydrodynamics at the oil–cellulose interface. The outcome will be a framework with a small set of governing parameters that can be used to assess and mitigate electrification risks in real transformers.

The project, funded by Hitachi Energy AB, will be conducted in close collaboration with the industrial partner and their research organization. Access to state-of-the-art facilities and expertise is ensured, though special rules may apply regarding publication and IP rights.

We have an exciting work environment designed by the doctoral student and the research team together. The doctoral student will be supervised by at least two supervisors. The Department of Electrical Engineering also gives a salary supplement to employed PhD students at the Department of Electrical.

Duties

PhD studies require independent research work within a chosen subject, supported by supervisors and collaboration with fellow researchers.

Research tasks include:

• Developing a dedicated experimental setup to measure streaming currents in transformer oils under well-controlled laminar-flow conditions.
• Quantifying streaming currents generated by different transformer oils flowing through cellulose ducts, enabling systematic comparison across materials and operating parameters.
• Building advanced theoretical models that describe the electrohydrodynamics at the oil–cellulose interface, capturing charge generation, transport, and electric double-layer behavior.
• Contributing to teaching and departmental activities, up to a maximum of 20% of the total working time, as part of the doctoral training.

Training in relevant techniques is provided as part of the doctoral education.

Qualifications Required

To meet the entry requirements for doctoral studies, you must

• hold a Master's (second-cycle) degree in physics, engineering physics or material science, or
• have completed at least 240 credits in higher education with at least 60 credits at Master's level including an independent project worth at least 15 credits, or
• have acquired substantially equivalent knowledge in some other way.

Great emphasis will be placed on personal suitability. The successful candidate should have strong collaborative skills and the ability to work both independently and as part of a team.

Excellent communication skills in English, both written and spoken, are required.

Qualifications Desired

Previous experience in working with cellulose or electrical measurement systems will be valuable.

About The Employment

Fixed term position 48 months, in accordance with Chapter 5, Section 7 of the Higher Education Ordinance. Full-time. Start date 2026-09-01 or as agreed. Location: Uppsala.

Rules governing doctoral students are set out in the Higher Education Ordinance Chapter 5, Sections 1-7 and in Uppsala University's rules and guidelines.

Application: Please use the link below. You should include a brief description of your research interests and relevant experience, a CV, copies of diplomas and certificates, thesis (or a draft thereof) and other relevant documents. You are encouraged to provide contact information to reference.

Information about the employment is provided by: Associate Prof. Apurba Dev; tel: +46 18-471 10 77; e-mail: apurba.dev@anagstrom.uu.se.

Welcome with your application no later than July 1, 2026. UFV-PA 2026/1886.

Uppsala University is a broad research university with a strong international position. The ultimate goal is to conduct education and research of the highest quality and relevance to make a difference in society. Our most important asset is all of our 7,600 employees and 53,000 students who, with curiosity and commitment, make Uppsala University one of Sweden's most exciting workplaces.

Read more about our benefits and what it is like to work at Uppsala University https://uu.se/om-uu/jobba-hos-oss/

The position may be subject to security vetting. If security vetting is conducted, the applicant must pass the vetting process to be eligible for employment.

Please do not send offers of recruitment or advertising services.

Submit your application through Uppsala University's recruitment system.

Type of employment – Temporary position

Contract type – Full time

First day of employment – 2026-09-01 eller enligt överenskommelse

Number of positions – 1

Full-time equivalent – 100

City – Uppsala

County – Uppsala län

Country – Sweden

Reference number – UFV-PA 2026/1886

Published – 01.Jun.2026

Last application date – 01.Jul.2026