Standardized Gasoline Compression Ignition Fuels Matrix

Abstract

Direct injection compression ignition engines running on gasolinelike fuels have been considered an attractive alternative to traditional spark ignition and diesel engines. The compression and lean combustion mode direct injection of fuel eliminates throttle losses yielding higher thermodynamic efficiencies and the better mixing of fuel/air due to the longer ignition delay times of the gasoline-like fuels allows better emission performance such as nitric oxides (NOx) and particulate matter (PM). These gasoline-like fuels which usually have lower octane compared to market gasoline have has been identified as a viable option for the gasoline compression ignition (GCI) engine applications due to its lower reactivity and lighter evaporation longer ignition delay characteristics compared to diesel and lighter evaporation compared to gasoline fuel. The properties, specifications and sources of these GCI fuels are not fully understood yet because this technology is relatively new. In this work, a GCI fuel matrix is being developed based on the significance of certain physical and chemical properties in GCI engine operation. Those properties were chosen to be density, temperature at 90 volume % evaporation (T90) or final boiling point (FBP) and research octane number (RON) and the ranges of these properties were determined from the data reported in literature. These proposed fuels were theoretically formulated, while applying realistic constraints, using species present in real refinery streams gasoline-like fuels. Finally, three-dimensional (3D) engine computational fluid dynamics (CFD) simulations were performed for using the proposed GCI fuels and the similarities and differences were highlighted.

Auto-ignition of direct injection spray of light naphtha, primary reference fuels, gasoline and gasoline surrogate

“…These richer pockets cause the ignition delay times to be shorter than those of PRF65. This finding is in agreement to what was recently observed in engine simulations and experiments using LN and PRF65 surrogate [52][53][54]. PRF 65 has significantly higher reactivity compared to the gasoline fuel and its multi-component surrogate, however, it has longer ignition delay times at low temperatures (Fig.…”

“…These correspond to the shortest and longest reported ignition delay times at 650 K for LN and PRF95, respectively. However, the ignition delay times cannot be explained by only looking at the ON (or AKI) because the gasoline fuel and its surrogate have similar AKI but different ignition delay times at 650 K. The equivalence ratio-temperature distribution is a key determining factor in compression-ignition engines [51][52][53][54] and like any compression-ignition combustion system, the ignition delay times of reacting sprays are dependent on the local temperature and equivalence ratio distribution in the constant volume combustion chamber.…”

Development of a reduced four-component (toluene/n-heptane/iso-octane/ethanol) gasoline surrogate model

“…A single cylinder 4 valve engine with a 16:1 volumetric compression ratio (CR) is used in this investigation. Table 1 shows the details of the engine specifications and more details about the engine can be found in [43,44]. A new set of CR 16 piston was designed and used here to accommodate the PPC combustion strategy using a commercial gasoline with research octane number (RON) of 91.…”

Engine Combustion System Optimization Using Computational Fluid Dynamics and Machine Learning: A Methodological Approach

“…Better mixing of fuel and air prior to combustion (due to the higher volatility of gasoline) reduces soot production relative to the conventional mixing-controlled (diesel) combustion. Our research group in Saudi Aramco extensively investigated the combustion of various fuels in GCI engines [27][28][29][30][31][32][33][34][35][36][37][38][39].…”