ID 118

Micro and macro characterization of an ethanol spray generated by a high pressure-swirl injector inside a chamber

 

Abstract:

The droplet diameters and axial & tangential components of velocities were measured in two radius directions at 50 mm from an automotive DI pressure-swirl/hollow cone injector with injection pressure of 100 bar. Lateral and bottom high speed images helped in the identification of a non-continuous circum-ferential pattern, with formation of cluster of droplets. The PDI results show that there is, in accordance with images, regions of high volume flux of droplets at so-called cluster regions, where at non-cluster regions this volume flux drops considerably. Also, at this distance from injector tip, mean tangential ve-locities below 1m/s are observed. However, inside the spray cone while the injection takes place, the droplet diameters do not change considerably, but when the injection event ends, many small and adjacent droplets are conveyed to the low-pressure region caused by the spray at its center. Longer time filter was applied and revealed that, under the employed experimental setup, there is a considerable error in the calculation of mean velocities and mean droplet diameters as small droplets are recounted due to recircu-lation.