CHEMICAL SCAVENGER PROBE DETERMINATIONS OF ATOM AND EXCITED MOLECULE CONCENTRATIONS IN NONEQUILIBRIUM SUPERSONIC STREAMS OF ACTIVE NITROGEN
Abstract
A quartz chemical scavenger probe was developed to study local active species concentrations in a gas expanded from a converging-diverging nozzle glow discharge source. The probe samples a small central portion of the supersonic non-equilibrium jet. Results obtained with active N at one relatively low discharge power output are discussed. The sampled gas mixed and reacted inside the probe with one of the scavenger gases NO, NH3 or C2H4 at 18.8 mm Hg and an average temperature of 500 K. The NO light titration technique and the production of HCN from C2H4 set an upper and lower bound respectively for the atom concentration. The observed maximum amount of NO decomposition was 2.1 times as large as the NO light titration end point flow rate. This difference is far in excess of that observed in conventional discharge flow systems and is interpreted as being due to excited N2 molecules reacting with NO in a reaction slow compared to that between N-atoms and NO. The contribution of these molecules to the energy content of the jet was found to be at least comparable to that of the N-atoms. A new analytical technique for quantitative analysis of the undecomposed NO was developed. Decomposition of NH3 also showed the presence of excited molecules. The NO light titration technique can also be used for composition measurements of the total supersonic jet. (Author) AD-296 3989N4 +++Chemical scavenger probe determinations of atom and excited molecule concentrations in nonequilibrium supersonic streams of active nitrogen.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1962
- Accession Number
- AD0296398
Entities
People
- A. Fontian
- D.e. Rosner
- S.c. Kurzius