Chemical activity and transport processes in the vicinity of a plasma jet igniter

✍ Scribed by R.M. Clements; P.R. Smy; D. Topham; I.M. Vince; C. Vovelle; F.J. Weinberg

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 540 KB
• Volume: 57
• Category: Article
• ISSN: 0010-2180
• DOI: 10.1016/0010-2180(84)90046-4

✦ Synopsis

Because of the well-known enhancement of combustion observed with plasma jet ignition, various measurements have been carried out upon the subsonic puff of highly turbulent gas ejected from a pulsed plasma jet igniter. "Spot" measurements of temperature show that the puff propagates with a sharp temperature front whose thickness is -10 t mm. Measurements of the flow velocity within the puff reveal that it is approximately equal to the front velocity of the puff and is thus capable of propagating both heat and particles from the igniter to the front of the puff. Finally measurements of the nitric oxide generated at various distances from the igniter when the plug is filled with N2 or 02 and is discharged into a vessel containing the complementary gas show that atomic nitrogen or oxygen is generated in amounts greatly in excess of equilibrium dissociation in a uniformly heated plasma. The production of NO extends several centimeters away from the igniter, where, in view of the low measured gas temperature, it can only be ascribed to the reaction between atomic nitrogen and molecular oxygen (or vice versa). Since such atoms are only created in the plasma within and close to the igniter, we conclude that they survive for appreciable times and distances and that radicals as well as heat are propagated by the internal flow processes.