Internship | Transient analysis of an air lift system for sea mining purposes

Deep sea mining is increasingly being considered as a resource of critical raw materials. The ores are taken from the seafloor and need to be lifted to the water surface over a height of several kilometers in a flexible pipeline, also known as a riser. There are two main lift methods: pumping and air lift. Although pumping is more energy efficient, maintenance of pumps at the sea floor is expensive and operation is difficult. In air-lift technology, air is compressed at the surface and injected several kilometers deep in the riser. The air reduces the hydrostatic pressure in the riser, leading to an upwards flow of water and air in the riser. This technique has a relatively low maintenance cost and easy system operability.

Several experimental and numerical studies have been conducted to assess the performance of air lift technology. However, these studies focus mainly on the steady state behaviour. Since many stability issues can occur in gas-liquid-solid flows, only solving the steady state flow behaviour is not sufficient to ensure safe operation of the system. In this project the aim is to assess the transient behaviour of an air lift system. The approach is to develop a transient 1D three phase flow simulator based on first principles. This simulator is then used to determine the stability of the air lift system and the performance of methods aimed to improve the operability of the air lift system.

We are looking for a student who is enthusiastic, critical and a team-player. We expect you to work hard and independently on your own project, but ask for help if needed. The student should regularly work from the office in Rijswijk in order to interact with supervisors and other colleagues. The student should have experience with both fluid dynamics and should be able to code in order to program the simulator.

You want an internship opportunity on the precursor of your career; an internship gives you an opportunity to take a good look at your prospective future employer. TNO goes a step further. It’s not just looking that interests us; you and your knowledge are essential to our innovation. That’s why we attach a great deal of value to your personal and professional development. You will, of course, be properly supervised during your work placement and be given the scope for you to get the best out of yourself. Furthermore, we provide:

• A highly professional, innovative internship environment, within a team of top experts.
• A suitable internship allowance (615 euro for wo-, hbo- and mbo-students, for a full-time internship).
• Possibility of eight hours of free leave per internship month (for a full-time internship).
• A free membership of Jong TNO, where you can meet other TNO professionals and join several activities, such as sports activities, (work-related) courses or the yearly ski-trip.
• Use of a laptop.
• An allowance for travel expenses in case you don’t receive an OV-card.

At TNO, we innovate for a healthier, safer and more sustainable life. And for a strong economy. Since 1932, we have been making knowledge and technology available for the common good. We find each other in wonder and ingenuity. We are driven to push boundaries. There is all the space and support for your talent and ambition. You work with people who will challenge you: who inspire you and want to learn from you. Our state-of-the-art facilities are there to realize your vision. What you do at TNO matters: impact makes the difference. Because with every innovation you contribute to tomorrow’s world. Read more about TNO as an employer.

At TNO we encourage an inclusive work environment, where you can be yourself. Whatever your story and whatever unique qualities you bring to the table. It is by combining our unique strengths and perspectives that we are able to develop innovations that make a real difference in society. Want to know more? Read what steps we are taking in the area of diversity and inclusion.

After the first CV selection, the application process will be conducted by the concerning department. TNO will provide a suitable internship agreement. If you have any questions about this vacancy, you can contact the contact person mentioned below.

Important to be aware of before applying:

• Before the start of the internship, the internship agreement from TNO needs to be signed. For students at a college or university based in the Netherlands, TNO uses the UNL-template (supplemented with a number of specific agreements from TNO). For students of foreign and MBO educational institutions, the TNO internship agreement applies. TNO does not sign any other internship agreements.
• Before the start of the internship, the educational institution will need to confirm in writing that:
  • 1) you are enrolled at the educational institution during the internship, and;
  • 2) the internship takes place as part of the programme of the study.
• The confirmation of educational institution takes place by signing the UNL template or forms prepared by TNO.
• Interns at TNO must be in possession of a Dutch residential address at the start of the internship. Performance of internship activities from abroad is not possible.