Characterisation of very high pressure diesel sprays using digital imaging techniques

Injection pressure is one of the most influential factors on the performance of diesel engines and particulate emissions. Car manufacturers have gradually increased this pressure over recent years. The objective of this study is therefore to investigate the effect of injection pressure on the macroscopic spray characteristics for a wide pressure range (up to 250 MPa). For this, we developed a measurement technique able to extract these characteristics both quickly and reliably. The results obtained make it possible to widen the application fields of the temporal evolution law already suggested by some authors and establish new laws for other spray characteristics (angle, area, volume,…).