Effects of Cetane Number, Aromatics, and Oxygenates on Emissions From a 1994 Heavy-Duty Diesel Engine With Exhaust Catalyst

1995 ◽  
Author(s):  
Kent B. Spreen ◽  
Terry L. Ullman ◽  
Robert L. Mason
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.


2019 ◽  
Vol 2 (1) ◽  

Ignition improver additives are used to improve the ignition quality, or reduce the ignition delay; i.e. the time between when fuel is injected and time when combustion start is different this difference in time is minimize by additive is called cetane improver (CN). The Cetane Number (CN) is the most widely accepted measure of ignition quality to get desired value of centane number some additive are used hence ignition improvers are usually characterized by the fact that at what extent they can increase CN. By increasing cetane number we have two benefits that it helps smoother combustion and lower emissions. Fuel properties are always considered as one of the main factors to diesel engines concerning performance of cetane improver. There are still challenges for researchers to identify the most correlating and non-correlating fuel properties and their effects on cetane improver .In this study to derive the most un-correlating and correlating properties. In parallel, sensitivity analysis was performed for the fuel properties as well as to effect on performance of cetane improver


Author(s):  
W. Stuart Neill ◽  
Wallace L. Chippior ◽  
Ken Mitchell ◽  
Craig Faibridge ◽  
Rene´ Pigeon ◽  
...  

The exhaust emissions form a single-cylinder version of a heavy-duty diesel engine with exhaust gas recirculation (EGR) were measured with eight high-cetane components blended into an ultra-low sulphur diesel base fuel. the blending components evaluated were conventional nitrate and peroxide cetane improver additives, paraffins from two sources, three ethers, and soy methyl ester. The blending components were used to increase the cetane number of a base fuel by ten numbers, from 44 to 54. Exhaust emissions were measured using the AVL eight-mode steady-state test procedure. PM and NOx emissions from the engine were fairly insensitive to ignition quality improvement by nitrate and peroxide cetane improvers. Soy methyl ester and two of the ethers, 1,4 diethoxybutane and 2-ethoxyethyl ether, significantly reduced PM emissions, but increased ONx emissions. The two paraffinic blending components reduced both PM and NOx emissions.


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 with a rail pressure of 150 MPa. The brake mean effective pressure (BMEP) ranged from 3.2 to 3.6 bar depending on the fuel and fuel 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 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 when the start of combustion occurred before the end of fuel injection. 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-hr. 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.


2021 ◽  
Vol 156 ◽  
pp. 105781
Author(s):  
Louise Gren ◽  
Vilhelm B. Malmborg ◽  
John Falk ◽  
Lassi Markula ◽  
Maja Novakovic ◽  
...  

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