A computational investigation on the influence of the use of elliptical orifices on the inner nozzle flow and cavitation development in diesel injector nozzles

Abstract

Elsevier Molina, S.; Salvador Rubio, FJ.; Carreres Talens, M.; Jaramillo, D. (2014). A computational investigation on the influence of the use of elliptical orifices on the inner nozzle flow and cavitation development in diesel injector nozzles. Energy Conversion and Management. 79:114-127. doi:10.1016/j.enconman.2013.12.015. THE INFLUENCE OF THE USE OF ELLIPTICAL ORIFICES ON THE INNER NOZZLE FLOW AND CAVITATION DEVELOPMENT IN DIESEL INJECTOR A COMPUTATIONAL INVESTIGATION ON

Numerical investigation on effects of nozzle’s geometric parameters on the flow and the cavitation characteristics within injector’s nozzle for a high-pressure common-rail DI diesel engine

“…All the reduction of effective flow area, the generation and the collapse of cavitation bubbles within the orifice will induce the decline of nozzle's flow coefficient, and consequently the failure of injector nozzle [11,12]. Therefore, promoting an in-depth understanding of cavitation characteristics within injector's nozzle and exploring optimal methods to reduce the level of cavitation have become hot topics in the field of internal combustion engines.…”

“…For DI diesel engines, the high-pressure common rail injection system has been widely considered as an utmost promising injection system due to its better effects on spray, better effects on atomization, and smarter control strategy [7][8][9]. For high-pressure common-rail injection system, the phenomenon of cavitation within injector's nozzle is too significant for general performance (especially on the flow characteristics of injectors) that it cannot to be neglected during the design process of high-pressure common-rail injection system [10][11][12].…”

Study of the generated density of cavitation inside diesel nozzle using different fuels and nozzles

“…Battistoni and Grimaldi [14] also made a comparative study on the cavitation inside nozzle and spray characteristics with diesel fuel and biodiesel fuels. Molina et al [15] researched the influence of geometry of orifices on the inner nozzle flow and cavitation development using 5 different nozzles. Salvador et al [16] had researched the influence of the needle lift and backpressure on the internal flow and cavitation by CFD using the RANS method.…”

On the Influence of the Slot Orifice in Diesel Common Rail Nozzle

“…The works reported above analyzed the effects of elliptical orifices on the spray and combustion process, but, as evidenced in [17], the nozzle was treated as a "black box". In the effort to link the internal flow pattern of the nozzle to the shape of the spray (comparing circular and elliptical nozzle holes), Hong et al [18] used transparent acrylic nozzle models, equipped with circular (3 mm diameter) and elliptical orifices having the same geometrical flow area; the authors reported a lower discharge coefficient for the elliptical nozzles and a lower discharge coefficient than that of the circular nozzle at the same Reynolds number.…”

“…The investigations have shown that the hole cross section shape has a tangible effect on the nozzle flow; the influences cover all the factors having a recognized role in the spray formation (cavitation, velocity vector field at orifice exit, turbulence kinetic energy). In [17] the potential of using elliptical nozzle holes has been evaluated, also there comparing the results of four different configurations of elliptical nozzles (two flow areas and two orientations of the ellipse) with a standard circular nozzle hole. In [17] the modeling approach has been based on RANS equations with RNG k-epsilon closure, whereas cavitation modeling has been treated in the frame of a Homogeneous Equilibrium Model, with barotropic equation.…”