Assessment of Engine Control Parameters Effect to Minimize GHG Emissions in a Dual Fuel NG/Diesel Light Duty Engine

Dual fuel engines induce benefits in terms of pollutant emissions of PM and NOx together with carbon dioxide reduction and being powered by natural gas (mainly methane) characterized by a low C/H ratio. Therefore, using natural gas (NG) in diesel engines can be a viable solution to reevaluate this type of engine and to prevent its disappearance from the automotive market, as it is a well-established technology in both energy and transportation fields. It is characterized by high performance and reliability. Nevertheless, further improvements are needed in terms of the optimization of combustion development, a more efficient oxidation, and a more efficient exploitation of gaseous fuel energy. To this aim, in this work, a CFD numerical methodology is described to simulate the processes that characterize combustion in a light-duty diesel engine in dual fuel mode by analyzing the effects of the changes in engine speed on the interaction between fluid-dynamics and chemistry as well as when the diesel/natural gas ratio changes at constant injected diesel amount. With the aid of experimental data obtained at the engine test bench on an optically accessible research engine, models of a 3D code, i.e., KIVA-3V, were validated. The ability to view images of OH distribution inside the cylinder allowed us to better model the complex combustion phenomenon of two fuels with very different burning characteristics. The numerical results also defined the importance of this free radical that characterizes the areas with the greatest combustion activity.

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Experimental Investigation of Effects of Split Diesel-Pilot Injection on Emissions From Ammonia-Diesel Dual Fuel Engine

10.1115/icef2021-66341 ◽

2021 ◽

Author(s):

Yoichi Niki

Keyword(s):

Diesel Fuel ◽

Internal Combustion Engines ◽

Ghg Emissions ◽

High Reactivity ◽

Dual Fuel ◽

N2o Emissions ◽

Injection Timing ◽

Pilot Injection ◽

Reduce Emissions ◽

And Performance

Abstract NH3 has been investigated for its use as an alternative fuel including for use in internal combustion engines. In NH3 combustion, emissions of unburned NH3 with toxicity and N2O as a combustion product with high global warming potential (GWP) are important issues. However, few researchers have investigated NH3 and N2O emissions from NH3 assisted diesel engines operated using NH3–diesel dual fuel. We investigate a combustion strategy to reduce these emissions with a single-cylinder diesel engine mixed NH3 gas into the intake air. We found that an early diesel pilot injection reduced unburned NH3 and N2O emissions while HC and CO emissions increased. It was also reported that NH3 and diesel fuel work as low and high reactivity fuel for reactivity controlled compression ignition combustion (RCCI), respectively. Our previous study reports the aspects of RCCI on NH3–diesel dual fuel engine to some extent. The injection timing of diesel fuel and the quantity of NH3 govern the emissions and performance on RCCI combustion. These effects need to be investigated to manipulate the RCCI combustion and reduce emissions. This paper reports the efficiency and emissions for the diesel pilot injection timing sweep at various NH3 supply quantities and the effects of a split injection on the emissions and a combustion phase. In addition, we estimated the reduction in GHG emissions using a NH3–diesel dual fuel engine, which applied the early diesel pilot injection, compared with the diesel only operation, considering the N2O GWP.

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Smart rule-based diesel engine control strategies by means of predictive driving information

International Journal of Engine Research ◽

10.1177/1468087419835696 ◽

2019 ◽

Vol 20 (10) ◽

pp. 1047-1058 ◽

Cited By ~ 5

Author(s):

Giovanni Vagnoni ◽

Markus Eisenbarth ◽

Jakob Andert ◽

Giuseppe Sammito ◽

Joschka Schaub ◽

...

Keyword(s):

Fuel Consumption ◽

Control Strategies ◽

Control Unit ◽

Future Research ◽

Engine Control ◽

Test Cycle ◽

Rule Based ◽

Prediction Horizon ◽

Light Duty ◽

Path Control

The increasing connectivity of future vehicles allows the prediction of the powertrain operational profiles. This technology will improve the transient control of the engine and its exhaust gas aftertreatment systems. This article describes the development of a rule-based algorithm for the air path control, which uses the knowledge of upcoming driving events to reduce especially [Formula: see text] and particulate (soot) emissions. In the first section of this article, the boosting and the lean [Formula: see text] trap systems of a diesel powertrain are investigated as relevant sub-systems for shorter prediction horizons, suitable for Car-to-X communication range. Reference control strategies, based on state-of-the-art engine control unit algorithms and suitable predictive control logics, are compared for the two sub-systems in a model in the loop simulation environment. The simulation driving cycles are based on Worldwide harmonized Light-duty Test Cycle and Real Driving Emissions regulations. Due to the shorter, and consequently more probable, prediction horizon and the demonstrated emission improvements, a dedicated rule-based algorithm for the air path control is developed and benchmarked in the Worldwide harmonized Light-duty Test Cycle as described in the second part of this article. Worldwide harmonized Light-duty Test Cycle test results show an improvement potential for engine-out soot and [Formula: see text] emissions of up to 5.2% and 1.2%, respectively, for the air path case and a reduction of the average fuel consumption in Real Driving Emissions of up to 1% for the lean NOx trap case. In addition, the developed rule-based algorithm allows the adjustment of the desired NOx–soot trade-off, while keeping the fuel consumption constant. The study concludes with brief recommendations for future research directions, as for example, the introduction of a prediction module for the estimation of the vehicle operational profile in the prediction horizon.

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Microprocessor Dual-Fuel Diesel Engine Control System

10.4271/861577 ◽

1986 ◽

Cited By ~ 2

Author(s):

L. E. Gettel ◽

G. C. Perry ◽

J. Boisvert ◽

P. J. O'Sullivan

Keyword(s):

Control System ◽

Diesel Engine ◽

Dual Fuel ◽

Engine Control ◽

Engine Control System

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Meeting the Challenge: A Stochastic Assessment of the U.S. Light-Duty Vehicle Fuel Economy Standards

ASME 2012 6th International Conference on Energy Sustainability, Parts A and B ◽

10.1115/es2012-91172 ◽

2012 ◽

Cited By ~ 1

Author(s):

Parisa Bastani ◽

John B. Heywood ◽

Chris Hope

Keyword(s):

Fuel Economy ◽

Ghg Emissions ◽

Corporate Average Fuel Economy ◽

Passenger Cars ◽

Policy Model ◽

Light Duty ◽

Stochastic Transport ◽

Light Trucks ◽

Light Duty Vehicle ◽

The U.S

The U.S. Department of Transport and EPA have recently proposed further regulation of the light-duty vehicle corporate average fuel economy and GHG emissions for model years 2017 to 2025. Policy makers are setting more stringent targets out to 2025 in a context of significant uncertainty. These uncertainties need to be quantified and taken into account systematically when evaluating policies. In this paper, a stochastic technology and market vehicle fleet analysis is carried out, using the STEP (Stochastic Transport Emissions Policy model), to assess the probability of meeting the proposed CAFE targets in 2016 and 2025, and identify factors that play key roles in the near and midterm. Our results indicate that meeting the proposed targets requires (a) aggressive technological progress rate and deployment, (b)aggressive market penetration of advanced engines and powertrains, (c) aggressive vehicle downsizing and weight reduction, and (d) a high emphasis on reducing fuel consumption. Three scenarios are examined to assess the likelihood of meeting the proposed targets. The targets examined here, 32.5 and 34.1 mpg in 2016 and 44 and 54.5 mpg in 2025, are reduced from the nominal CAFE values after allowing for the various credits in the proposed rulemaking. The results show that there is about a 42.5% likelihood of the passenger cars average fuel economy falling below 32.5 mpg and a 5.3% likelihood of it exceeding 34.1 mpg in 2016, and about a 4% chance of it exceeding 44 mpg in 2025, under the plausible-ambitious scenario. Under the EPA/DOT preferred alternative scenario, the likelihood of passenger cars average fuel economy meeting or exceeding 34.1 mpg in 2016 and 44 mpg in 2025 increases to about 74% and 34.5% respectively. The probability of meeting these combined CAFE targets drops to less than 1% in both near and mid terms, once light trucks are included in the mix. This analysis quantifies the probability of meeting the targets therefore to enable risk-based contingency planning, and identifies key drivers of uncertainty where further strategic research is needed.

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