Nuclear Engineer III/IV(Thermal Hydraulics)

Position title : Nuclear Engineer III/IV (Thermal Hydraulics)

Location :

Madison, WI About Us :

As an emerging leader in nuclear engineering, our startup is developing revolutionary reactor technology to secure safe and abundant energy for future generations. We are seeking a highly skilled Nuclear Engineer III (Thermal Hydraulics) to join our dynamic team and contribute to the design and development of next-generation nuclear reactors.

Job Summary :

The Nuclear Engineer III (Thermal Hydraulics) will contribute to the design, analysis, and optimization of molten salt nuclear reactor systems. The ideal candidate will have a strong background in molten salt systems, proficiency with industry-standard design software, and a proactive, self-starting attitude. This role requires innovative thinking, technical expertise, and a commitment to advancing safe and sustainable nuclear energy solutions.

Key Responsibilities :

Conduct thermal-hydraulic design and analysis of the salt loops, storage tanks, heat exchangers and power conversion, including start-up, steady-state, and transient conditions. Develop specifications and support design of critical components heat exchangers, pumps, valves, measurement systems and fluid transfer systems Help design and run the integration of the reactor loops with heat rejection and power conversion systems as required. Develop and maintain thermal-hydraulic models using appropriate tools Support safety analyses for licensing-basis events and beyond-design-basis events including loss-of-flow, loss-of-heat-sink, reactivity transients, and freeze/thaw scenarios. Specify and support selection of instrumentation relevant to thermal-hydraulic performance monitoring Oversee and conduct thermal-hydraulic testing, including separate-effects tests, integral tests, and validation experiments for model benchmarking. Contribute to design requirements, safety classification, and functional specifications in compliance with nuclear standards Perform uncertainty quantification, sensitivity studies, and validation & verification (V&V) of thermal-hydraulic models. Support licensing efforts by preparing technical reports, responding to regulatory questions, and providing thermal-hydraulic justification for design decisions. Help to develop strategy for team growth: define roles, recruit, mentor, and build a high-performing thermal hydraulics group as the project matures. Maintain comprehensive documentation, including design basis reports, calculation packages, and configuration management, including QA documentation of testing.

Required Qualifications:

Bachelor's degree in Nuclear Engineering, Mechanical Engineering, Chemical Engineering, or a closely related field. Master's degree or PhD strongly preferred. Minimum 10 years of direct experience in thermal-hydraulic analysis and design, with at least 5 years in safety-critical or highly regulated industries.

Deep expertise in:

Thermal-hydraulic phenomena in liquid-cooled systems (single- and multi-phase flow, heat transfer, natural circulation, transient analysis). System-level and CFD modeling tools relevant to nuclear or high-temperature applications. Nuclear safety analysis methods and regulatory requirements for thermal-hydraulic performance. Experimental design and interpretation of thermal-hydraulic test data. Instrumentation challenges in extreme environments. Proven ability to lead technical efforts, develop and execute test programs and build teams Strong understanding of nuclear quality assurance Excellent analytical, problem-solving, and communication skills. U.S. citizenship or permanent residency required.

Preferred Qualifications:

Direct experience with molten salt reactors (MSRs), fluoride salts, or other Gen IV advanced reactor concepts. Hands-on experience with molten salt properties Understanding of molten salt thermal and flow impacts on erosion, corrosion and plate-out. Proficiency in multi-physics simulation platforms Experience supporting NRC or international regulatory interactions for thermal-hydraulic topical reports. Knowledge of risk-informed performance-based approaches Professional Engineer (PE) license or equivalent certification.

What We Offer:

Competitive salary Comprehensive benefits including medical, dental and vision Paid time off, sick leave and holidays Bereavement leave If you are passionate about the energy that impacts our day-to-day lives and want to work with talented and dedicated people across the globe, apply today! www.fissionaire.com Fissionaire is an Equal Opportunity Employer that does not discriminate on the basis of actual or perceived race, colour, creed, religion, national origin, ancestry, citizenship status, age, sex or gender (including pregnancy, childbirth, pregnancy-related conditions, and lactation), gender identity or expression (including transgender status), sexual orientation, marital status, family or relationship structure, military service and veteran status, physical or mental disability, genetic information, gender identity, or any other characteristic protected by applicable federal, state, or local laws and ordinances. Fissionaire's management team is dedicated to this policy with respect to recruitment, hiring, placement, promotion, transfer, training, compensation, benefits, employee activities, access to facilities and programs, and general treatment during employment.

Pay:

$125,000.00 - $189,000.00 per year

Benefits:

Dental insurance Health insurance Life insurance Paid time off Relocation assistance Vision insurance

Experience:

Thermal hydraulic analysis and design: 10 years (Preferred)

Work Location:

In person