Faculty Advisor

Gatsonis, Nikolaos A.


As part of a continuing research effort into the characterization of Pulsed Plasma Thruster (PPT) plumes, this project assisted in ground and space experiments in an effort to help determine thruster performance and plume/spacecraft interaction. This project was performed at NASA Glenn and used a larger vacuum tank than previous projects. Utilizing a motorized experiment mount, Triple Langmuir Probe (TLP) measurements were taken on a plane parallel to the thruster electrodes at a distance of 10 centimeters from the exit plane and angular positions of 90, 75, 60, 45, 30, 20, 10, and 0 degrees from the centerline. Analysis performed at WPI determined electron density and temperature and our results were compared with earlier measurements taken in a smaller tank. Maximum values of electron temperature range from 2.5 to 4 eV and maximum values of electron density range from 6.98 x 10? m? to 6.12 x 10? m?. Data shows a decrease in the maximum electron density as a function of radial position, while electron temperature remains almost constant. This project assisted also in the design of an in-space plume investigation. This joint WPI/MIT shuttle-based experiment is planned to test Hall thrusters and PPT's in a hard vacuum environment. This project concentrated on the design of an articulating boom that will carry Langmuir probes for plume investigation, as well as instrument selection and placement in the backflow region of the thruster.


Worcester Polytechnic Institute

Date Accepted

January 2000

Project Type

Major Qualifying Project


Restricted-WPI community only

Advisor Department

Mechanical Engineering