Senior Thermal-Hydraulics Analysis Engineer

About the role

This role leads system-level thermal-hydraulics modelling for advanced nuclear energy systems. The position operates within the Engineering organization's Models & Simulations team, focusing on computational analysis and performance prediction.

Software engineers turn product ideas into working code. Engineers work in small teams, review each other's work, and ship in small batches. Most teams follow agile practices such as sprints and daily standups. Engineers also write tests, fix bugs, and improve performance. The field values clear communication as much as technical skill. Engineers spend part of every week on planning, code review, and debugging, not just writing new code. The ability to explain a technical decision in plain words separates strong engineers from the rest.

Key facts

What you'll do

Verification and validation of system models is led, systems-modelling standards are defined, regulator and customer reviews are supported, and junior systems analysts are mentored within the team.

Requirements

A Bachelor's degree or higher in Mechanical, Nuclear, Chemical or Aerospace Engineering with emphasis on thermodynamics, heat transfer, or thermal-hydraulics systems is required.

5+ years of professional thermal-hydraulics or plant-systems analysis experience, including lead responsibility on integrated system or cycle models, is required.

Preferred Skills and Experience

A Master's degree (MSc/MEng) or higher in Mechanical, Nuclear, Chemical or Aerospace Engineering with emphasis on thermodynamics, heat transfer, or thermal-hydraulics systems is preferred.

Demonstrated expertise in Flownex SE or an equivalent systems/transient code such as RELAP5, TRACE, GOTHIC, MELCOR, Modelica/Dymola, Aspen HYSYS Dynamics, Thermoflow, or GateCycle is strongly preferred.

Applied thermodynamics, heat transfer, and fluid mechanics fundamentals are applied, with specific experience in closed-loop power-cycle design for Brayton and supercritical-CO₂.

Heat-exchanger thermal and hydraulic design and rating, turbomachinery and pump performance characterization, and control-system representation in system models are performed.

Transient and dynamic simulation, including reactor thermal-hydraulics and decay-heat / natural-circulation scenarios, is executed.

Property libraries and equations of state, such as CoolProp or REFPROP, are used, and working experience with helium, molten-salt, sodium, or CO₂ as working fluids is a strong plus.

Experience under a nuclear or regulated quality programme, including NQA-1, ISO 9001, and 10 CFR 50 Appendix B, with exposure to NRC and ASME environments, is required.

Scripting and automation within defined workflows and quality assurance frameworks are implemented.

Technical systems analysis leadership and mentoring within the team are provided.

Practical notes

U.S. citizenship or lawful permanent residency is required.

Typical interview steps

Hiring for engineering roles usually starts with a recruiter screen, followed by one or two technical rounds. Candidates often solve a coding problem, discuss past projects, and answer system design questions. Some loops include a take-home task. Final rounds typically cover team fit and give candidates a chance to ask questions. Interviewers look for how you break down an unfamiliar problem, not just whether you reach the answer. Practicing a few problems aloud and reviewing your own past projects are the best preparation.

Good to know

Thermal-hydraulics analysis supports energy, hydrogen, and next-generation manufacturing applications.

Advanced nuclear systems and fuel fabrication aim to enable fast deployment and factory-made solutions.

The role uses Flownex SE alongside CFD and FEA tools for system-level design and safety analysis.

Career growth

Engineering careers usually progress from individual contributor to senior, staff, and principal levels. Some engineers move into management and lead teams of five to twenty people. Others stay on the technical track. Growth follows demonstrated impact, not tenure alone. A typical engineering ladder has clear levels with defined expectations for scope, quality, and mentorship. Moving up usually requires owning outcomes end to end rather than completing assigned tickets.