Digital-Imaging-Based Measurement of Diesel Spray Characteristics

This paper presents the application of a direct photographic imaging and image processing system in the quantitative characterization of diesel sprays. A high-resolution charge-coupled device (CCD) camera with a flashlight source is use to capture images of sprays in an optically accessible constant-volume chamber. A set of macroscopic characteristic parameters of the sprays, including tip penetration, near- and far-field angles, spray-tip velocity, and average fuel area density, is derived from the images. Experimental work was undertaken on a common rail fuel injection rig. The relationships between the spray characteristics and the corresponding injection conditions are presented and discussed.