Targeting the issue of inconsistent fuel injection across multiple holes in high-pressure common rail injectors, this study integrates the spray momentum method with spray visualization techniques to conduct an in-depth experimental investigation into the liquid fuel injection and spray characteristics of each injector hole under varying injection pressures and pulse widths. The research findings indicate that under conditions of low injection pressure and narrow injection pulse width, the average volatility rate of cycle fuel injection quantity
, the difference coefficient of cycle fuel injection quantity
, the difference coefficient of spray penetration
and the difference coefficient of spray equivalence ratio
of each injector hole are larger, and the inconsistency of the liquid fuel injection/spray is larger. With the increase in injection pressure or pulse width, fuel injection inconsistency decreases. However, at higher levels of injection pressure or pulse width, further increases have minimal impact on the fuel injection inconsistency across individual injection holes. The primary influence of injection pressure and pulse width on fuel injection inconsistency is through their effect on the movement of the needle valve. Under the conditions of injection pressure or injection pulse width where the needle valve cannot reach the maximum lift, the instability of the needle valve movement causes frequent changes in the flow area between the needle valve and the needle valve seat, resulting in greater injection inconsistency. Under the conditions of the injection pressure or injection pulse width that enables the needle valve to reach the maximum lift, the fuel injection inconsistency is determined by the structural parameters of the injection hole, and the fuel injection inconsistency is small in this state. By selecting an appropriate combination of injection pressure and pulse width, the fuel injection inconsistency of the injector can be minimized.
