Isolated Low Temperature Heat Release in Spark Ignition Engines

<div class="section abstract"><div class="htmlview paragraph">Low temperature heat release (LTHR) has been of interest to researchers for its potential mitigate knock in spark ignition (SI) engines and control auto-ignition advanced compression (ACI) engines. Previous studies have identified investigated LTHR both ACI SI before the main high (HTHR) event by appropriately curating in-cylinder thermal state during compression, or case engines, timing discharge late reveal (sometimes referred as pre-spark release). In this work, is demonstrated isolation from HTHR events. Tests were run on motored single-cylinder inlet air temperatures pressures adjusted realise n-heptane iso-octane (2,2,4-trimethylpentane) without entering regime. was observed a lean n-heptane-air mixture at ranging 60°C 100°C 0.9 bar (absolute). For below not detected above measurements could be taken due presence HTHR. No same conditions. Following predictions chemical kinetics modelling CHEMKIN (and previous studies), intake increased 1.1 1.5 bar, which successfully led realisation iso-octane. The effect temperature, pressure, engine speed presence, intensity phasing are presented alongside pressure-temperature trajectories gases explain trends.</div></div>