THE EFFECT OF FLASH BOILING ON BREAK UP AND ATOMIZATION IN GDI SPRAYS

Abstract

In this work the effect of flash boiling on liquid breakup and atomization is first reviewed and then described in detail for two multistream gasoline direct injectors operating with RON-95 gasoline at 120 bar and 200 bar pressure with a fuel injection duration of 0.8 ms into sub-atmospheric pressures between 1 and 0.1bar and temperatures between 20°C and 100°C. The sprays were injected into the optically accessed chamber whose temperature and pressure were independently controlled. Mie imaging with a single shot CCD camera was applied to obtain images of the sprays under a matrix of the above conditions. In order to investigate the influence of the cone angle on the stream to stream interaction, two different injectors were used, one with a 60 degree and the other with a 90 degree nominal external cone angle. Paper ID ILASS08-6-1