This study investigated the performance of a natural gas injector with regard to its mass transfer and fuel dispersion. A newly developed gas injector was fabricated with an injector nozzle size that was optimized based on computational fluid dynamics. High-speed injection images were analyzed with the injection parameters related to injection penetration length, injection cone angle, injection time, and injection area. Both λ (the ratio of mass per injection area) and JP(a rate of change of pixel number to change of penetration length) were employed to estimate the quantity and quality of the dispersion. As a result, a uniform distribution and well-dispersed gas properties could be explained with low λ and high JP values. The λ and JP results could be a very useful index used to quantitatively and qualitatively evaluate the performance of natural gas injection.
