An Integrated Experimental-Numerical Study of HSDI Diesel Injection System and Spray Dynamics

This paper presents a complete numerical and experimental characterisation of the transient diesel spray of a modern 5-holes high pressure electronic controlled injector performed in a constant volume pressurised vessel.

The experimental analysis has been carried out using a self-developed injection rate measuring device, a visualisation rig based on a Nd-Yag pulsed laser and a synchronized CCD camera to measure spray penetration and spray cone angles and a PDA equipment to measure droplets size and velocity.

The numerical analysis has been carried out by statically coupling a 1D model of the common rail injection system to a full 3D computation of both gas and fuel spray dynamics. The 1D injection system model has been developed in the AVL HYDSIM environment and the reliability of the model is demonstrated by comparing the numerical results with the experimental data. The multidimensional numerical simulation tool is a modified version of the KIVA-3V code.

The developed numerical tool is calibrated and validated through the comparison between numerical results and measurements in terms of spray penetration, spray cone angle, droplets size and velocity distribution.