Multiple injection for improving knock, gaseous and particulate matter emissions in direct injection SI engines

Investigation into ethanol effects on combustion and particle number emissions in a spark-ignition to compression-ignition (SICI) engine

“…For the single injection, except for the severe wall impingement conditions (SOI1 = -310 and -90°CA ATDC), 93#E10 also has the ability to reduce accumulation mode particles. Whatever the number of injection is, both THC and PN deteriorate when the injection timing is too late, which indicates that the injection timing plays a more important role in emissions compared with the number of injection [18].…”

“…In order to further extend knock/lean limit and improve thermal efficiency, several methods, including fuel stratification [17][18][19], hydrogen-alcohols dual-fuel strategy [20][21][22][23] and high-energy spark assistance [7,24], have been used in engines fueling low-carbon alcohols. Han et al [18] compared the influence of injection timing (intake or compression stroke) and number of injections on fuel consumption and emissions using research-grade E10 gasoline. The results showed that the injection timing had more significant influence than the number of injection on knock resistance and gaseous emission reduction because of stratification and charge cooling effect.…”

Split Injection Strategy Optimization to Achieve Ideal Stratified‐Charge Mixture and Reinforce Ultralean Burn in a High Compression Ratio Direct Injection Spark Ignition Engine

“…[ 16 ] Recent research indicated that compared to single injection (SI), split injection could expand the knock limit and increase the indicated thermal efficiency through charge cooling effect and advancing combustion phase. [ 17,18 ] LBC and high compression ratio (CR) are the two main technologies to improve thermal efficiency [ 19–21 ] but the fact that the CR of spark ignition engine is constrained by the knock combustion. Ning et al [ 20 ] investigated the LBC characteristics in a high CR DISI methanol engine and discovered that under λ = 1.4, greater brake thermal efficiency was obtained.…”

Drive Control Experimental Studies on the Injection Characteristics of a Self-Pressurized Injector

“…Stratified injection allows the injection of the minimal fuel amount required to achieve power output or engine speed and has been usually applied to idle, low-engine loads and speeds [38]. The multiple injection strategy may improve the charge composition homogeneity, enhance turbulence, reduce fuel impingement on combustion chamber and piston surfaces, and maximize charge cooling effects [39].…”