Combustion System Development of a New DX12 Heavy-Duty Diesel Engine with Mechanical Fuel Injection Equipment

Author(s):  
Tae Joong Wang ◽  
Jong Yoon Lee ◽  
Seung Kwon Hwang ◽  
Ja Yun Cho ◽  
Jeong Keun Park ◽  
...  
1994 ◽  
Author(s):  
Yoshihisa Yamaki ◽  
Kazutoshi Mori ◽  
Hiroshi Kamikubo ◽  
Susumu Kohketsu ◽  
Kohji Mori ◽  
...  

Author(s):  
Cosmin E. Dumitrescu ◽  
W. Stuart Neill ◽  
Hongsheng Guo ◽  
Vahid Hosseini ◽  
Wallace L. Chippior

An experimental study was performed to investigate fuel property effects on premixed charge compression ignition (PCCI) combustion in a heavy-duty diesel engine. A matrix of research diesel fuels designed by the Coordinating Research Council, referred to as the Fuels for Advanced Combustion Engines (FACE), was used. The fuel matrix design covers a wide range of cetane numbers (30 to 55), 90% distillation temperatures (270 to 340 °C) and aromatics content (20 to 45%). The fuels were tested in a single-cylinder Caterpillar diesel engine equipped with a common-rail fuel injection system. The engine was operated at 900 rpm, a relative air/fuel ratio of 1.2 and 60% exhaust gas recirculation (EGR) for all fuels. The study was limited to a single fuel injection event starting between −30° and 0 °CA after top dead center (aTDC) with a rail pressure of 150 MPa. The brake mean effective pressure (BMEP) ranged from 2.6 to 3.1 bar depending on the fuel and its injection timing. The experimental results show that cetane number was the most important fuel property affecting PCCI combustion behavior. The low cetane number fuels had better brake specific fuel consumption (BSFC) due to more optimized combustion phasing and shorter combustion duration. They also had a longer ignition delay period available for premixing, which led to near-zero soot emissions. The two fuels with high cetane number and high 90% distillation temperature produced significant soot emissions. The two fuels with high cetane number and high aromatics produced the highest brake specific NOx emissions, although the absolute values were below 0.1 g/kW-h. Brake specific HC and CO emissions were primarily a function of the combustion phasing, but the low cetane number fuels had slightly higher HC and lower CO emissions than the high cetane number fuels.


Author(s):  
Yuanjiang Pei ◽  
Roberto Torelli ◽  
Tom Tzanetakis ◽  
Yu Zhang ◽  
Michael Traver ◽  
...  

Recent experimental studies on a production heavy-duty diesel engine have shown that gasoline compression ignition (GCI) can operate in both conventional mixing-controlled and low-temperature combustion modes with similar efficiency and lower soot emissions compared to diesel at a given engine-out NOx level. This is primarily due to the high volatility and low aromatic content of high reactivity, light-end fuels. In order to fully realize the potential of GCI in heavy-duty applications, accurate characterization of gasoline sprays for high-pressure fuel injection systems is needed to develop quantitative, three-dimensional computational fluid models that support simulation-led design efforts. In this work, the non-reacting fuel spray of a high reactivity gasoline (research octane number of ∼60, cetane number of ∼34) was modeled under typical heavy-duty diesel engine operating conditions, i.e., high temperature and pressure, in a constant-volume combustion chamber. The modeling results were compared to those of a diesel spray at the same conditions in order to understand their different behaviors due to fuel effects. The model was developed using a Lagrangian-Particle, Eulerian-Fluid approach. Predictions were validated against available experimental data generated at Michigan Technological University for a single-hole injector, and showed very good agreement across a wide range of operating conditions, including ambient pressure (3–10 MPa), temperature (800–1200 K), fuel injection pressure (100–250 MPa), and fuel temperature (327–408 K). Compared to a typical diesel spray, the gasoline spray evaporates much faster, exhibiting a much shorter liquid length and wider dispersion angle which promote gas entrainment and enhance air utilization. For gasoline, the liquid length is not sensitive to different ambient temperatures above 800 K, suggesting that the spray may have reached a “saturated” state where the transfer of energy from the hot gas to liquid has already been maximized. It was found that higher injection pressure is more effective at promoting the evaporation process for diesel than it is for gasoline. In addition, higher ambient pressure leads to a more compact spray and fuel temperature variation only has a minimal effect for both fuels.


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