Senior Engineer, Core Thermal Hydraulics Methods and Analysis

TerraPower · Bellevue, WA

Posted 8/18/2026 · last confirmed live 8/26/2026

  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. 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.  Senior Engineer, Core Thermal Hydraulics Methods and Analysis The Senior Engineer reporting to the Manager of Core Thermal Hydraulics Methods and Analysis develops and applies thermal‑hydraulic analysis methods, performs code validation, applies first‑principles calculations, and integrates with multidisciplinary teams to solve reactor‑core design challenges and support testing programs. The role provides technical recommendations through formal documentation and presentations, requiring strong analytical skills, expertise with nuclear systems codes, and the ability to work concurrently across multiple complex tasks. Responsibilities Develop and apply thermal-hydraulic analysis methods, including steady state and transient one-dimensional network hydraulic analyses Computational analysis of in-core steady-state thermal hydraulic phenomena Perform code benchmarking and validation analyses to support code qualification and methodology development Perform calculations using first principles of heat transfer, fluid dynamics, and thermodynamics to support and validate analysis results Integrate with other engineering groups performing aspects of component, system, fuel, and control system analysis and related thermal-hydraulic testing Support development of testing programs needed for reactor core & components Support the technical decision to address the critical challenges in reactor core design Support the project planning and define the work scopes for the critical path of the project Work with cross-disciplinary teams to analyze the thermal and mechanical design considerations for the safety of the reactor and its components Provide technical presentations on analyses performed to the broader team. Prepare informal and formal reports to document findings and make reasoned recommendations, and report to core thermal hydraulic team manager/lead Key Qualifications and Skills Minimum of 6 years of related experience with Bachelor’s degree; or 3 years and a Master’s degree. PhD without commercial experience may be acceptable with relevant research or expertise. Programming language proficiency in either python or C++ a plus Experience with a nuclear systems code, or subchannel analysis code (e.g. RELAP, SASSYS, GOTHIC, VIPRE-01) a plus Demonstrated ability to participate on a multi-disciplinary team of engineers Experience with analysis of nuclear reactor core subchannel analysis a plus Experience with low Prandtl number heat transfer analysis a strong plus Experience with high temperature thermal-fluid systems (e.g. sodium) a plus Creative thinker with demonstrated strong analytical/problem solving skills Ability to work on multiple tasks concurrently during a given work week Excellent writing and communication skills The successful candidate will possess a high degree of trustworthiness and integrity, communicate openly and display respect and a desire to foster teamwork This position is subject to qualification requirements in accordance with ANSI/ANS 3.1. Candidates must meet the minimum education and experience criteria applicable to the role, including relevant nuclear industry experience where required. Verification of data will be part of the hiring process. Job Functions: Job Functions are physical actions and/or working conditions associated with the position. These functions may also constitute essential functions for the job which the employee must be able to fulfill, with or without accommodation.  Information provided below is to help describe the job so that the applicant has a reasonable understanding of the job duties/expectations.  An applicant's ability to perform and/or tolerate these actions and conditions will be discussed and workplace accommodations may be made on a case-by-case basis following an individualized assessment of the applicant and other considerations, including but not limited to any governing safety standards. Motor Abilities: Sitting for extended periods, bending/stooping, grasping/gripping, fine motor control (hands) Physical exertion and/or requirements: Minimal, with ability to safely lift up to 25 pounds. Repetitive work: Prolonged Special Senses: Visual and audio focused work Work Conditions: Stairs, typing/keyboard, standard and/or sitting working environment of >8 hours/day Travel required 0-10% TerraPower’s technology is controlled for export by various agencies of the U.S. Government.  TerraPower must evaluate applicants who are foreign nationals (other than asylees, refugees, or lawful permanent residents) in accordance with U.S. Government export control requirements.  To facilitate TerraPower’s export control reviews, you will be asked as part of the application process to identify whether you are a U.S. Citizen or national, asylee, refugee, or lawful permanent resident of the United States.  Government export authorization approval times vary.  Based on the business needs for a particular position, TerraPower may not consider a foreign national from a country if it is impracticable to obtain timely Government export approval. Job details Salary Range: $131,828 - $171,206 Any salary offered within the posted salary band is based on market data and commensurate with the selected candidate’s qualifications and experience. This range is specific to Washington State. Job Type: Full-time Benefits: Competitive Compensation Salary, eligible to participate in discretionary short-term incentive payments Comprehensive Medical and Wellness Benefits Medical Vision Dental Life and Disability Gender Affirmation Benefits Parental Leave 401k Plan Generous Paid Time Off (PTO) 21 days of annually accrued PTO Generous Holiday Schedule 10 paid holidays Relocation Assistance Professional and Educational Support Opportunities TerraPower Career and Benefits information:  https://www.terrapower.com/contact-us/careers/    

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