Liquid penetration length in direct diesel fuel injection

We have conducted experimental measurements to estimate the liquid penetration length of a diesel fuel jet injected into an inert environment. We analyzed the effects of the characteristic parameters, i.e., the nozzle diameter, discharge coefficient, injection pressure, and working fluid density. The transient fuel injection process was recorded using optical access, and the liquid penetration length before the second break-up regime was measured using the ombroscopy technique. The experimental data were subsequently fitted to a correlation that accurately predicts liquid penetration length at conditions typical of modern Heavy Duty common rail diesel engines operating with direct fuel injection. A statistical analysis of our experimental measurements suggests a power function correlation to model the liquid penetration length. The proposed model is in good agreement with experimental data and yields a correlation coefficient R2 = 93.3%. It is expected that this correlation can be of assistance in the successful designing of combustion chambers required by modern heavy duty diesel engines.