Different Measurement Techniques to Determine Hole to Hole Dispersion in a Real Diesel Injector

In the present paper four experimental techniques are used to determine hole to hole dispersion in Diesel injector nozzles. The four methodologies used in the present work are the silicone technique to determine the real internal geometry, mass flow rate measurements of each orifice against ambient pressure, spray momentum flux measured at a constant distance from the nozzle orifice and Spray visualization in high pressure nitrogen ambient conditions. Generally, all these techniques can be used in order to determine the hole to hole dispersion due to different angle inclination of the orifices, different internal geometry, fouling, nozzle needle off-center, etc. The objective of this article is to apply the four methodologies to a real VCO nozzle used for a two valve engine equipped with a common rail fuel injection system.