Senior Engineer, Plant Thermal Hydraulic Methods

Senior Engineer, Plant Thermal Hydraulic MethodsSystem One is seeking a Senior Engineer, Plant Thermal Hydraulic Methods to support our client on a contract basis.ResponsibilitiesDevelop system-level thermal hydraulic analysis methods, including modeling strategies, numerical approaches, and closure models.Perform steady-state and transient system-level analyses to characterize model behavior, assess method performance, and define method fidelity requirements.Support method qualification, including numerical verification, applicability envelopes, and performance characterization.Formulate and integrate closure models and empirical correlations (e.g., heat transfer, pressure drop, mixing, component-level physics) into existing analysis frameworks.Identify modeling gaps and support method enhancement using sensitivity studies.Develop automated workflows and tools for model setup, execution, post-processing, and repeatable method application.Document modeling methodologies, assumptions, method applicability, and numerical performance for design processes and licensing support activities.Work across disciplines to ensure thermal hydraulic methods integrate effectively with plant design, safety analysis, and coupled simulation workflows.Apply and improve SQA and NQA 1 modeling practices, ensuring traceability, configuration control, and reproducibility of methods.RequirementsDegree in Mechanical, Nuclear, Chemical Engineering, or similar fields.6+ years of experience in system-level thermal hydraulic modeling and method development for nuclear or complex energy systems.Demonstrated experience in developing or improving analysis methods, including numerical scheme development, closure model formulation, and stability/accuracy optimization strategies.Experience performing system-level thermal hydraulic analyses using tools such as RELAP5 3D, GOTHIC, SAS, or equivalent.Strong foundation in thermal fluids and reactor system behavior, including complex thermal hydraulic phenomena relevant to advanced reactor designs.Experience in sensitivity analyses and model gap identification that support method development priorities.Familiarity with scientific programming and workflow automation (e.g., Python, MATLAB).Familiarity with NQA 1 quality assurance for modeling workflows, including documented methodologies, configuration control, and model traceability.Strong analytical thinking, clear technical communication, and the ability to support multiple method development efforts in parallel.Strong communication skills; high degree of trust and integrity, open communication, respect, and teamwork orientation.