Experimental and analytical study on liquid and vapor penetration of high-reactivity gasoline using a high-pressure gasoline multi-hole injector

Abstract

Penetration lengths for high-pressure GCI injector and GCI fuel were studied. • Liquid penetration length was longer under high EGR condition. • Penetration length regression models showed good agreement with experiments. A R T I C L E I N F O Keywords:Fuel spray High reactivity fuel Penetration correlation Liquid and vapor phase A B S T R A C T Spray penetration length is an important parameter which is of great interest to both experimentalists and modelers. As it affects engine efficiency and emissions, measurement and prediction of spray penetration can significantly benefit engine optimization under various operating conditions. In this study, penetration length was investigated in a pre-burn constant volume combustion chamber using a gasoline multi-hole injector with high reactivity gasoline-like fuel designed explicitly for gasoline compression ignition (GCI) engines. Diffused back illumination (DBI) and shadowgraph were implemented for liquid and vapor phase penetration measurements, respectively. Different pre-burn gas mixtures are compared to investigate the influence of ambient gas properties on gasoline spray penetration under evaporating conditions. The liquid penetration under the gas composition of higher molecular weight tends to be longer. However, the vapor penetration showed insignificant effect under different gas compositions. Ambient gas temperature and gas composition were found to be an essential parameter for liquid phase penetration. Pressure difference was found to affect the vapor penetration length while its influence on liquid phase steady state penetration length at high ambient gas temperature is marginal. Statistical analysis was performed for both liquid and vapor phase penetration lengths, and a prediction model was developed with good agreement to the data under all test conditions.

First Study on Ammonia Spray Characteristics with a Current GDI Engine Injector

“…The exponent coefficients, a f , b f and c f , which are only fuel dependent, were obtained by using an error minimization routine, but the linear coefficients a(t) and b(t) are time-dependent. Nevertheless, the correlations found in literature have only one time dependence as the correlation find by Du et al [30], therefore, the influence of the timedependent parameter b(t) is investigated in this part. In the first case, the correlation is expressed with the two time-dependent parameters, the continuous line in Figure 14, and in the second case, the second time dependence is neglected, the dashed line in Figure 14.…”

“…Recently, Payri et al [25] successfully explored a theoretical approach based on momentum flux conservation along the spray axis for diesel. Du et al [30] expressed the diesel spray penetration as k•(∆P) a •t b with a unique time dependence. These studies have made a significant contribution to our understanding of diesel spray, but flash boiling was not investigated.…”

Auto-ignition characteristics of high-reactivity gasoline fuel using a gasoline multi-hole injector

“…Wang et al [17] studied the auto-ignition of naphtha, primary reference fuels (PRF), gasoline, and its surrogate and found out that ignition delay difference is more significant if the ambient temperature was below 750 K and the difference becomes insignificant when the ambient temperature was above 750 K. Recently, the spray characterization of this GCI RON 77 fuel in comparison with that of certification E10 gasoline fuel was reported. Both the fuels showed very similar liquid and vapor penetration under no EGR to high EGR conditions [18,19]. Further, the fundamental experimental data on fuel spray combustion processes are essential for chemical mechanism development and validating numerical simulations [20].…”

Study of the Gasoline Direct Injection Process under Novel Operating Conditions

“…It has to provide repeatable spray pattern for all flow and pressure conditions in the chamber. This approach presents the highest theoretical efficiency and it is still researched today for new combustion concepts [42,[44][45][46][47][48][49]. It has some advantages respect to the previous systems: wider stratified operation region, less sensitive to in cylinder flow variation, decreased wall wetting, and reduced HC emissions.…”

“…Single-pass Schlieren is a widely known optical technique used by researchers to study gasoline and diesel macroscopic parameters such as vapor phase spray angle and spray penetration [2,21,32,[45][46][47][48]. These parameters are useful, since in addition to revealing behaviors in the phenomena, they are also necessary to validate numerical studies.…”