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In order to study differences between Diesel nozzle holes, four methodologies have been tested. The techniques compared in this paper are: the internal geometry determination, hole to hole mass flow measurement, spray momentum flux and macroscopic spray visualization. The first one is capable of obtaining the internal geometry of each of the orifice of the nozzle; the second one is capable of measuring the mass flow of each nozzle hole in both, continuous and real injections. The third one gives the momentum flux of each orifice, and finally, with the macroscopic spray visualization, the spray penetration and spray cone angle of each hole, are obtained. Generally, all these techniques can be used in order to determine the hole to hole dispersion due to different angle inclination of the holes, different internal geometry of orifices, deposits, nozzle needle off-center, needle deflection, etc.

The objective of this work is to make an analysis of the behaviour of the venturi in real working conditions. The modelling of the venturi, as well as the experimental and modelled results obtained, will be described. Modelled and measured techniques have been used to realize this work. A new model of the venturi was developed and using this, it is possible to find important instantaneous variables of the venturi. In order to adjust the calculated model, it was necessary to characterise the steady flow test rig of the venturi. In addition, the information obtained from the engine tests has been essential to correctly adjust the model. Therefore, a combination of the information obtained from both the venturi test and from modelled work was necessary in order to understand the behaviour of the venturi installed in an engine. Different tests have been performed on each venturi.