Radio Frequency Plasma Spark Plug Development and Engine Testing

The Quarter Wave Coaxial Cavity Resonator (QWCCR)
plasma igniter is designed, from requirements drawn
from previous theoretical work, as an ignition source
for an internal combustion engine. The present
research has explored the implementation of the QWCCR
into an IC engine. The QWCCR design parameters of
inner conductor length, loop geometry, and loop
position were varied for two igniters of differing
operating frequency. Variations of the QWCCR RF
parameters as a function of engine geometry were
studied by placing the igniter in a combustion
chamber and manually varying the crank position.
Three identical igniters were fitted with dielectric
inserts and the parameters were studied before and
after ignition was sustained in a Briggs and
Stratton® V-Twin engine. Optimal resonator
geometries were determined. RF parameter invariance
was found with respect to crank angle and piston
distance. The first successful IC engine ignition
using a QWCCR was achieved.