Experimental Analysis on Fuel Flow Characteristics in the Nozzle for Direct Injection Engines 931002
The purpose of this study is to make clear the relationship between flow characteristics in the nozzle and injected spray characteristics. In this paper, we discuss the effect of the sac volume in the standard hole type nozzle on fuel flow and spray. The main object of this paper is to analyze fuel flow characteristics in the nozzle by using the enlarged model nozzles.
Spray investigations confirmed that reducing the sac volume causes changes in the fuel injection direction at the initial stage of injection and in the spray penetration over consecutive injection.
Flow investigations in the injection hole clarified that meandering the flow in the hole causes changes in the fuel injection direction. Flow investigations in the sac chamber clarified that separating the flow from the sac wall causes meandering the flow in the hole.
Furthermore, the methods to restrain the flow in the sac chamber from separating from the sac wall were discussed.
Citation: Date, K., Nobechi, H., Kano, H., Kato, M. et al., "Experimental Analysis on Fuel Flow Characteristics in the Nozzle for Direct Injection Engines," SAE Technical Paper 931002, 1993, https://doi.org/10.4271/931002. Download Citation