NUMERICAL CHARACTERIZATION OF AN ETHANOL SPRAY PRODUCED BY A PRESSURE-SWIRL INJECTOR USING DIFFERENT INJECTION PRESSURES

Resumo

This study aims to compare the numerical model of a spray generated by a pressure-swirl injector for multiple injection pressures with the experimental tests performed using this injector. To provide data to the numerical spray model, experimental tests were performed at Center of Mobility Technology (CTM-UFMG) and data of liquid penetrations and spray geometry were obtained. The injection pressures in which the tests operated were 30, 50, 70, 90, 100, and 110 bar, with the injection taking place in a chamber at atmospheric pressure. Then, all these conditions, as well as mass flow rate and injection duration, were reproduced numerically in order to represent adequately the phenomenon observed experimentally. To calculate the experimental data, images were achieved by high speed recording combined with shadowgraph technique and Matlab treatment. Then, similarly to the experimental methodology, the numerical results were also treated using Matlab to compare the spray characteristics of interest in this study. The numerical and experimental results showed a good agreement and it was observed that the spray penetration is larger and the droplet sizes are smaller when the injection pressure is higher.