Abstract
Multiple injection often come to use for post injection, and the injection quantity per injection is small-quantity. Therefore, it is thought that Spray characteristics in post injection are different from that in main injection. This is important to comprehend the characteristics of small-quantity spray such as post injection. This report, the characteristics of small-quantity spray was obtained from various spray measurement. As a result, small-quantity spray was greatly affected by sheet throttle due to low needle lift movement. Therefore, Sack pressure (Psac) tended to be equal regardless of the Rail pressure (Prail). Also, it is influenced by acceleration of atomization due to an increase in Sac pressure under the injection quantity assumed to be used in post injection. For this reason, it was found that there is a region in which the spray tip penetration is suppressed.
