Principal Engineer, Plant Thermal Hydraulics Validation

&nbsp; TerraPower is a nuclear technology company based in Bellevue, Washington. At its core, the company is working to raise living standards globally through a more affordable, secure, and environmentally friendly form of nuclear energy along with innovations in medical isotopes to improve human health. In 2006, TerraPower originated with Bill Gates and a group of like-minded visionaries who evaluated the fundamental challenges to raising living standards around the world. They recognized energy access was crucial to the health and economic well-being of communities and decided that the private sector needed to take action and create energy sources that would advance global energy deployment. TerraPower’s mission is to be a world leader in new nuclear technologies, while developing innovators and future leaders in the nuclear field. As a result, the company’s activities in the fields of nuclear energy and related sciences are yielding significant innovations in the safety and economics of nuclear power, hybrid energy and medical applications – all for significant human health benefits.” TerraPower is seeking to hire highly motivated and forward-thinking professionals who are interested in focusing on advanced nuclear reactor research and development and influencing change within the nuclear power landscape and bringing forward the critical production of medical isotopes.&nbsp; TerraPower is an Equal Opportunity Employer. We do not discriminate in hiring on the basis of sex, gender identity, sexual orientation, race, color, religious creed, national origin, physical or mental disability, protected Veteran status, or any other characteristic protected by federal, state, or local law.&nbsp; Principal Engineer, Plant Thermal Hydraulics Validation This role supports validation activities for the Natrium Reactor’s plant‑scale thermal‑hydraulic analysis tools. Reporting to the Manager, Plant Thermal Hydraulics Validation, the engineer supports verification, validation, uncertainty quantification, and comprehensive code assessment. The position requires expertise in system‑level thermal‑hydraulics, thermal‑fluids behavior, fluid‑structure interaction, and benchmarking computational models against high‑quality experimental data. Responsibilities Support verification, validation, and uncertainty quantification activities for plant scale thermal-hydraulic analysis tools. Perform system-level steady-state and transient thermal-hydraulic simulations to evaluate model behavior, accuracy, and limitations. Develop and execute code assessment plans, including validation matrices, test selection, and quantitative comparison methodologies. Interpret and apply experimental data from separate effects and integral test facilities to support model validation and closure of technical gaps. Define validation needs, develop test requirements, and collaborate closely with test engineering teams to ensure alignment between model gaps and experimental programs. Document V&amp;V methodologies, model assumptions, validation results, and uncertainty analyses for internal design processes and regulatory submittals. Collaborate with multidisciplinary teams to support plant design, safety analysis, and licensing workflows. Apply and improve TerraPower’s SQA and NQA1 modeling quality practices and ensure traceability and configuration control of analysis inputs, models, and results. Mentor junior engineers in system modeling, validation methodologies, and best practices in code assessment. Key Qualifications and Skills</str