Eric T. Wolf

Date of Award


Document Type


Degree Name

Master of Science


Department of Aeronautics and Astronautics

First Advisor

David Liu, PhD.


This research focuses on experimentally characterizing the performance parameters of a colloid thruster with porous emitters through optical techniques. Porous emitters are different than traditional needle emitters in how they allow a variation in the number and size of Taylor Cones throughout a range of propellant volumetric flow rate conditions. An algorithm is created to calculate the estimated minimum and maximum number of emitter sites based on magnified images of the porous emitter heads. Theoretical thruster performance parameters are then established from the estimated number of emitter sites. Experimental techniques for measuring the thrust and exhaust exit velocity are proposed. They are then analyzed for their compatibility and limitations with colloid thruster testing based on the theoretical performance parameters. The research and analysis lays the foundation for future colloid thruster testing and characterization. This baseline model and analysis can be refined through laboratory testing in order to be used for future mission analysis determining the viability of the new porous emitter as an enhanced colloid thruster feature over traditional needles.

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DTIC Accession Number