Effect of Ambient Gas Temperature

High-Speed Schlieren Movies of Diesel Sprays
Parameter Low Gas Temperature Moderate Gas Temperature High Gas Temperature
Ambient O2 [%] 21 21 21
Ambient Temperature [K] 800 1000 1200
Ambient Density [kg/m3] 28 28 28
ΔPinj [MPa] 138 138 138
Orifice Diameter [mm] 0.260 0.260 0.260
Download movie

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

The ignition delay (time from start of injection until start of combustion) decreases with increasing ambient temperature. After start of combustion, the spray penetration rate is approximately the same.