Cycle-to-Cycle Variation Study of an SI Engine Fired by Spark Plug and a Non Conventional Device

Abstract

<div class="htmlview paragraph">This paper reports on an experimental investigation of an SI single cylinder engine cycle-to-cycle variations. Two different ignition devices are studied: a spark plug and a non conventional ignition device, PJC (<u>P</u>ulsed <u>J</u>et <u>C</u>ombustion).</div> <div class="htmlview paragraph">In-cylinder pressure is analyzed via a complete heat release rate computation.</div> <div class="htmlview paragraph">A significant decrease in IMEP cycle-to-cycle variations can be achieved only when the initial burning rate is enhanced with PJC device for example. The cycle-to-cycle combustion variations (CA01, PMax, IMEP) are not improved in the same proportions.</div> <div class="htmlview paragraph">The PJC is a firing device which meets the objective of repeatable ultra-lean mixture ignition and development of combustion, but slightly lowers the global efficiency due to the increase of heat losses for high load running points.</div>