Principal Reactor Simulation Engineer

Hadron Energy, Inc.; United States; Remote; USD 180,000 - 260,000; Full time

Job summary

Hadron Energy, Inc. is seeking a Principal Reactor Simulation Engineer, a senior remote role in the United States.

You will lead high-fidelity thermal-hydraulic modeling and integrated plant simulations for Hadron Energy's micro modular reactor program, supporting design, licensing, and operator training. The role requires 15+ years in nuclear engineering with deep expertise in reactor thermohydraulics, transient analysis, and advanced reactor modeling, and will mentor engineers while

Qualifications

• 15+ years of nuclear industry experience with responsibility in reactor thermal-hydraulics, system simulation, or advanced reactor development.
• Expert-level experience developing RELAP5 models for reactor systems and simulations.
• Experience leading multidisciplinary modeling efforts and communicating results to leadership and regulatory stakeholders.

Responsibilities

• Lead development, verification, and maintenance of RELAP5 thermal-hydraulic models for reactor systems and plant behavior.
• Oversee steady-state and transient analyses supporting design, safety, licensing, and operator training.
• Lead development of engineering simulators and digital twins to support design optimization and licensing analyses.
• Translate results into design recommendations to improve performance, safety margins, and controllability.
• Collaborate across I&C, Safety Analysis, Systems Engineering, and Operations teams to support simulator architecture and plant strategies.
• Establish modeling methodologies, configuration controls, and documentation for regulatory use.

Skills

Thermal-hydraulics

Transient analysis

Plant simulation

Reactor modeling

Technical leadership

Mentorship

Regulatory communication

Education

Bachelor's/Master's/PhD in Nuclear/Mechanical Engineering

Tools

RELAP5

Job description

Hadron Energy specializes in Micro Modular Reactor (MMR) development, design, and research based in the San Francisco Bay Area. As a leading MMR developer, Hadron Energy is designing factory-produced, transportable microreactors that provide 24/7 carbon-free power for data centers, government facilities, industrial sites, and remote communities. Our mission is to create a brighter, healthier, and more equitable energy future.

Role Description

This is a full-time remote role for a Principal Reactor Simulation Engineer, based in the United States. The position is ideal for a highly experienced nuclear engineer with deep expertise in reactor thermal-hydraulics, transient analysis, plant simulation, and advanced reactor modeling who can provide technical leadership across reactor design, licensing, and operational readiness.

The Principal Engineer will lead the development of high-fidelity thermal-hydraulic models and integrated plant simulation capabilities for Hadron Energy's micro modular reactor. This individual will be responsible for developing and maintaining RELAP5-based reactor models, performing steady-state and transient analyses, and translating simulation results into actionable design insights across the engineering organization.

As the reactor design matures, this role will also lead development of Hadron's integrated engineering simulator and digital twin, establishing the analytical foundation for design optimization, control-system development, licensing analysis, operator training, and future reactor operations.

Responsibilities

• Lead development, verification, and maintenance of RELAP5 thermal-hydraulic models representing reactor systems and integrated plant behavior
• Perform and oversee steady-state, transient, and system-response analyses supporting reactor design, safety evaluation, and licensing activities
• Lead development of Hadron's engineering simulator and reactor digital twin, integrating thermal-hydraulics, reactor physics, controls, and plant system models
• Translate simulation results into design recommendations, identifying opportunities to improve reactor performance, safety margins, controllability, and operational efficiency
• Collaborate with I&C, Safety Analysis, Systems Engineering, Reactor Design, and Operations teams to support control-system development, simulator architecture, and plant operating strategies
• Establish simulation methodologies, model configuration controls, verification and validation practices, and technical documentation supporting engineering and regulatory use
• Provide technical leadership and mentorship across thermal-hydraulics, modeling, and simulation activities while supporting NRC licensing and future operator training programs

Qualifications & Skillsets

• Bachelor's, Master's, or PhD in Nuclear Engineering, Mechanical Engineering, or a closely related technical discipline
• 15+ years of nuclear industry experience with significant technical responsibility in reactor thermal-hydraulics, system simulation, or advanced reactor development
• Expert-level experience developing and applying RELAP5 models for reactor systems, transient analysis, and integrated plant simulations
• Deep understanding of reactor thermal-hydraulics, heat transfer, fluid mechanics, plant systems, and transient behavior
• Demonstrated experience developing engineering simulators, plant simulators, digital twins, or integrated dynamic reactor models
• Experience supporting reactor design, safety analysis, licensing, I&C/control-system development, or operator training through simulation and analytical modeling
• Proven technical leadership with the ability to lead complex multidisciplinary modeling efforts, mentor engineers, and communicate simulation results to engineering leadership and regulatory stakeholders