In previous work, high injection pressures and multiple injections per engine stroke were shown to be effective at reducing the NOx and particulate emissions of DI Diesel engine combustion. A series of experiments were performed to study the effects of injection pressure, back pressure, and injection strategy on the spray characteristics for multiple injections. An injection system which was capable of multiple injections was used to introduce diesel fuel into a constant volume cold spray chamber. Parallel engine experiments were conducted using the same injectors as in this work. In these engine tests, emissions (NOx and particulate) were measured. The engine experiments were used to develop the injector and chamber operating conditions for this work. The injection pressure was varied up to 90 MPa. The back pressure in the spray chamber was set with compressed argon gas, to make the density of the gas equal to the cylinder density at the start of injection of the combustion emission tests. Double and triple injections along with different dwells under the same injection pressure (90 MPa), ambient density (27 kg/m{sup 3}) and similar fuel delivery (168 mg/inj) were analyzed to reveal the effect of multiple injections on spray tip penetration length, spraymore » cone angle, and droplet size.« less
[1]
I. Yamaguchi,et al.
Observation of High Pressure Fuel Spray with Laser Light Sheet Method
,
1992
.
[2]
Rolf D. Reitz,et al.
Reducing Particulate and NOx Emissions by Using Multiple Injections in a Heavy Duty D.I. Diesel Engine
,
1994
.
[3]
C. M. Sliepcevich,et al.
Scattering of Light by Large Spherical Particles
,
1953
.
[4]
Rolf D. Reitz,et al.
Reducing Particulate and NOx Using Multiple Injections and EGR in a D.I. Diesel
,
1995
.
[5]
Yoshihisa Yamamoto,et al.
Development of new electronically controlled fuel injection system ECD-U2 for diesel engines
,
1991
.
[6]
Rolf D. Reitz,et al.
Measurement of the Effect of Injection Rate and Split Injections on Diesel Engine Soot and NOx Emissions
,
1994
.
[7]
Shigeru Shundoh,et al.
NOx Reduction from Diesel Combustion Using Pilot Injection with High Pressure Fuel Injection
,
1992
.
[8]
T. Kamimoto,et al.
A New Technique for the Measurement of Sauter Mean Diameter of Droplets in Unsteady Dense Sprays
,
1989
.