Effect of Nozzle Orifice Diameter

High-Speed Schlieren Movies of Diesel Sprays
ParameterSmall Orifice DiameterLarge Orifice Diameter
Ambient O2 [%]2121
Ambient Temperature [K]10001000
Ambient Density [kg/m3]2828
ΔPinj [MPa]136137
Orifice Diameter [mm]0.2000.260

Download movie

Fuel is #2 diesel fuel. Injector tip to wall is 109 mm.

The penetration rate decreases with decreasing orifice diameter (Naber, 1996).

The momentum of the spray scales with nozzle area for sprays with the same injection pressure above ambient.