The subsurface plays a critical role in tackling the challenges of a changing climate. It provides drinking water amidst increasingly frequent droughts, and it is a keystone of the energy transition by providing geothermal energy and storage space for hydrogen. Despite its importance, our insights into the subsurface's properties and processes are scarce, limiting our ability to fully characterize this environment. The resulting uncertainties require careful analysis to inform societally responsible subsurface operations: How can we sustainably heat as many homes as possible? Where shall we establish the next hydrogen storage reservoir? What can we do to mitigate our operation's environmental and economic risks?

To answer such questions, data assimilation systematically combines numerical models with data to explore different possibilities of what the true system could be like, but its implementation remains a challenge in complex systems. Most data assimilation methods either over-simplify or are prohibitively inefficient, which compromises our decision-making. In this project, you will join a collaboration between TU Delft and the Norwegian energy company Equinor to co-develop an improved data assimilation strategy that uses a statistical method related to normalizing flows and diffusion models. This method can exploit advanced information about the numerical model, such as which variables are indirectly related to each other (conditional independence) or degrees of nonlinearity (How complex do we have to make our updates?). This allows us to create a powerful data assimilation framework that is always as simple as possible and as complex as necessary, which yields improved subsurface characterizations that will enable better, more reliable decision making.

As a PhD student at TU Delft, you will:

• Familiarize yourself with the methodological foundations of triangular measure transport and data assimilation
• Co-develop a scalable, adaptive, nonlinear data assimilation method based on triangular transport
• Explore innovative strategies to adapt the method to different environmental systems
• Apply the resulting algorithm to analyse the properties and uncertainties of a real geothermal operation

This four-year project is part of a collaboration between TU Delft and DA research at Equinor in Bergen, Norway. You will join the reservoir engineering section at TU Delft’s Department of Geoscience & Engineering, where you will find a vibrant and collaborative environment in which you will have the opportunity to interact with experts in data assimilation, geothermal energy, and numerical simulation. You will be encouraged to learn new skills and develop your own ideas, and you will share your findings at conferences and in peer-reviewed journals. These experiences will pave the way for diverse career paths in industry, consultancy, governmental agencies, or academia.

• You hold a Masters degree in geoscience, geophysics, applied mathematics/statistics, or a similar field
• You thrive on systematic, code-based research, and have an aptitude for abstract or mathematical thinking.
• You have a keen interest in data assimilation and machine learning, and are excited to explore their applications in complex environmental systems
• You have experience with Python or a similar programming language. Experience with computationally intensive numerical methods is a plus.
• You are a highly motivated and self-driven researcher, capable of working both independently and as part of a team
• You have an excellent command of written and spoken English

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.

Fixed-term contract: 4 years.

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 € 2770 per month in the first year to € 3539 in the fourth year. 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. 

For international applicants, TU Delft has the Coming to Delft Service. This service provides information for new international employees to help you prepare the relocation and to settle in the Netherlands. The Coming to Delft Service offers a Dual Career Programme for partners and they organise events to expand your (social) network.

Delft University of Technology

Delft University of Technology is built on strong foundations. As creators of the world-famous Dutch waterworks and pioneers in biotech, TU Delft is a top international university combining science, engineering and design. It delivers world class results in education, research and innovation to address challenges in the areas of energy, climate, mobility, health and digital society. For generations, our engineers have proven to be entrepreneurial problem-solvers, both in business and in a social context.

At TU Delft we embrace diversity as one of our core values and we actively engage to be a university where you feel at home and can flourish. We value different perspectives and qualities. We believe this makes our work more innovative, the TU Delft community more vibrant and the world more just. Together, we imagine, invent and create solutions using technology to have a positive impact on a global scale. That is why we invite you to apply. Your application will receive fair consideration.

Challenge. Change. Impact!

Faculty Civil Engineering & Geosciences

The Faculty of Civil Engineering & Geosciences (CEG) is committed to outstanding international research and education in the field of civil engineering, applied earth sciences, traffic and transport, water technology, and delta technology. Our research feeds into our educational programmes and covers societal challenges such as climate change, energy transition, resource availability, urbanisation and clean water. Our research projects are conducted in close cooperation with a wide range of research institutions. CEG is convinced of the importance of open science and supports its scientists in integrating open science in their research practice. The Faculty of CEG comprises 28 research groups in the following seven departments: Materials Mechanics Management & Design, Engineering Structures, Geoscience and Engineering, Geoscience and Remote Sensing, Transport & Planning, Hydraulic Engineering and Water Management.

Click here to go to the website of the Faculty of Civil Engineering & Geosciences.