Senior Multiphysics Engineer, High Speed Reacting Flow

Anduril Industries is a defense technology company with a mission to transform U.S. and allied military capabilities with advanced technology. By bringing the expertise, technology, and business model of the 21st century’s most innovative companies to the defense industry, Anduril is changing how military systems are designed, built and sold. Anduril’s family of systems is powered by Lattice OS, an AI-powered operating system that turns thousands of data streams into a realtime, 3D command and control center. As the world enters an era of strategic competition, Anduril is committed to bringing cutting-edge autonomy, AI, computer vision, sensor fusion, and networking technology to the military in months, not years.About the Team The Multiphysics Team's work is essential to support our rapid innovation cycle and improve the performance and reliability of advanced defense technologies. Multiphysics Engineers combine computational and experimental methods to size, design, and optimize systems involving complex, coupled physics processes and environments. This team operates with full design ownership through the product development cycle, moving from system-level and first-principles models to 3D simulation and validation/product testing. About the Job We are looking for a Multiphysics Engineer to join our team in Costa Mesa, CA. In this role you will own the internal flow, combustion, and heat transfer analysis behind air vehicle propulsion systems. We are looking for strong fundamentals in compressible flow and heat transfer, and a track record of quickly delivering useful results. What You’ll Do Run CFD analysis of internal and high-speed flows, with and without combustion Start with hand calculations and 1D models to size a design, then move to 3D CFD to refine it Predict heat loads, surface temperatures, and pressures for the thermal and structural teams Set up gas properties and chemistry appropriate to the conditions being modeled Support rocket nozzle, insulation, and case design decisions with analysis Build and document repeatable workflows so other engineers can run the same analysis Compare predictions against static fire and ground test data and improve the models Support material response and erosion analysis in high-temperature environments Work with aerodynamics, thermal, structures, materials, and test engineers Present results at design reviews and document the analysis Required Qualifications Master’s degree in Aerospace engineering, Mechanical Engineering, Chemical Engineering, Engineering Physics, or a related field Ability to obtain and maintain a U.S. secret security clearance 5+ years of experience in CFD, aerothermal, thermal, or combustion analysis Foundational understanding of compressible flow including shocks, choked flow, and supersonic nozzles Strong first-principles understanding of heat transfer and fluid dynamics, including conduction, convection, radiation, fluid flow, and transient thermal behavior Experience with commercial CFD code such as STAR-CCM+, Fluent, or similar, including meshing and driving a case to convergence Proficient in applying hand calculations and 1D models to independently validate CFD results Programming experience in Python, MATLAB, or similar Clear technical writing and the ability to present results to customers Passion for defending the United States and her allies Preferred Qualifications PhD in a related field Active U.S. Secret or Top Secret security clearance Experience with solid rocket motors, propulsion systems, or energetic materials Experience with reacting flow modeling — finite-rate or equilibrium chemistry and species transport Experience with chemistry and gas property tools such as NASA CEA, Cantera, or CHEMKIN Experience selecting solvers and flux schemes for shock-dominated flows Experience with high-temperature or high-enthalpy flow Experience with ablative or charring materials and surface heat transfer Experience with multiphase or particle-laden flow Experience with exhaust plumes, jet interaction, or base flow Experience comparing models against instrumented test data Scripting and automation experience (Python, STAR-CCM+ Java macros, or Fluent journaling and UDFs) Graduate research in aerothermodynamics, combustion, propulsion, or thermal protection materials and systems US Salary Range$146,000—$194,000 USDThe salary range for this role is an estimate based on a wide range of compensation factors, inclusive of base salary only. Actual salary offer may vary based on (but not limited to) work experience, education and/or training, critical skills, and/or business considerations. Highly competitive equity grants are included in the majority of full time offers; and are considered part of Anduril's total compensation package. Additionally, Anduril offers top-tier benefits for full-time employees, including: Benefits At Anduril, we invest in our people. Our comprehensive, competitive benefits package (available at little to no cost to employees) ensures you’re supported in health, recovery, and whatever comes next. For more information, Explore Our Benefits.