Experimental study of the effect of high temperature on vaporization spray characteristics under GCI engine conditions

This paper presents an experimental investigation into the vaporization spray process to examine spray characteristics in the CVCC system under simulated gasoline compression ignition (GCI) engine conditions. The study focuses on understanding the impact of high ambient temperatures on the spray behavior. Vaporization characteristics of a single-hole injector were analyzed across a range of injection pressures (50-80-110 MPa) and utilizing two fuel types, GB20 and GB40. High-speed Schlieren photography captured images of the spray, revealing distinct liquid and vapor phases. Notably, the distinction between liquid and vapor phases becomes more pronounced at elevated temperatures of 800 K and 1000 K, with a constant oxygen concentration of 0 %. Liquid penetration length decreases with rising temperatures across all injection pressure levels. Experimental observations demonstrate rapid expansion of the vaporization zone as temperature increases from 600 K to 1000 K. GB40 images show broader liquid distribution compared to GB20, suggesting more intricate fuel dispersion in the vapor phase. These findings provide crucial insights for theoretical and phenomenological investigations into air-fuel mixing conditions in GCI engine operation, laying a foundation for future research in this domain.