PR-360-08207-R01 Cylinder Level Sensing and Control on Typical Pipeline Engines

Further reductions in NOx emissions while maintaining optimum engine performance can only be obtained by improving engine combustion control at the cylinder level. This requires cylinder level sensors capable of continuously monitoring combustion performance in both the main combustion chamber (MCC) and the pre-combustion chamber (PCC) and electronically actuated valves that can respond to those measurements. Until recently, in-PCC combustion measurements on spark ignited engines were only possible in the laboratory using very expensive pressure sensors with extremely short lives. Ion Sense offers a non-intrusive, robust and cost effective method to monitor in-PCC combustion in the field on a continuous basis. Derived from automotive technology, ion sense utilizes post ignition ionization measurements from a standard spark plug. When measured from a spark plug mounted in a PCC Ion Sense provides a wealth of previously unavailable information on misfire, instability, flame initiation, early flame propagation, in PCC air/fuel ratio, etc. This work investigated the use of ion sense data collected in the PCC to monitor and control in PCC air/fuel ratio, main chamber air/fuel ratio and the timing of combustion events in both. This paper reports on the results of this testing as well as describing the optimization strategy developed which is applicable to the full range of pipeline engines.