Your responsibilities

The Engineering Department (EN) provides CERN with the engineering competences, infrastructure systems and technical coordination required for the design, installation, operation, maintenance and dismantling phases of the CERN accelerator complex and its experimental facilities. The mandate of the Cooling and Ventilation (CV) group is to carry out the engineering studies, operation and maintenance of the cooling systems, pumping stations, air conditioning installations and fluid distribution systems for the accelerator complex including their experimental areas and special cooling systems of the particle detectors. It also provides service to the CERN Control Centre and Computer Centre among other installations.

You will be part of Computational Fluid Dynamics (CFD) team within the Project Section (PJ) of the Cooling and Ventilation (CV) group where you will collaborate with other CFD engineer and project engineers to support. The aim of the CFD studies is to increase operational efficiency, lower design and engineering costs, and accelerate development of new equipment for particle physics. This is achieved finding numerical solution of thermal and fluid dynamics problems for particle detectors, accelerators, underground caverns, experimental buildings, etc. The mandate of this team is to provide assistance to the LHC Experiments and Machine in the design and prototype phase and support CERN projects. The numerical tools used are ANSYS-Fluent and Flownex.

You will take on the following responsibilities:

• Prepare and simplify the geometrical model for simulations.
• Collect the simulation inputs from all different stakeholders and prepare the study case matrix.
• Create the mesh, check and improve its quality and apply boundary conditions.
• Prepare case files (steady state and transient analysis) for High Performance Computing (HPC) cluster solving.
• Assess the results quality and accuracy, extract and visualise data in multiple format (contour plots, graphs, videos).
• Prepare and write technical reports to document the results the results in dedicated technical reports.
• Carry out sensitivity studies on different parameters (mesh invariance, multiple scenarios, etc.).
• Provide support to junior engineers and technical students.

You will benefit from:

• The opportunity to broaden your knowledge and experience into new areas like fluid dynamics, cooling and system installation and commissioning.
• Specific training and support for professional development to foster your skills and develop your talents.

Your profile

Skills:

• Experience:
• Demonstrated experience of Computational Fluid Dynamics software (Ansys Fluent, Fluent Meshing, SpaceClaim, OpenFoam, etc).
• Demonstrated experience with programming/scripting (e.g. MATLAB, Python, or C++).
• Experience with cluster computations.
• Experience working with both new and past simulations/studies.
• Knowledge:
• Good knowledge of fluid dynamics, thermodynamics, fluid and thermal analysis.
• Good knowledge of HPC.
• Spoken and written English or French, with a commitment to learn the other language.

Eligibility criteria:

• You are a national of a CERN Member or Associate Member State.
• By the application deadline, you have a maximum of two years of professional experience since graduation in Mechanical Engineering (or a related field) and your highest educational qualification is either a Bachelor's or Master's degree.
• You have never had a CERN fellow or graduate contract before.
• Applicants without University degree are not eligible.
• Applicants with a PhD are not eligible.

Additional Information

Job closing date: 04.08.2025 at 23:59 CEST.

Contract duration: 24 months, with a possible extension up to 36 months maximum.

Target start date: 01-October-2025

This position involves:

• Work in Radiation Areas.
• Interventions in underground installations.
• A valid driving licence.

Job reference: EN-CV-PJ-2025-129-GRAE

Field of work: Mechanical Engineering

What we offer

• A monthly stipend ranging between 5196 and 5716 Swiss Francs (net of tax).
• Coverage by CERN's comprehensive health scheme (for yourself, your spouse and children), and membership of the CERN Pension Fund.
• Depending on your individual circumstances: installation grant; family, child and infant allowances; payment of travel expenses at the beginning and end of contract.
• 30 days of paid leave per year.
• On-the-job and formal training at CERN as well as in-house language courses for English and/or French.

About us

At CERN, the European Organization for Nuclear Research, physicists and engineers are probing the fundamental structure of the universe. Using the world's largest and most complex scientific instruments, they study the basic constituents of matter - fundamental particles that are made to collide together at close to the speed of light. The process gives physicists clues about how particles interact, and provides insights into the fundamental laws of nature. Find out more on http://home.cern.

Diversity has been an integral part of CERN's mission since its foundation and is an established value of the Organization. Employing a diverse workforce is central to our success.