Amelia Bruno

Bio:

Amelia (Mia) is a NASA NSTGRO fellow and PhD candidate in the Space Propulsion Lab. She is from East Freetown, MA and received her B.S. in mechanical engineering from UMass Amherst in 2019 and joined MIT SPL in Fall 2019. Mia received her S.M. in 2021 from MIT with her thesis “Design of a Bimodal Chemical-Electrospray Propulsion System using Ionic Liquid Monopropellants.” Her doctorate research focuses on the use of monopropellants (specifically ASCENT propellant) in electrospray thrusters to enable a bimodal chemical-electrospray propulsion system for small spacecraft.

Research Summary:

Two primary propulsion modes currently exist for spacecraft: chemical (e.g. monopropellant, cold gas, solid propellant) and electric (e.g. Hall thruster, ion engine, electrospray). Chemical propulsion typically offers high thrust and low specific impulse, while electric propulsion provides the inverse of low thrust and high specific impulse. As such, having access to both modes on the same spacecraft is extremely useful for a wide range of applications. However, small spacecraft (such as CubeSats) do not have the volume or mass budgets to carry two completely independent propulsion systems onboard, and so are limited to one mode. However, recent advancements in green monopropellants – developed as less-toxic alternatives to hydrazine in chemical monopropellant thrusters – have created a new family of propellants that are also compatible with electric thrusters. In particular, hydroxylammonium nitrate (HAN) based green monopropellants are also ionic liquids, which is the standard propellant for electrospray thrusters. These propellants enable a unique opportunity: a multimodal propulsion system with chemical monopropellant thruster(s) and electrospray thruster(s) that are fed from a shared green monopropellant tank. The objective of this research is to enable a direct application of this technology by investigating the performance of green monopropellants in electrospray thrusters and integrating these thrusters into a flight-ready propulsion system.