Thesis project - Application of roughness elements for effective energy

Company Description

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. 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 fossil freedom.

Job Description

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.

The project is to be performed at Vattenfall R&D.

Thesis background/subject/assignment

Compared with many other countries where high dams dominate, we have a large number of low- and medium-head facilities. With the revised design floods for many existing dams, the spilway chutes will experience higher discharges than before. This requires effective energy dissipation so that the river erosion downstream does not aggravate. To blast and excavate in an existing chute is never preferred. Instead, to introduce/add bed roughness elements is an efficient method to achieve this. This can be used separately or in combination with a stilling basin (energy dissipator).

The project deals with innovative chute roughness solutions for enhanced chute energy dissipation. By doing so, the flow impacts downstream are reduced at both low and high flood discharges.

Thesis goal/purpose

Based experimental data from Vattenfall R&D Älvkarleby, CFD mdeling is performed to evaluate chute roughness arrangements for enhanced hydraulic performance at high discharges and to mitigate downstream imapcts on river ecosystem even at low och medium spillway discharges. The project aims to achieve the following goals. (a) to get familiar with experimental procedure, roughness element design etc. (b) Through CFD modeling, to clarify turbulence flow structures and efficiency improvement at the roughness elements; (c) To enhance the understanding of chute spillway energy dissipation;

This assignment is for one student or two.

Execution

With an ongoing laboratory model in the background, the study is executed with the help of CFD modeling with ANSYS FLUENT. The previous model tests will be reviewed. Typical flow cases are simulated so as to map the turbulence flow structures and improvement in energy dissipation.

For the students

• To get familiar with the ongoing dam-safety projects in the country
• To learn about hydraulic model tests
• To learn the fundamental knowledge of CFD
• To develop CFD skills for modeling of chute spillway flows

The project consists of the following aspects.

1. Background and literature review
2. Data collection (spillway geometry and flows from laboratory)
3. Learning of CFD techniques
4. CFD model setup with experimental verification
5. CFD simulations, result analyses etc.
6. Report writing

Qualifications

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.
• Very good command of written English is required.
• Strong interests in hydropower, dam safety and hydraulic engineering.
• The time of execution should be within four (4) months, accomplished before the end of 2025.

Additional Information

More information

• Start of assignment – January 2025 or by agreement
• Location – Älvkarleby, Stockholm or by agreement
• Application – a combined document with your CV (with complete contact information) and cover letter, explaining your interest for hydropower. University grades are also to be submitted in the application.
• Deadline – the deadline for application is 2024-12-08. Incoming applications are processed on a running basis and the vacancy is filled as long a suitable candidate is found (the announce is then removed). This is the reason why you should not wait to the deadline to send in your application.
• Contact person and supervisor at Vattenfall – 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/