Doctoral Dissertations

Keywords and Phrases

Electrospray; Ionic Liquid Mixtures; Multi Mode; Propellant; Propulsion; Space craft


"In recent years, there has been a dramatic increase in the number of small satellites (namely MicroSats, NanoSats, and CubeSats) in earth orbit; many of these are launched without propulsion systems. Multi-mode propulsion systems, capable of operating in either chemical or electric mode, have been proposed as attractive candidates for use in small satellites. Such systems are mass and volume optimal and flexible in terms of thrust requirements. Most previous work on multi-mode systems has focused on chemical mode performance.The work in this dissertation focuses on the electric mode performance of these propulsion systems.

The work in this research is comprised of three separate but related technical papers, each adding insight into the characterization and design of the electrospray (electric) mode of multi-mode propellant systems. The first paper focuses on determining species in the electrospray plume of a specific propellant, composed of 1-ethyl-3-methylimidazolium ethylsulfate ([Emim][EtSO4]) and hydroxylammonium nitrate (HAN), previously optimized for chemical mode performance. This paper shows HAN, a common energetic component, is present in the plume. The second paper identifies how changes in ionic liquid (IL) mixture ratio affects the species present in the plume and shows clear variations in plume species with mixture ratio for [Emim][EtSO4] and ethylammonium nitrate mixtures. The last paper quantifies how non-linearity in physical properties within IL mixtures impacts propellant performance. Predictions assuming linear mixing of properties over-predict emission current and thrust by up to 45% and 20%, respectively, when compared to calculations based on experimental mixture data"--Abstract, page iv.


Riggins, David W.

Committee Member(s)

Rovey, Joshua L.
Pernicka, Henry J.
Isaac, Kakkattukuzhy M.
Prince, Benjamin


Mechanical and Aerospace Engineering

Degree Name

Ph. D. in Aerospace Engineering


George C. Marshall Space Flight Center
United States. Air Force Office of Scientific Research Nanosatellite Program
Goddard Space Flight Center Undergraduate Student Instrument Project
University of Missouri Fast Track Program


Support for this work was provided through the NASA Marshall Space Flight Center, NASA grant NNM15AA09A, and the Air Force University Nanosatellite Program through the Utah State University Research Foundation, grant CP0039814. Additional support was provided by NASA Goddard Space Flight Center through the NASA Undergraduate Student Instrument Project grant NNX16AI85A, and the University of Missouri System Fast Track Program, FastTrack-16003R.


Missouri University of Science and Technology

Publication Date

Spring 2020

Journal article titles appearing in thesis/dissertation

  • Hydroxylammonium nitrate species in a monopropellant electrospray plume
  • Mass spectrometric investigation of mixtures containing ionic liquids 1-ethyl-3-methyl-imidazolium ethylsulfate and ethylammonium nitrate
  • Effect of nonlinear mixing on electrospray propulsion predictions


xii, 122 pages

Note about bibliography

Includes bibliographic references.


© 2020 Mitchell John Wainwright, All rights reserved.

Document Type

Dissertation - Open Access

File Type




Thesis Number

T 11697

Electronic OCLC #