STORED CHEMICAL ENERGY PROPULSION SYSTEM (SCEPS) REACTOR INJECTOR PERFORMANCE PREDICTION MODELING WITH EXPERIMENTAL VALIDATION

Open Access
Author:
Crouse, Michael Edward
Graduate Program:
Mechanical Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
July 10, 2017
Committee Members:
  • Dr. Laura Pauley, Thesis Advisor
  • Dr. Stephen Lynch, Committee Member
Keywords:
  • Compressible Flow
  • Fanno Line Flow
  • Rayleigh Line Flow
  • Converging Nozzle
  • Diverging Nozzle
  • Friction
  • Heat Transfer
Abstract:
A quasi one-dimensional compressible-flow model has been developed to characterize the thermodynamic state of gas injectors within stored chemical energy propulsion systems (SCEPS). SCEPS take the form of a batch reactor with a metal fuel and gaseous oxidant. The result is a high-heat, molten metal bath with a reacting gas jet under vacuum pressure conditions. The developed model incorporates the combined effects of Fanno (frictional) and Rayleigh (heat) flow, including entropic predictions of sonic flow conditions. Constant, converging, and diverging-area, Reynolds-scaled nozzle profiles were exercised to demonstrate the capability of the model in forecasting varied flow regimes that may occur in SCEPS injectors. Physical nozzles, with identical geometric profiles to those of the model cases, were then tested for these nozzle conditions in order that the fidelity of the model could be evaluated. The test results validated the model’s static pressure prediction for each nozzle case by producing the same distribution of pressures on the same order of magnitude. The order of temperature values was also validated, although greater divergence from the model predictions occurred toward the latter half of each nozzle. Overall, the model proved to be capable of approximating the same general flow characteristics as those measured in the nozzles of the same case. The model also confirmed that a combined Fanno-Rayleigh entropy curve was instructive in determining sonic flow conditions in each nozzle case. The results of this study demonstrate that the developed model is a feasible tool for fundamental analysis of SCEPS injectors.