Research Engineer, Aerosol & Liquid Dispersion Systems

About the role

This role owns the end-to-end design and validation of high-velocity fluidic systems that turn liquid precursors and dry nanoparticles into controlled submicron aerosols for cloud seeding applications. You will own the mechanical architecture that balances extreme fluid dynamics with strict aerospace size, weight, and power constraints. The position owns the hands-on prototyping of nozzles, feed systems, and dispersion hardware from initial CAD models to bench and flight-qualified testing. You will bridge cloud physics with hardware engineering to solve fragmentation and atomization challenges under demanding operational conditions. The hire will directly contribute to building the core dispersion payload that defines Rainmaker's modern cloud seeding system. You will collaborate across engineering disciplines to iterate hardware rapidly and ensure reliability in the field. This role owns problems from first-principles fluid mechanics to final system integration on UAS platforms.

Key facts

What you'll do

• Design high-velocity convergent-divergent nozzles that control gas expansion for liquid filament breakup and solid deagglomeration.
• Develop multiphase dispersion systems that handle simultaneous or alternating flows of complex liquid aerosols and dry-powder seeds using high-velocity gas streams.
• Prototype mechanical dry-powder micro-feeders, liquid delivery architectures, and aerosol generators from the ground up using high-pressure gas supply systems.
• Engineer pneumatic and fluidic routing including valves, regulators, and micro-channels to sustain specific pressure ratios for choked flow and stable supersonic jets.
• Adapt benchtop aerosol generation concepts into lightweight, battery-efficient UAS payloads that survive flight vibrations and high aerodynamic shear.
• Rapidly evaluate hardware performance and iterate nozzle geometries based on empirical droplet-size and particle-size data.
• Apply deep knowledge of Mach number optimization, internal nozzle flow, and choked flow physics to guide mechanical decisions.
• Build and troubleshoot fluidic and pneumatic hardware such as high-velocity gas jets, Laval nozzles, precision sprayers, and powder dispersers.
• Utilize strong CAD proficiency in SolidWorks or Fusion 360 alongside hands-on fabrication skills like CNC machining and general fabrication.
• Understand droplet dynamics and breakup regimes, including Weber number effects, to manage nanoparticle deagglomeration effectively.

Requirements

• Hold a BS, MS, or PhD in Mechanical Engineering, Chemical Engineering, or a closely related technical field.
• Bring approximately 5 years of hands-on mechanical engineering experience focused on fluid dynamics, multiphase flow (gas-liquid/gas-solid), or atomization.
• Demonstrate proven experience in Mach number optimization, internal nozzle flow, and the physics of choked flow conditions.
• Show a track record of physically building and troubleshooting fluidic or pneumatic hardware such as high-velocity gas jets, Laval nozzles, precision sprayers, or powder dispersers.
• Possess a strong understanding of droplet dynamics and breakup regimes, including techniques for nanoparticle deagglomeration.
• Show strong CAD proficiency using tools such as SolidWorks or Fusion 360, combined with hands-on hardware prototyping experience.
• Have practical experience with CNC machining and general fabrication methods to turn designs into physical hardware.
• Operate effectively in a fast-paced, extremely innovative environment where work directly impacts operational systems.

Nice to have

• Experience with high-speed flow characterization, including analysis of high-velocity particulate exhaust, liquid-jet disintegration, or supersonic multiphase flows.
• Familiarity with advanced particle and droplet dispersion techniques, especially kinetic aerosolization where liquid or solid phases are accelerated to high velocities for fragmentation or dispersion.
• Background in computational modeling using CFD tools such as ANSYS Fluent or COMSOL to model droplet and particle trajectories, velocity lag, and shock-wave interactions in high-speed plumes.
• Knowledge of aerosol instrumentation such as Malvern Spraytec, SMPS, or optical particle counters for characterizing sub-micron liquid and solid aerosols.
• Basic proficiency in electronics prototyping with Arduino or Raspberry Pi and scripting in Python for hardware control and data acquisition.

Practical notes

• This is a full-time position based in El Segundo, California.
• Rainmaker participates in E-Verify; more information is available at e-verify.gov.
• Employment with Rainmaker is governed by merit, competence, and qualifications without regard to race, color, religion, gender, national origin, ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability, or any other legally protected status.