Comparison of Different Techniques for Characterizing the Diesel Injector Internal Dimensions

Abstract

The geometry of certain parts of diesel injectors is key to the injection, atomization and fuel-air mixing phenomena. Small variations on the geometrical parameters may have a strong influence on the aforementioned processes. Thus, OEMs need to assess their manufacturing tolerances, whereas researchers in the field (both experimentalists and modelers) rely on the accuracy of a certain metrology technique for their studies. In the current paper, an investigation of the capability of different experimental techniques to determine the geometry of a modern diesel fuel injector has been performed. For this purpose, three main elements of the injector have been evaluated: the control volume inlet and outlet orifices, together with the nozzle orifices. While the direct observation of the samples through an

Computational assessment of temperature variations through calibrated orifices subjected to high pressure drops: Application to diesel injection nozzles

“…The dimensions based on this image are measured by an auxiliary CAD software. The deviation over the mean value has been reported to be below 2% [24]. The most critical part of the whole orifice is the throat, where pressure and velocity gradients are significantly strong.…”