نویسندگان
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
In this paper, the effect of the injector geometry has been investigated on characteristics of the internal nozzle flow and the cavitation phenomenon. To this end, the cavitational flow inside a multi-hole diesel injector was simulated using the computational fluid dynamics. The flow inside the nozzle was considered transient and biphasic (liquid phase and vapor phase) and was simulated using the Eulerian two-fluid model, which is a non-homogeneous model. In this model, governing equations were solved for each phase separately. The interaction between phases was modeled using relevant interfacial exchange terms. To investigate the effect of the nozzle geometry on the cavitational flow, the number of injector holes was varied from 2 to 8. Results showed that by increasing the number of nozzle holes, the structure and the intensity of the vortex flow in the nozzle sac and holes are extremely varied. From the nozzle flow characteristics point of view, an increase in the number of nozzle holes, resulted in a reduction in the injection velocity and the mass flow rate and an increase in the cavitation intensity. Furthermore, the discharge coefficient and the effective area of the nozzle fall with increasing the number of nozzle holes. The simulation method was validated by comparing numerical results with experimental data and a good agreement was achieved.
کلیدواژهها [English]
)