CFD/Thermal Simulation Engineer in Lille

Amazon Web Services is seeking a CFD/Thermal Simulation Engineer to develop thermal and CFD models to predict, optimize and validate the thermal performance of the 5–10 MW SST.

As a CFD/Thermal Simulation Engineer you will build 3D CFD (Icepak / Fluent / COMSOL / Simcenter) and thermal-resistance models predicting SST thermal performance on a defined project.

You will handle conjugate heat transfer, mesh/fidelity trade-offs, hotspot prediction and junction-margin analysis under variable load and correlate to measurement and feed optimized designs to thermal/mechanical and PE teams.

Key job responsibilities

• CFD modeling

• Build 3D thermal simulations using Icepak, ANSYS Fluent, COMSOL, Simcenter or equivalent tools.
• Model heat transfer through power electronics, cooling interfaces and system assemblies.
• Evaluate thermal distribution, hotspots and cooling-system performance.

• Thermal modeling

• Develop thermal-resistance models and junction-to-coolant analyses.
• Support semiconductor and component thermal-margin definition.
• Analyze thermal behavior under variable load profiles.

• Correlation & optimization

• Correlate simulation results with experimental measurements.
• Use test results to refine models and identify design improvements.
• Support thermal design optimization with Mechanical and Power Electronics teams.

• SST System Alignment

• Model system environmental conditions and thermal derating, including -30°C to 40°C ambient and above-40°C derating requirements.
• Correlate thermal models with efficiency, load-profile and qualification data across the SST operating envelope.
• A day in the life

As a CFD/Thermal Simulation Engineer, you'll focus on building sophisticated 3D thermal simulations that predict how heat flows through power electronics and cooling systems.

Your day might include developing conjugate heat transfer models using tools like Icepak, ANSYS Fluent, COMSOL, or Simcenter, then correlating your simulation results with real laboratory measurements to refine designs.

You'll collaborate with mechanical and power electronics teams to identify hotspots, analyze thermal behavior under different operating conditions, and translate your findings into actionable design improvements.

You'll also work across variable environmental conditions—from extreme cold to high ambient temperatures—ensuring systems perform reliably throughout their operating envelope.

About the team

We are AWS Infrastructure Services, the team that keeps the cloud running.

We design, plan, deliver, and operate all AWS global infrastructure—the servers, storage, networking, power, and cooling equipment that enable our customers' success.

Our team tackles some of the most complex thermal and infrastructure challenges in the industry, where thousands of variables impact performance and reliability.

We're building a collaborative environment where you'll partner with talented engineers across disciplines, contribute to full product ownership from concept to deployment, and help shape the future of how we cool and power the world's cloud infrastructure.

You'll be part of a group that values continuous learning, embraces diverse perspectives, and supports your growth as you solve problems that matter at scale.

Why AWS?

Amazon Web Services (AWS) is the world’s most comprehensive and broadly adopted cloud platform.

We pioneered cloud computing and never stopped innovating — that’s why customers from the most successful startups to Global 500 companies trust our robust suite of products and services to power their businesses.

Inclusive Team Culture

Here at AWS, it’s in our nature to learn and be curious.

Our employee-led affinity groups foster a culture of inclusion that empowers us to celebrate our differences.

Ongoing events and learning experiences, including our Conversations on Race and Ethnicity (CORE) and diversity conferences, inspire us to never stop embracing our uniqueness.

Work/Life Balance

We value work-life harmony.

Achieving success at work should never come at the expense of sacrifices at home, which is why flexible work hours and arrangements are part of our culture.

When we feel supported in the workplace and at home, there’s nothing we can’t achieve in the cloud.

Mentorship & Career Growth

We have a career path for you no matter what stage you’re in when you start here.

We’re continuously raising our performance bar as we strive to become Earth’s Best Employer.

That’s why you’ll find endless knowledge-sharing, mentorship and other career-advancing resources here to help you develop into a better-rounded professional.

• Basic Qualifications
• Bachelor's degree in Electrical Engineering.
• Demonstrated understanding of power-electronics thermal behavior.
• Experience and ability to correlate models with laboratory measurements.
• Experience documenting design decisions, assumptions, trade-offs, risks and technical specifications.
• Experience using engineering analysis and measured evidence to drive decisions.
• Preferred Qualifications
• Master's degree or Ph D in Electrical Engineering.
• 2+ years experience in CFD/thermal simulation for electronics cooling with measured correlation.
• Experience with Icepak, ANSYS Fluent, COMSOL or Simcenter.
• Demonstrated working effectively with adjacent engineering disciplines and contribute to full A-to-Z product ownership.
• Demonstrated operating effectively in a greenfield environment where standards and reference designs may require interpretation and adaptation.
• Amazon est un employeur engagé pour l'égalité des chances.
  - Nous sommes convaincus qu'une main d'oeuvre diversifée est essentielle à notre réussite.
  - Nous prenons nos décisions de recrutement en fonction de votre expérience et de vos compétences.
  - Nous apprécions votre envie de découvrir, d'inventer, de simplifier et de construire.
  - La protection de votre vie privée et la sécurité de vos données constituent depuis longtemps une priorité absolue pour Amazon.
  - Veuillez consulter notre Politique de Confidentialité pour en savoir plus sur la façon dont nous collectons, utilisons et traitons les données personnelles de nos candidats.
  - Our inclusive culture empowers Amazonians to deliver the best results for our customers.

If you have a disability and need a workplace accommodation or adjustment during the application and hiring process, including support for the interview or onboarding process, please visit https://amazon. jobs/content/en/how-we-hire/accommodations for more information.

If the country/region you’re applying in isn’t listed, please contact your Recruiting Partner.

Amazon is an equal opportunity employer and does not discriminate on the basis of protected veteran status, disability, or other legally protected status.

Veterans, military spouses, and people with disabilities are encouraged to apply.

#J-18808-Ljbffr