Practical delay modeling of externally recirculated burned gas fraction for Spark-Ignited engines

Abstract : This paper studies the low-pressure burned gas recirculation in spark-ignited engines and shows, at the light of supportive experimental results, that a linear delay system permits to capture the dominant effects of the system dynamics. The modeled transport delay is defined by implicit equations stemming from first principles. This model is shown to be sufficiently accurate to replace a sensor that would be difficult and costly to implement on commercial engines.