A correction method of hole-to-hole variation mass flow of diesel injector equipped on a common-rail DI diesel engine

Abstract

In the present paper, the inner flow characteristic and cavitation phenomena for different injector shapes (characterized by angle α and length–diameter ratio) are analyzed experimentally and numerically. Mathematical models including multi-phases model, volume of fluid model and the k-epsilon turbulence model are validated by experiment. The numerical results show that with the increase of injection angle α, the inception time of cavitation is earlier, the extension velocity of cavitation to nozzle exit is higher and the nozzle fuel mass is less for each cycle. With the increase of length–diameter ratios, the time consumed from the inception to stable state of cavitation is longer and the single nozzle fuel mass increases. Furthermore, a correction method is proposed based on inconsistent length–diameter ratios. It could amend the difference of single nozzle fuel mass and guarantee the uniform fuel mass in axis symmetry direction of engine cylinder.