Research Engineer, Aerosol & Liquid Dispersion Systems

Rainmaker is pioneering a modern cloud seeding system to solve water scarcity and inclement weather problems. We develop and incorporate radar validation, weather-resistant UAS, numerical weather modeling, and sustainable cloud seeds into an effective precipitation enhancement solution. The Engineering team at Rainmaker works on our UAS, dispersion payload, and in-situ/remote sensing systems. If you are interested in working in an extremely innovative and fast-paced environment, where your work directly makes an impact and difference in our operational system, this is a fantastic opportunity.   About the Role We are seeking a highly hands-on Mechanical/Aerospace Research Engineer with deep expertise in aerosol science, multiphase flow, and compressible fluid dynamics. In this role, you will bridge the gap between cloud physics and high-performance fluid systems, designing hardware that utilizes high-velocity gas dynamics to both fragment nanoparticle agglomerates and atomize liquid precursors into submicron aerosols. You will tackle complex mechanical challenges to efficiently disperse cohesive dry powders and ultra-fine droplets, managing complex mass-transfer and particle/droplet momentum while strictly adhering to aerospace SWaP (Size, Weight, and Power) constraints.   Key Responsibilities High-Velocity Nozzle Design: Design, machine, and test custom Convergent-Divergent (Laval) nozzles to achieve controlled gas expansion for both liquid filament breakup and high-shear solid deagglomeration. Multiphase Dispersion: Develop and optimize systems for the simultaneous or alternating dispersion of complex liquid aerosols and dry-powder "seeds" using high-velocity gas streams. Hardware Prototyping: Build mechanical dry-powder micro-feeders, liquid delivery architectures, and aerosol generators from the ground up, utilizing high-pressure gas supply systems. Fluid/Mechanical Architecture: Develop the pneumatic and fluidic routing systems (valves, regulators, and micro-channels) required to maintain specific pressure ratios necessary for choked flow and stable supersonic jets. UAS Integration: Adapt benchtop aerosol generation concepts into lightweight, battery-efficient payloads capable of surviving flight vibrations and high aerodynamic shear. Rapid Iteration: Work collaboratively to evaluate hardware performance and rapidly iterate nozzle geometries based on empirical droplet-size and particle-size data.   Required Qualifications BS, MS, or PhD in Mechanical Engineering, Chemical Engineering, or a closely related technical field. Approximately 5 years of hands-on experience in mechanical engineering, specifically focused on fluid dynamics, multiphase flow (gas-liquid/gas-solid), or atomization. Proven experience in Mach number optimization, internal nozzle flow, and the physics of choked flow conditions. Proven experience physically building and troubleshooting fluidic or pneumatic hardware (e.g., high-velocity gas jets, Laval nozzles, precision sprayers, or powder dispersers). Understanding of droplet dynamics and breakup regimes (e.g., Weber number effects) and techniques for nanoparticle deagglomeration. Strong CAD proficiency (SolidWorks, Fusion 360, etc.) and hands-on hardware prototyping experience, including CNC machining and general fabrication.   Preferred / Bonus Qualifications High-Speed Flow Characterization: Experience with the analysis of high-velocity particulate exhaust, liquid-jet disintegration, or supersonic multiphase flows. Advanced Particle & Droplet Dispersion: Familiarity with kinetic aerosolization techniques where liquid or solid phases are accelerated to high velocities for fragmentation or dispersion. Computational Modeling: Experience with CFD (e.g., ANSYS Fluent, COMSOL) to model droplet/particle trajectories, velocity lag, and shock-wave interactions in high-speed plumes. Aerosol Instrumentation: Familiarity with standard analytical tools such as Malvern Spraytec, SMPS, or optical particle counters for characterizing both sub-micron liquid and solid aerosols. Basic proficiency in electronics prototyping (Arduino, Raspberry Pi) and software/scripting (Python) for hardware control and data acquisition.