Observation of Behavior of Post-injected Fuel Film Using Photochromism Visualization Technique

Abstract

The visualization experiments of fuel film attached on the cylinder liner associated with post-injection were conducted by applying the photochromic visualization technique to the optical diesel engine under motoring operation. It was confirmed that the thickness of the lubricating oil film became extremely thin at the area where the fuel impacted with post-injection, while the fuel oil film became thicker. It was also confirmed that the fuel oil film on the liner was scraped by the top ring and moved to the piston land.