Senior Nuclear Reactor Simulation & Validation Engineer

Radiant; El Segundo (CA); On-site; USD 120,000 - 190,000; Full time

Benefits offered by this job

Stock option package

Medical and family benefits

Daily catered lunch

Onsite headquarters near Pacific Ocean

Job summary

Radiant, based in El Segundo, CA, seeks a Simulation Engineer to design tests, collect data, and validate in-house reactor simulations. You will anchor models to real data, run experiments with the materials team, and provide rigorous V&V to support regulatory processes.

You will collaborate across the simulation software team, working hands-on in a fast-paced, early-stage environment. Strong communication and decisive technical judgment are essential.

Qualifications

• Bachelor’s degree required; advanced degree preferred.
• Hands-on V&V experience with manufactured solutions, code-to-code comparison, convergence analysis, and validation against data.
• Ability to design meaningful experiments with a materials team and interpret results.
• Strong data science and uncertainty quantification skills.
• Experience with simulations and scripting in Python/MATLAB; familiarity with CI workflows.

Responsibilities

• Build and maintain a verification program for simulation tools, including manufactured solutions and automated regression testing.
• Compare simulation results against software and investigate root causes of differences.
• Validate models against reactor data and experiments you design.
• Collaborate with materials lab to design experiments covering required scenarios.
• Create digital representations of experiments in the simulation environment.
• Run convergence studies to assess correctness and validity of results.
• Quantify uncertainty and report with defensible confidence bounds.
• Identify missing physics and guide model enhancements.
• Produce V&V documentation meeting QA and regulatory standards.

Skills

V&V experience

Data science & uncertainty quantif.

Design of experiments

Python

MATLAB

Stakeholder communication

Scripting analyses

Version control & CI

Education

Bachelor’s degree in mechanical, nuclear, aerospace, or materials engineering; applied mathematics or related field

Advanced degree preferred

Tools

STAR-CCM+

Abaqus

NX CAD

Python

Git/CI tooling

Job description

Radiant, based in El Segundo, CA, seeks a Simulation Engineer to design tests, collect data, and validate in-house reactor simulations. You will anchor models to real data, run experiments with the materials team, and provide rigorous V&V to support regulatory processes.

You will collaborate across the simulation software team, working hands-on in a fast-paced, early-stage environment. Strong communication and decisive technical judgment are essential.