Dynamical modeling and state estimations of gasoline and ethanol impingement sprays in GDI systems using experimental and state space based approaches

Abstract

This study presents a comparative experimental and modeling analysis of the impingement spray characteristics of gasoline and ethanol using a high-pressure gasoline direct injection (GDI) injector. We develop Lyapunov-based approach to estimate key spray characteristics including rebound height with aid of MATLAB-based experimental data processing algorithms, both qualitative and quantitative assessments are provided, as well as a forecast of the state of these characteristics in future time intervals. We present a combined experimental and modeling approach for analyze the impingement spray behavior of gasoline and ethanol using a GDI injector taking into account base experimental results obtained in [3] where macroscopic properties were investigated via high-speed Schlieren imaging and Phase Doppler Particle Analysis (PDPA) across injection pressures ranging from 10 to 50 MPa. Data-driven modeling was supported by MATLABbased polynomial curve fitting and system identification techniques. Key findings reveal that gasoline exhibits superior spray penetration and atomization compared to ethanol, particularly at ultra-high pressures. This suggests that gasoline atomization could significantly enhance combustion efficiency and emissions reduction in GDI engines.