Senior Thermofluids Engineer

Industrial power turbines haven't seen meaningful innovation in over a century. We believe that the modern world should not be limited by energy. Lazarus is a team with over 50 years of turbomachinery analysis, design, and testing experience. We are building the next generation of power conversion technologies that will solve today’s power demands and tomorrow’s renewable energy future. This is a rare chance to help define a new era of hardware energy products by leading core technology development from concept to test and production. Lazarus is post-stealth and pre-series A. We are moving incredibly fast with a talented team in place, hardware in the door, and active testing underway. We are currently building a MW-class system to fire with natural gas and then integrate with nuclear heat before the end of 2027.

Role Overview This role owns the heat exchangers in our sCO₂ power blocks. This includes the recuperator, primary heat exchanger, and air cooler that collectively set the performance and size of our entire system. Working directly with the founding team, you will size and design compact, high performance heat-exchange hardware for our MW-level unit. This role blends thermal and fluidic design of high-pressure / high-temperature cores on aggressive timelines.

Responsibilities

• Lead thermofluid design of the recuperator, primary HX, and air cooler for the MW unit.

• Own effectiveness/NTU, pressure-drop sizing, and channel geometry of the heat exchanger cores.

• Own performance prediction across the steady-state and off-design envelope.

• Drive 1D/network thermal-hydraulic modeling and 3D CFD for sizing, header / manifold design, and flow uniformity

• Coordinate with the cycles, structures, and manufacturing leads on state points, interfaces, and sizing

• Own vendor and fabricator coordination for all heat exchangers from design hand-off through build and acceptance

• Support build, inspection, and test of heat-exchange hardware.

Required Qualifications

• Bachelor’s degree or higher in mechanical or aerospace engineering or similar.

• Strong fundamentals in heat transfer, fluid mechanics, and thermodynamics

• Experience with heat-exchanger thermal-hydraulic design and sizing (effectiveness/NTU, pressure drop, heat transfer prediction)

• Proficiency in 1D/network modeling and 3D CFD (conjugate heat transfer preferred)

• Experience taking heat-exchanger designs into fabricated hardware (either internally or working with vendors)

• Excellent communication and leadership skills and a willingness to learn / teach

Preferred Experiences

• Experience with supercritical CO₂ heat exchangers / hardware

• Compact / high effectiveness heat exchangers (PCHE, microchannel, plate-fin)

• Additively manufactured heat exchangers

• Air-cooled heat exchangers / dry cooling and heat-rejection design.

• Fired heaters, burners, or direct/indirect-fired heat exchangers, including combustion-side design

• Mechanical design of pressure containing HX cores, including thermal stress, creep, pressure-boundary sizing, etc.

• Heat-exchanger test and model-to-test correlation

• ASME BPVC familiarity for heat-exchange hardware.

• Early stage or start-up experience.

Compensation & Benefits

• US salary range: $150,000 - $230,000

• Meaningful equity ownership

• Company wide medical, dental, and vision insurance

• Fully stocked kitchen with snacks, coffee, and lunch

Think this is your kind of work? We move fast and we build real things. If that's the work you're after, send us your application.

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