David Liu

Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Aeronautics and Astronautics

First Advisor

Richard Branam, PhD.


The Hall thruster is a type of electric propulsion utilized by satellites to perform a wide variety of missions ranging from station keeping, orbital maneuvers, and even deep space propulsion. In order to accommodate the multitude of missions it also has a wide assortment of sizes and power configurations which can range from approximately an inch in diameter at 20 W to a couple of feet in diameter at 1.5 kW. Additionally, this electro-static device provides high specific impulse without the added weight penalty associated with conventional chemical thrusters. It supplies this high specific impulse by ionizing a gas such as xenon or krypton and then accelerating it through the electric field to speeds on the order of kilometers per second depending on the thruster size and power. Although the steady-state outputs such as thrust and specific impulse are measurable, other transient mechanisms within the main discharge are still not well understood.

AFIT Designator


DTIC Accession Number



David Liu is a 2019 recipient of AFIT's Young Alumni Award, established to recognize alumni who have made outstanding contributions in their career within 10 years of graduating from AFIT. The award recognizes the exceptional professional accomplishments in their professional life, community affairs, and support of the advancement and continued excellence of AFIT.