A Synergic Application of High-Oxygenated E-Fuels and New Bowl Designs for Low Soot Emissions: An Optical Analysis

Abstract

Synthetic fuels significantly reduce pollutant emissions and the carbon footprint of ICE applications. Among these fuels, oxymethylene dimethyl ethers (OMEX) are an excellent candidate to entirely or partially replace conventional fuels in compression ignition (CI) engines due to their attractive properties. The very low soot particle formation tendency allows the decoupling of the soot-NOX trade-off in CI engines. In addition, innovative piston geometries have the potential to reduce soot formation inside the cylinder in the late combustion stage. This work aims to analyze the potential of combining OMEX with an innovative piston geometry to reduce soot formation inside the cylinder. In this way, several blends of OMEX-Diesel were tested using a radial-lips bowl geometry and a conventional reentrant bowl. Tests were conducted in an optically accessible engine under simulated EGR conditions, reducing the in-cylinder oxygen content. For this purpose, 2-colour pyrometry and high-speed excited state hydroxyl chemiluminescence techniques were applied to trace the in-cylinder soot formation and oxidation processes. The results confirm that increasing OMEX in Diesel improves the in-cylinder soot reduction under low oxygen conditions for both piston geometries. Moreover, using radial lips bowl geometry significantly improves the soot reduction, from 17% using neat Diesel to 70% less at the highest OMEX quantity studied in this paper.

Analysis of Particle Number Emissions in a Retrofitted Heavy Duty-Spark Ignition Engine Powered by LPG

“…The automotive industry has adapted to legislative requirements and developed various strategies to minimize the environmental impact of propulsion systems. These strategies include optimizing fuel injection [6] and air management systems [7], using pre-chamber devices [8], and introducing innovative piston geometries [9] to reduce pollutant formation. Despite the success of 2 these measures in lowering emissions, stringent emission thresholds necessitate the use of advanced Aftertreatment Systems (ATS) [10] to meet regulatory limits before exhaust gases are released into the environment.…”

Investigating Spray Characteristics of Synthetic Fuels: Comparative Analysis with Gasoline

“…However, there have been many studies on synthetic fuels. Pastor et al [13] shared an investigation of oxymethylene dimethyl ethers (OME) when blended with diesel in an optical engine setup. Their findings unveiled enhanced in-cylinder soot reduction, particularly evident under low oxygen conditions, with varying piston geometries.…”

Analysis of Particle Number Emissions in a Retrofitted Heavy-Duty Spark Ignition Engine Powered by LPG

“…In response, the automotive industry has adapted to legislative requirements and developed various strategies to minimize the environmental impact of propulsion systems as a response to the standards implemented worldwide to reduce pollutant emissions. These strategies include optimizing fuel injection [9] and air management systems [10], using pre-chamber devices [11], introducing innovative piston geometries [12], and applying zero-dimensional models of the combustion process [13] to reduce pollutant formation. Despite the success of these measures in lowering emissions, stringent emission thresholds necessitate the use of advanced aftertreatment systems (ATS) to meet regulatory limits before exhaust gases are released into the environment [14].…”