Senior Thermal-Hydraulics Engineer – Equity & Growth

Valar Atomics Inc.; Torrance (CA); On-site; USD 151,000 - 185,000; Full time

Benefits offered by this job

Equity ownership in a rapidly growing,

Unlimited PTO

Free daily lunch and dinner onsite

Generous PPE stipend

High-impact startup environment

Internal career growth

Direct collaboration with experienced,

op leaders

Job summary

Valar Atomics seeks a Senior Thermal-Hydraulics Systems Engineer to lead 1-D network modelling of the reactor's primary/secondary loops, balance of plant, and power-conversion cycles using Flownex SE for steady-state and transient analyses.

The role involves defining modelling approaches, reconciling results with CFD-derived data, and feeding inputs to safety analyses. You will mentor junior analysts within the ModSim Engineering Group and contribute to design decisions.

Qualifications

• Bachelor's degree or higher in Mechanical, Nuclear, Chemical or Aerospace Engineering with emphasis on thermodynamics, heat transfer or thermal-hydraulics systems.
• 5+ years of professional thermal-hydraulics / plant-systems analysis experience, including lead responsibility on integrated system or cycle models.

Responsibilities

• Build, run and maintain integrated Flownex SE network models of primary/secondary loops, balance of plant and power-conversion cycles for steady-state and transient analysis.
• Characterize and size components (pumps, compressors, heat exchangers, valves, turbomachinery) and evaluate cycle performance and optimization across Brayton and sCO₂ architectures as required.
• Analyze plant transients and control response (start-up/shutdown, load-follow, loss-of-flow, trips) and provide system boundary conditions to the CFD and FEA streams while consuming their loss/heat-transfer coefficients.
• Produce calculation packages and system design-basis documentation under NQA-1; provide inputs to safety analysis and interface with detailed CFD models and neutronics power distributions.
• Lead verification and validation of system models, set systems-modelling standards, support regulator/customer reviews, and mentor junior systems analysts.
• Mentor engineers and train junior team members
• Standardize Flownex modelling methods, component libraries and templates, and support the Stream Lead in scoping, estimating and scheduling systems work.

Skills

Thermal-hydraulics

System analysis

CFD/FEA

Mentoring

Scripting/automation

Leadership

Education

Bachelor's degree in Mechanical/Nuclear/Chemical/Aerospace Engineering

Master’s degree preferred

Tools

Flownex SE

RELAP5/TRACE/GOTHIC/MELCOR

CoolProp/REFPROP

Modelica/Dymola

Python/Scripting

Job description

Valar Atomics seeks a Senior Thermal-Hydraulics Systems Engineer to lead 1-D network modelling of the reactor's primary/secondary loops, balance of plant, and power-conversion cycles using Flownex SE for steady-state and transient analyses.

The role involves defining modelling approaches, reconciling results with CFD-derived data, and feeding inputs to safety analyses. You will mentor junior analysts within the ModSim Engineering Group and contribute to design decisions.