Thermal-Hydraulics and Safety Analysis Engineer - Isotopes

Role overview Develop systems-level thermal-hydraulic analyses that support reactor safety evaluations, design decisions, and licensing. The role combines transient modeling with safety-method development, including justification of assumptions, assessment of model applicability, uncertainty evaluation, and preparation of reviewable technical evidence. Its scope centers on thermal-hydraulic response rather than source-term, radiological-consequence, or severe-accident progression analysis.

Responsibilities - Build, maintain, and run reactor and plant transient models using RELAP5 or comparable systems-analysis tools. - Evaluate normal operation, anticipated operational occurrences, design-basis events, and selected beyond-design-basis conditions. - Define event-specific assumptions, initial and boundary conditions, acceptance criteria, figures of merit, and uncertainty treatment. - Assess code and model applicability; conduct verification, validation, sensitivity, uncertainty, scaling, and benchmark comparisons. - Translate regulatory requirements into analysis methods and defensible evaluation strategies, identifying evidence gaps and ways to address them. - Prepare calculation packages, methods documents, safety reports, licensing material, and responses to regulator questions; review analyses from colleagues and suppliers.

Requirements - Degree in nuclear, mechanical, chemical, aerospace, or a closely related engineering field. - At least five years in reactor thermal-hydraulics, nuclear safety, transient analysis, or a related area; relevant graduate education may replace some experience. - Demonstrated experience developing and running systems-level transient models with RELAP5. - Strong grounding in heat transfer, fluid mechanics, thermodynamics, and reactor thermal-hydraulics. - Experience analyzing reactor transients or accident scenarios and judging the validity of models, correlations, assumptions, and results. - Ability to produce clear, reviewable engineering documentation and work independently across engineering and licensing disciplines.

Nice to have Experience with verification and validation, uncertainty quantification, sensitivity analysis, scaling, bias evaluation, or code-applicability assessments.