Thermal Design Engineer

ALTEN is a global engineering and technology consultancy operating across over 35 countries worldwide. We partner with industry leaders across sectors including Aeronautics, Aerospace, Defence, Naval, Automotive, Energy, Rail, IT and many more to deliver innovative engineering solutions that drive technological advancement & support sustainable transformation. Our teams of passionate and agile engineers work on cutting-edge projects that shape the future of technology and sustainability. At ALTEN, we empower talented engineers to innovate, solve complex challenges, and deliver impactful solutions that build tomorrow’s world—today. Join us and start building tomorrow’s world today! As a Senior Thermal Systems Design Engineer , you will join our engineering team to support our activities within the aerospace sector. You will play a key role in the design and development of thermal management systems for advanced electric propulsion products, including electric motors, electronic control units, and complete Electric Propulsion Units (EPUs). Working at the forefront of electrification technology, you will combine expertise in thermodynamics, fluid mechanics, and heat transfer to develop innovative, manufacturable solutions that optimise performance, efficiency, and durability. Location: Bicester On Site: Hybrid Clearance: Clearable Experience Level: Senior (5-15 years of experience) Key Responsibilities: Own the thermal system design for electric propulsion products and associated technologies Develop thermal management solutions for motors, power electronics, and complete Electric Propulsion Units (EPUs) Analyse and optimise sealed liquid cooling systems, including heat exchangers, pumps, coolant circuits, and airflow management Perform thermal and fluid flow simulations to support product development activities Validate analysis results against real-world operating conditions and provide engineering recommendations Specify cooling system components, including pumps, heat exchangers, and airflow requirements Support the development of innovative thermal management concepts to improve product performance and durability Guide and support junior CAE Engineers, Designers, and Systems Engineers during the design process Work closely with suppliers and customers to resolve technical challenges and deliver optimal engineering solutions Ensure designs are suitable for assembly, manufacture, and volume production Produce technical specifications, reports, and engineering documentation throughout the product lifecycle Support testing and validation activities to verify analytical models and design assumptions Required Skills: Strong background in thermal engineering, thermodynamics, fluid mechanics, and heat transfer Experience designing thermal systems for complex engineering products Practical understanding of electric machines, rotating equipment, or electromechanical systems Experience with Computational Fluid Dynamics (CFD) and thermal analysis techniques Proficiency with engineering analysis tools such as ANSYS Fluent or equivalent CFD software Ability to assess complex engineering problems and develop practical, manufacturable solutions Strong communication and stakeholder management skills Experience working effectively within multidisciplinary engineering teams Self-motivated and able to work independently with minimal supervision Required Qualifications: A Bachelor’s or Master’s degree in Engineering , or equivalent military experience . Proven experience delivering thermal design solutions for advanced engineering products Experience supporting products through design, analysis, testing, and validation phases Strong understanding of engineering development processes and product lifecycles Desirable Skills: Experience within electric propulsion, electrification, electric vehicles, aerospace, or advanced mobility sectors Knowledge of electric motor cooling and power electronics thermal management Experience with Python, MATLAB, LabVIEW, or similar engineering software Understanding of Design for Manufacture (DfM) and Design for Assembly (DfA) principles Experience working with external suppliers and customers on technical development projects Familiarity with physical testing and correlation of simulation results Why join us? We bring together entrepreneurial, tech-driven people to deliver innovative solutions for leading companies. At ALTEN, you’ll work on exciting projects, supported by ongoing learning, mentoring, and clear career development tailored to your goals. Join a passionate team and help build tomorrow, today. In short you get: A personalised career path and a rewarding management style A huge diversity of engineering projects and industries Private Medical Insurance Cycle & Tech Scheme Employee assistance programme Life insurance & Pension Scheme Social atmosphere, regular gatherings & team buildings Flexible way of working (role dependent) We are proud to support the Armed Forces Covenant & actively encourage applications from members of the Armed Forces community, including veterans, reservists, service leavers, and military spouses/partners. We recognise the value of military skills and experience and are committed to ensuring that no applicant is unfairly disadvantaged during our recruitment and selection processes. ALTEN is committed to fostering a diverse and inclusive workplace and values the strength that comes from a global mix of backgrounds and perspectives. We welcome applications from all suitably qualified candidates, regardless of background or protected characteristics under the Equality Act 2010. If you require any reasonable adjustments during the recruitment process, please let us know. This role may require you to have or be willing to go through Security Clearance. As part of the onboarding process candidates will be asked to complete a Baseline Personnel Security Standard; details of the evidence required to apply may be found on the government website Gov.UK. If you are unable to meet this and any associated criteria, then your employment may be delayed, or rejected . Details of this will be discussed with you at interview.