Experimental Investigation of Diesel Spray Behavior Influenced by Injector Internal Component Modification

Diesel spray characteristics play a crucial role in determining combustion quality, engine performance, and exhaust gas emissions. Previous studies have primarily focused on spray behavior and its influence on combustion using production-type multi-hole diesel injectors. However, the potential for improving engine performance and emission characteristics through modifications to injector internal components has not yet been sufficiently explored. This study experimentally investigates the effects of injector internal component modification on diesel spray characteristics, with the aim of clarifying the relationship between internal injector configuration and spray behavior. Macroscopic high-speed imaging was employed to characterize the temporal evolution of the injected spray, while injection-rate measurements were conducted to evaluate changes in fuel delivery behavior resulting from the internal modification. The analysis focuses on the correlation between injector internal modification and the resulting spray characteristics. The results demonstrate that modification of injector internal components significantly influences diesel spray behavior, particularly during the early stage of injection, through changes in injection-rate development and spray formation processes.