MSc Thesis project Spillway aerator flow & optimization – CFD studies

About the thesis

• The project is hosted by Vattenfall R&D.
• Thesis background/subject/assignment – A dam spillway is arguably the most critical structure for ensuring dam safety. It must discharge floodwaters without compromising its structural integrity, meaning the waterway must withstand the dynamic forces of flood flows. Even minor deficiencies can impair its ability to function properly. Nevertheless, damage can occur—sometimes unexpectedly—even under normal operating conditions and without exposure to extreme floods. Such deterioration may result from concrete cracking, evolving operational demands, or a combination of several factors.

To restore functionality when damages occur or prevent potential damage in an existing spillway, it is essential to introduce an appropriate countermeasure in the form of an aerator. The flow characteristics are however affected by the aerator layout and optimization is necessary. In terms of air supply, air pressure changes, air concentration etc, the project aims to evaluate the behaviors of modified aerator configurations.

• Thesis goal/purpose - The project aims to achieve the following goals.

(1) To simulate spillway flows and identify the basic flow features.

(2) To devise remedial measures to stop development of the damages or prevent potential damages to occur.

(3) To simulate two-phase air-water flow characteristics with the countermeasures.

(4) to examine/optimize aerator configurations and make comparisons.

• This assignment is for one student or two.

Execution

With an existing or hypothetical dam in the background, the study is executed with the help of CFD modeling in ANSYS FLUENT. Representative flow cases and potential aerator layouts are evaluated in the modeling. The geometrical and flood data are provided by the supervisor at Vattenfall R&D.

The student(s) will benefit from the project in several aspects.

• To get familiar with the ongoing work with dam safety and dam upgrade projects in the country
• To learn about hydraulic model tests
• To learn the fundamental knowledge of CFD
• To develop CFD skills for simulations of spillway flows
• To get acquainted with countermeasures against chute damages

The project consists of the following aspects.

1. Background and literature review
2. Data collection
3. Learning of CFD modeling techniques
4. Design of countermeasures
5. CFD simulations and result analyses
6. Report writing

Your profile

We are looking for a student to join our journey towards a fossil free future. You are soon to be graduated from your academic studies. You also identify yourself with our principles: active, open, positive and safe.

• Education - proper background is university education in civil (hydraulic) engineering, engineering physics or similar disciplines.
• Scope - the project corresponds to a 30 hp diploma work.
• Fluent written English
• Strong interests in hydropower, hydraulic engineering and dam safety.
• The time of execution should be within four (4) months, completed during 2026.

• Start of assignment – January 2026 or by agreement
• Location – Älvkarleby or by agreement
• Application – documents to be submitted include your official transcript of course records, CV and cover letter explaining your interest for hydropower. You should also have an examiner when you apply (specify the examiner’s contact info in the letter).
• Deadline – application deadline is 2025-10-31. However, applications are reviewed on a rolling basis, and the position may be filled as soon as a suitable candidate is found. Therefore, it's recommended not to wait until the deadline to apply—your opportunity may be gone by then.
• Contact person & supervisor at Vattenfall is James Yang (james.yang@vattenfall.com, phone 070-2723 200). Inquiry can be made by phone.

Diversity & inclusion - in everything we do

At Vattenfall we build on the fact that diverse teams can outperform homogeneous teams. But we can only unleash and leverage the power of diversity, if we make everybody feel included. Read more about our important work on diversity & inclusion https://careers.vattenfall.com/about-us/diversity-and-inclusion/

About Vattenfall

We have been electrifying industries, powering homes and transforming life through innovation and collaboration for more than 100 years. Empowered by our goal, we are determined to enable fossil free living within one generation. To succeed we, as one of Europe's leading energy companies, must be fossil-free ourselves. But that’s not enough. That’s why we are looking beyond our own industry, to see where we can really make a difference. Join us in our journey towards a fossil-free life within one generation.

Want to learn more about what we do? Visit www.vattenfall.com.

Since Vattenfall is a part of the Swedish critical infrastructure, many of our services are security classed. If this position is security classed the final candidates might be subjected to a security vetting process, according to the Swedish legislation.

Power Climate Smarter living - that’s our purpose. We are looking for the brightest students to make this happen. Together you will contribute to a fossil free future. You will have a unique position to contribute to our purpose. All we ask from you is to use your Superpowers and share your energy to help us achieve our goal.