Design and Development of a Supersonic Nitrogen Gas Flow System for Beamed Microwave Plasma Experiments

Open Access
Brandon, Ashley Marie
Area of Honors:
Aerospace Engineering
Bachelor of Science
Document Type:
Thesis Supervisors:
  • Michael Matthew Micci, Thesis Supervisor
  • Kenneth Steven Brentner, Honors Advisor
  • compressible flow
  • propulsion
  • microwaves
  • plasma
  • converging diverging nozzle
  • beamed energy
The purpose of this experiment is to improve upon a preexisting beamed microwave propulsion system by bringing the exit flow to supersonic speeds. This research builds upon an experiment previously designed at Penn State. The working fluid of this experiment, nitrogen, must be transported from tanks pressurized to 6,000 psig to the chamber of an electric propulsion system. Improving the mass flow rate of the system ensures supersonic flow to the exit of the nozzle and furthers the goal of optimizing the system’s thrust and specific impulse. Increasing the mass flow rate will also eliminate undesirable characteristics that previously manifested in the flow. Both experimental and theoretical calculations revealed the presence of shock waves in the prior experiment, which have substantially impaired the propulsion system’s performance. The improved experimental design increases the effective feed system flow area that follows the nitrogen tank orifice. Further improvements include the addition of a high mass flow rate pressure regulator, an additional two nitrogen tanks, and various safety measures. The results of the experiment demonstrated that the new experimental design eliminated the presence of shocks in the nozzle. Though a chamber pressure of over 900 psig has already been achieved, further experiments are being conducted to test the viability of increasing the chamber pressure to 2,000 psig.