|MIT Department: Aeronautics and Astronautics
Faculty Mentor: Prof. Paulo Lozano
Undergraduate Institution: University of Missouri, Columbia
My name is Ymbar I. Polanco Pino and I am a rising senior at the University of Missouri-Columbia studying mechanical and aerospace engineering. I am originally from Maracay, Venezuela, but I have lived the majority of my life in the Atlanta, Georgia area and Southwest Missouri. My undergraduate research experience has focused on renewable energy technologies, such as piezoelectric energy harvest, and fluid dynamics in a zero gravity environment. The goal is to use my understanding in engineering to promote sustainability in the field of aeronautics and astronautics. I hope to obtain my PhD and use my experiences as a researcher and innovator to serve marginalized communities in the United States and around the world while advancing our society towards environmental sustainability. During my leisure time, I like to make music, play sports, and read.
Neutralization of Monopolar Electrospray Propulsion System via Low-Earth Orbit Plasma Environment
Ymbar Polanco Pino, Oliver Jia-Richards, and Paulo Lozano
Typical electric propulsion systems emit positively charged ions and require the use of a neutralizer that emits electrons in order to maintain spacecraft charge neutrality. For small spacecraft on the CubeSat scale and smaller, the operation of both a propulsion system and its neutralizer can impose significant requirements on the power system that can limit the overall capability of the spacecraft. However, in low-Earth orbit the surrounding atmospheric plasma environment could be used to neutralize the spacecraft thereby eliminating the need for a neutralizer. The neutralizing species from the surrounding plasma environment will depend on the polarity of ions emitted by the propulsion system; a system that emits positive ions will require a flux of positive ions from the plasma environment while a system that emits negative ions will require a flux of electrons. Due to the greater mobility of electrons relative to ions, a propulsion system that emits negative ions will be able to emit far greater current without charging the parent spacecraft. This work analyzes the feasibility of using an ionic-liquid electrospray thruster emitting negative ions for propulsion of a small spacecraft in low-Earth orbit. A theoretical assessment of the maximum expected electron current at different solar activities is provided in order to determine the maximum thrust output of the propulsion system while avoiding spacecraft charging. An experimental validation of the concept is conducted in a vacuum environment in order to demonstrate that a monopolar propulsion system can produce thrust without the need for a neutralizer. The use of such a system could reduce the overall power requirements of propulsion systems for small spacecraft and improve their capabilities in order to enable more-affordable access to space.