Plasma Characterization for Electrothermal-Chemical (ETC) Gun Applications
Final rept., June 93-94
ARMY RESEARCH LAB ABERDEEN PROVING GROUND MD
Pagination or Media Count:
Successful application of the electrothermal chemical ETC propulsion concept will require an understanding of the propagation and interaction of plasmas in propellant beds. This information is necessary to exploit the ignition and combustion control that is possible with plasmas. Toward this end, an experimental program was designed to gain an understanding of the functioning of the plasma and the interaction of the plasma with the propelling charge, and family a series of 30-mm gun tests, incorporating the experience gained in the first two parts of the program, was conducted. This report describes the results of the first two parts of this program. Here results are described of tests on different igniter centercore configurations to be used for distributing the electrical plasma within the combustion chamber. High speed photographic measurements were made of open air firings with various centercore designs and in a 30-mm gun simulator. Propagation velocities along with the time sequence of events for the functioning in the centercore tubes were recorded. High axial pressure gradients were observed, necessitating mechanically robust centercores. Radiation levels substantially in excess of conventional igniters were also noted. These observations were exploited in the design of a plasma distribution centercore for 30-mm gun tests.