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We present an extensive experimental study focused on understanding the impact of cavitation in a high-pressure diesel nozzle on the macroscopic properties of fuel spray. Several high-speed videos of the liquid flow through a transparent, asymmetric cylindrical nozzle with a single orifice (phi = 0.35 mm) are recorded along with the videos of the resulting spray in the near-nozzle region, issued with an injection pressure of 300 bar at a frame-rate of 75 kHz. The high-repetition images of the internal flow are then used to estimate the onset of cavitation inside the transparent nozzle and the probability of development of cavitation in different regions of the nozzle with an average estimate of the amount of cavitation with time. On the other hand, recorded spray images are used to study spray penetration, cone-angles and velocity from the start of fuel injection. A novel approach is proposed for the measurement of perturbations that occur in form of big liquid structures along the spray boundary., in 27th European Conference on Liquid Atomization and Spray Systems, Sep 2016, Brighton, United Kingdom. 2016

International audience; Common rail injection system has been developed to increase diesel engine performances and to reduce noise, emission and fuel consumption. Such goals are possible only if the whole system is perfectly controlled. But, any system component failure can lead to significant engine performances decrease and degraded emission control. A fault diagnosis system based on structured hypothesis tests is proposed in this paper, in order to detect and isolate different types of failures which are able to affect the pressure control loop in a common rail diesel injection system.