The morphology and collapsing behavior of fuel sprays play a critical role in determining atomization and vaporization characteristics, directly influencing combustion efficiency and emission formation in direct injection systems. In this study, spray dynamics and collapsing processes of methanol and gasoline fuels were examined using a lateral-cylinder-mounted direct injection (DI) injector in a constant volume combustion chamber (CVCC). A tomographic imaging technique was applied to analyze the spatial and temporal characteristics of fuel sprays. Extinction imaging was performed to capture the distribution of droplets within the spray, and the liquid volume fraction (LVF) was quantified based on the Beer-Lambert law. By acquiring extinction images from multiple viewing angles, 3D tomographic reconstructions of the spray morphology were achieved, providing detailed insights into the structural evolution of the sprays during injection.
The high latent heat of vaporization of methanol significantly influences the spray morphology and plume dynamics, potentially resulting in distinct behaviors compared to gasoline under identical injection conditions. These differences are expected to manifest in the droplet evaporation rates, plume expansion patterns, and overall spray stability. The 3D tomographic reconstruction method provides a detailed visualization of these phenomena, offering valuable insights into how methanol’s thermophysical properties impact spray characteristics and plume collapse tendencies.
This research highlights how methanol’s unique properties influence spray behavior, paving the way for optimized injection strategies and alternative fuel integration. These findings can serve as a foundation for future studies exploring the adaptation of direct injection systems to sustainable fuel applications.