Finite Element Analysis (FEA) Mechanical Engineer

Deep Fission is a nuclear technology company pioneering the development of a revolutionary deep borehole pressurized water reactor. We recently completed a private placement financing and Alternative Public Offering and are now operating as a public company while maintaining our startup agility and innovation focus. With strategic partnerships in place, strong private and public investment, and active engagement with the U.S. Nuclear Regulatory Commission (NRC), we are executing our next phase of growth as we advance our groundbreaking nuclear technology toward commercial deployment. 

Job Summary

Deep Fission is seeking a highly skilled FEA (Finite Element Analysis) Mechanical Engineer to join our engineering team. This role is central to ensuring the structural integrity, thermal performance, and safety of nuclear reactor components and systems through advanced computational modeling and simulation. The FEA Mechanical Engineer will perform complex analyses on pressure vessels, piping systems, reactor internals, and supporting structures, directly contributing to reactor design validation, licensing submittals, and regulatory compliance. This is an outstanding opportunity for an engineer passionate about applying advanced simulation techniques to solve critical challenges in next-generation nuclear energy. 

Key Responsibilities: 

• Perform finite element analyses (linear, nonlinear, static, dynamic, and thermal) on nuclear reactor components including pressure vessels, heat exchangers, piping systems, reactor internals, and structural supports. 
• Develop, validate, and maintain high-fidelity FEA models using industry-standard software such as ANSYS, Abaqus, NASTRAN, or equivalent tools. 
• Conduct stress, fatigue, fracture mechanics, creep, and buckling analyses in accordance with ASME Boiler and Pressure Vessel Code (BPVC) Section VIII or III and other applicable codes and standards. 
• Perform thermal-hydraulic and coupled multiphysics simulations to evaluate component behavior under normal operating, transient, and accident conditions. 
• Support reactor design efforts by providing analytical justification for material selection, geometry optimization, and design modifications. 
• Prepare detailed analysis reports, calculation packages, and technical documentation suitable for internal design reviews and regulatory submittals. 
• Collaborate with multidisciplinary teams including nuclear engineers, structural engineers, CAD designers, and licensing specialists to integrate FEA results into overall design packages. 
• Develop and maintain analysis procedures, quality assurance documentation, and verification/validation (V&V) protocols for FEA software tools and methodologies. 
• Perform mesh sensitivity studies, convergence analyses, and benchmark validations to ensure the accuracy and reliability of simulation results. 
• Evaluate and disposition weld residual stresses, thermal gradients, and seismic loading effects on critical components. 
• Mentor junior engineers and contribute to the development of the team’s FEA capabilities and best practices. 

Required Skills & Experience: 

• Bachelor’s or Master’s degree in Mechanical Engineering, Structural Engineering, or a closely related engineering discipline. 
• Minimum of 5–8 years of professional experience performing FEA in an engineering environment, with at least 2 years in the nuclear, power generation, aerospace, or similarly regulated industry. 
• Advanced proficiency in one or more FEA software platforms: ANSYS Mechanical, Abaqus, NASTRAN, or equivalent. 
• Strong working knowledge of ASME BPVC Section III or Section VIII for nuclear component design and analysis. 
• Experience with stress classification, fatigue evaluation (including environmental fatigue), and fracture mechanics methodologies per ASME code requirements. 
• Demonstrated expertise in thermal analysis, contact mechanics, and nonlinear material modeling. 
• Proficiency in pre-/post-processing tools and CAD software (e.g., SolidWorks, NX, CREO, SpaceClaim) for model preparation. 
• Strong understanding of material properties and behavior under high-temperature, irradiation, and corrosive environments relevant to nuclear applications. 
• Excellent technical writing skills with the ability to produce clear, well-organized analysis reports and calculation packages. 
• Effective communication and collaboration skills for working across multidisciplinary engineering teams. 
• Must be a U.S. citizen or authorized to work in the United States. 

Desired Skills & Experience: 

• Direct experience with nuclear reactor component analysis, including pressure vessels, heat exchangers, core support structures, or primary system components. 
• Experience with seismic analysis (response spectrum, time-history) for nuclear safety-related structures, systems, and components (SSCs). 
• Experience with computational fluid dynamics (CFD) tools for coupled thermal-hydraulic/structural analyses. 
• Knowledge of probabilistic fracture mechanics and risk-informed analysis methods. 
• Experience developing automated analysis workflows using Python, APDL, or equivalent scripting languages. 
• Familiarity with nuclear quality assurance programs (NQA-1) and configuration management practices. 

Our Commitment: 

Deep Fission is an equal opportunity employer committed to building a diverse and inclusive workplace. We welcome applicants from all backgrounds who share our passion for advancing clean nuclear energy and creating a sustainable future. We do not discriminate on the basis of race, color, creed, religion, ancestry, age, sex, marital status, national origin, disability, veteran status, or any other characteristic protected by applicable law.