Thermal Design Engineer II / Senior Thermal Design Engineer

• Build, run, and validate CFD models of high-temperature air flows (up to several thousand K) exiting Nitricity’s plasma reactors, including turbulent reacting flow, quench, and heat transfer.
• Couple detailed and reduced chemical kinetic mechanisms for N2/O2/NOx chemistry to flow solvers to predict NO formation, NO decomposition during cooling, and overall fixation yield.
• Use simulation results to drive the design of reactors, quench sections, and heat recovery equipment that capture high-grade heat while preserving product.
• Develop and reduce kinetic mechanisms as needed, and perform sensitivity and reaction pathway analysis to identify the steps that control yield and energy efficiency.
• Partner with the experimental team to plan diagnostics and test campaigns (temperature, species, and pressure measurements) that validate and calibrate models.
• Conduct conjugate heat transfer, thermal stress, and materials temperature assessments for components exposed to high-temperature, oxidizing gas.
• Translate CFD and kinetics results into design recommendations, technical specifications, and clear documentation for engineering and leadership.
• Establish simulation best practices at Nitricity, including meshing standards, solver settings, verification and validation workflows, and model version control.
• Work with outside engineering firms and software vendors, and help scale models from laboratory and pilot systems to megawatt-scale commercial plants.

• BS in Mechanical, Chemical, or Aerospace Engineering or a related field with 2+ years of relevant experience, or MS, with a focus on fluid mechanics, heat transfer, combustion, or reacting flows.
• Hands-on experience running reacting-flow CFD simulations of high-temperature gas flows using a commercial or open-source package (ANSYS Fluent, STAR-CCM+, CONVERGE, OpenFOAM, or similar).
• Strong grounding in turbulence modeling, turbulence-chemistry interaction, radiation, and heat transfer.
• Working knowledge of chemical kinetics and experience coupling finite-rate chemistry to flow simulations, using tools such as Cantera, CHEMKIN, or equivalent.
• Proficiency with 3D CAD (SolidWorks, Onshape, or similar), including parts, assemblies, and engineering drawings, and preparing geometry and meshes for simulation.
• Working knowledge of GD&T, materials selection, and design for manufacturing for components operating at high temperature.
• Experience validating simulations against experimental data and communicating uncertainty clearly.
• Scripting skills in Python or similar for pre/post-processing, automation, and parametric studies.
• Work well in focused teams with multiple disciplines and thrive in a fast-moving start-up environment.
• Enthusiasm for high-impact, hard tech solutions.

• Proficiency with ANSYS simulation tools (Fluent, CFX, Chemkin-Pro, and/or Mechanical).
• Experience with AI-enabled modeling and simulation workflows, such as machine learning surrogate models, reduced-order models, AI-assisted design optimization, or automated parametric studies.
• Experience with high-temperature air chemistry, NOx formation and destruction (Zeldovich and related mechanisms), plasma-assisted chemistry, or non-equilibrium flows.
• Experience with rapid quench, gas-phase reactor design, or hypersonic and arc-heated flows.
• Experience with mechanism reduction, chemical reactor network modeling, or 0D/1D reactor models alongside full CFD.
• Background designing heat exchangers or heat recovery equipment for industrial processes.
• Familiarity with HPC environments and cloud-based simulation workflows.

• Annual Base Salary $110,000/yr – $150,000/yr
• 3 weeks of paid vacation (accruing)
• Medical and dental insurance
• 401k plan with matching
• Parental leave
• Commuter benefits

*Benefits are subject to change over time and may require employment in CA to be eligible.

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