Effects of Airstream Mach Number on H/N Plasma Igniter

Experimental study of the plasma igniter was conducted in nonheated high-speed air stream. The effects of the Mach number, from 0.9 to 2.4, and the stagnation pressure of the airstream, from 64 to 100 kPa, as well as the hydrogen fraction in the H 2 /N 2 feedstock of the torch, from 0 to 50%, were investigated. In the higher Mach number airstream, more input power to the torch was required to ignite hydrogen fuel. The stagnation pressure of the airstream had complicated effects relating to chemistry and aerodynamics. Improvement of ignition performance due to the increased hydrogen fraction in the feedstock was well correlated with the sum of the electric input energy and the heat of combustion of the hydrogen fed as the feedstock of the torch.