Sr. Thermodynamics Performance Engineer

Sr. Thermodynamics Performance Engineer

El Segundo, CA

About Us

At Arbor Energy & Resources Corporation ("Arbor Energy"), we're creating technology to power our lives while protecting the planet that sustains them. Our advanced power systems deliver clean, reliable baseload electricity with zero operating emissions—modular, fuel-flexible, and engineered for the realities of today's energy demand. At the core is a supercritical CO₂ turbine with integrated carbon capture, designed to bring carbon-neutral power online quickly at meaningful scale.

Our team includes aerospace engineers, combustion experts, and systems thinkers with a shared goal: to build technology worthy of the world we want to live in. While many of us began our journeys looking to the stars, we're applying that expertise here at home to deliver dependable, emission-free baseload power and a future of lasting abundance.

If you share our values and are drawn to rigorous work with lasting impact, we'd love to learn more about you. Come build what the future will run on.

Steward our planet: We build for tomorrow, ensuring every bolt we tighten and every hand we lend leaves our environment stronger than we found it.

Lead with Love: We champion the success of our people, partners, and planet, nurturing excellence through camaraderie and rigor.

Explore the Uncharted: We embrace the unknown with curiosity, using courage and discipline to transform uncertainty into opportunity.

Role Overview

We're looking for a Sr. Thermodynamics Performance Engineer to own the dynamic and steady-state thermodynamic models of our direct-fired supercritical CO₂ Brayton cycle. You'll be the person who turns integrated system behavior into clear, actionable insight — running performance studies ahead of test campaigns, reconciling predictions against test data, and growing our modeling capability into a digital-twin-quality simulation platform that supports controls development, trip response, and eventual hardware-in-the-loop testing. You'll work closely with our test, combustion, turbomachinery, recuperator, fluid systems, and controls engineers. This is the simulation backbone for a first-of-a-kind power system, and the work is foundational to how we operate, validate, and scale the technology.

This is an onsite opportunity in our El Segundo, CA office.

Responsibilities

• Own the integrated cycle performance model — steady-state and dynamic — for our direct-fired sCO₂ Brayton power loop, maintaining and advancing it through the hardware lifecycle
• Run performance prediction and sensitivity studies ahead of test campaigns; reconcile model output against test data to drive model refinement and surface component-level insights
• Own the architecture call on how our dynamic modeling stack should evolve over time — what platform, what fidelity, on what evidence
• Build property tables, turbomachinery map handling, heat exchanger transient models, and combustor representations appropriate to the cycle and fidelity required
• Collaborate with combustion, turbomachinery, and heat exchanger engineers to integrate component data into system-level models; collaborate with controls and software teams on closed-loop simulation and HIL planning
• Develop simulation infrastructure — scripted scenario runs, parameter sweeps, validation cases — that makes the model usable by engineers beyond yourself

Requirements

• Bachelor's degree in Chemical, Mechanical, Aerospace, Nuclear, or related Engineering field
• 6+ years of experience in cycle performance analysis, thermodynamic systems modeling, or dynamic process simulation
• Strong fundamentals in thermodynamics, fluid mechanics, and heat transfer, applied to integrated multi-component systems
• Demonstrated experience building dynamic simulation models of fluid/thermal systems in an industry-grade 1D system simulation platform — and a clear point of view on tool tradeoffs for closed-loop power cycle applications
• Working knowledge of integrated power loop equipment — heat exchanger sizing, compressor/pump curves, valve Cv, piping hydraulics — and how each shows up in dynamic response
• Programming proficiency: Python for data reduction and automation; one of MATLAB/Simulink, Modelica, or equivalent for modeling
• Strong ownership mentality and comfort driving rigorous analysis in a fast-paced startup environment

Preferred Qualifications

• Deep experience with industry dynamic simulation platforms (such as GT-SUITE, Modelica/Dymola, NPSS, Flownex, Simcenter Amesim, or equivalent) applied to turbomachinery, power cycles, or closed-loop thermal-fluid systems
• Background in nuclear thermal-hydraulics with fast-dynamic single-phase modeling experience (RELAP, TRACE, MARS, ATHLET, GAMMA, or equivalent), particularly applied to gas-cooled or sCO₂ reactor concepts
• Working knowledge of real-fluid EOS handling (REFPROP, CoolProp, Span-Wagner) and turbomachinery map interpolation near critical conditions
• History of making and defending tool/methodology decisions in a constrained engineering environment
• Experience with supercritical CO₂, closed Brayton cycles, high-pressure systems (100+ bar), or other high-density working fluids
• Experience coupling plant models to control systems for HIL testing, controller validation, FMU export, or operator training simulators
• Hands-on plant startup, commissioning, or field troubleshooting on first-of-a-kind or developmental systems
• Background in rocketry, gas turbine, advanced reactors, or high-performance turbomachinery environments

Compensation & Benefits

• Pre-IPO stock options
• Medical, dental, and vision insurance (Arbor covers 90% for employees)
• Basic life insurance fully covered
• Health savings account (HSA) with matching
• Flexible savings account (FSA)
• Unlimited PTO
• 12+ company holidays, including Earth Day!
• 401(k)
• Commuter benefits
• Annual learning and development stipend
• And more!

Base Pay: $165,000 - $180,000 USD/year. The salary is subject to the applicant's skills, qualifications, experience, and geographic location.

Our Commitment

Arbor Energy is proud to be an equal opportunity employer. We evaluate qualified applicants without regard to race, religion, national origin, gender identity or expression, sexual orientation, age, marital or veteran status, disability, or any other protected characteristic under applicable law. Solving global energy challenges requires a wide range of perspectives and experiences, and we are committed to building a team that reflects the world we serve.

Our hiring process is designed to be accessible, fair, and focused on the work that matters most for this role. Reasonable accommodations are available throughout the hiring process and employment—please let us know if you need one.