Numerical Simulation Engineer | Defense

At Capgemini Engineering, the world leader in engineering services, we bring together a global team of engineers, scientists, and architects to help the world’s most innovative companies unleash their potential. From autonomous cars to life-saving robots, our digital and software technology experts think outside the box as they provide unique R&D and engineering services across all industries. Join us for a career full of opportunities. Where you can make a difference. Where no two days are the same. YOUR ROLE As a Numerical Simulation Engineer, you will play a central role in the modelling, simulation, and analysis of complex physical phenomena for critical defence and aerospace applications, working closely with R&D, design, and production teams to ensure the performance and reliability of cutting-edge solutions. In this role you will play a key role in:
• Modelling and analysing fluid flows (compressible/incompressible, turbulent, multiphase) for critical applications including aerodynamics, propulsion, and thermal management, using industry-standard tools such as OpenFOAM, ANSYS Fluent/CFX, STAR-CCM+, or in-house codes, and validating results through comparison with experimental or analytical data
• Coupling physical phenomena such as fluid-structure interaction, thermal-mechanical, and aeroacoustics using tools like ANSYS Multiphysics, COMSOL, or internal codes, and performing finite element analysis (FEM) to assess structural integrity, stress, deformation, and fatigue in mechanical components interacting with fluid flows
• Developing reduced-order models (ROM) or hybrid methods to optimise system performance, and using ANSYS Mechanical, Creo Simulate, or similar tools for static and dynamic structural analyses
• Contributing to the improvement of simulation tools through automation and Python scripting, leveraging High-Performance Computing (HPC) environments, and collaborating with data science teams to integrate AI/ML approaches into simulation workflows
• Proposing innovative solutions to address technical challenges such as drag reduction and thermal management, and supporting wind tunnel or laboratory tests to correlate simulation and experimental data
• Working closely with R&D, design, testing, and customer teams, preparing technical reports, presentations, and specifications for project reviews, and contributing to a culture of scientific rigour and continuous innovation

YOUR PROFILE
• You hold a Master's or Engineering Degree in Fluid Mechanics, Aeronautics, Aerospace Engineering, Mechanical Engineering, or Applied Physics, and bring 3 to 5 years of experience in numerical simulation with a CFD focus, in an industrial or academic environment (internships included)
• You are proficient in at least one CFD software (OpenFOAM, ANSYS Fluent/CFX, or STAR-CCM+), with solid knowledge of turbulence models (RANS, LES, DES), numerical methods (FVM, FEM), and meshing tools (ICEM CFD, Pointwise, snappyHexMesh)
• You have experience or strong interest in multi-physics and FEM, including fluid-structure interaction (FSI), thermal-mechanical coupling, and solid mechanics, with familiarity with tools such as ANSYS Multiphysics or COMSOL
• You are comfortable with scripting and automation (Python, Bash) for pre/post-processing, and have knowledge of High-Performance Computing (HPC) and Linux/cluster environments; experience with CAD software (CATIA, SolidWorks, Creo) and version control tools (Git, SVN) is a plus
• French proficiency and a minimum B2 level of English are required for this role What you'll love about working here:
• Dedicated Innovation Labs – We help the world's largest innovators engineer the products and services of tomorrow by leveraging our experts and labs, dedicated to topics such as 5G, 6G, AI, Autonomous Vehicles, and Quantum. As a Numerical Simulation Engineer, you will be at the forefront of technological innovation in defence and aerospace.
• Digital Campuses and Academy – Our engineering academy offers more than 60,000 hours of training, alongside our digital campus covering GenAI, data, and sustainability. Whether you're looking to deepen your expertise in CFD tools or explore AI/ML integration in simulation workflows, we support your learning journey at every step.
• Environmental Sustainability – Our teams around the world pave the way for a sustainable future, from building electric and hydrogen cars to solar airships and advanced thermal management solutions. Join us and contribute to projects that truly make a difference for our planet.
• Hybrid Working – We encourage flexibility when it comes to when and where work gets done. Employees work with their managers to determine an arrangement that works best for their role and personal circumstances. Capgemini is a global business and technology transformation partner, helping organizations to accelerate their dual transition to a digital and sustainable world, while creating tangible impact for enterprises and society. It is a responsible and diverse group of 340,000 team members in more than 50 countries. With its strong over 55-year heritage, Capgemini is trusted by its clients to unlock the value of technology to address the entire breadth of their business needs. It delivers end-to-end services and solutions leveraging strengths from strategy and design to engineering, all fuelled by its market leading capabilities in AI, cloud and data, combined with its deep industry expertise and partner ecosystem. The Group reported 2023 global revenues of €22.5 billion.