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Title: Modeling and control of fuel distribution in a dual-fuel internal combustion engine leveraging late intake valve closings

Journal Article · · International Journal of Engine Research
 [1];  [1];  [2];  [2]
  1. Mechanical, Materials, and Aerospace Engineering Department, Illinois Institute of Technology, Chicago, IL, USA
  2. Fuels, Engine and Aftertreatment Research, Argonne National Laboratory, Argonne, IL, USA

In internal combustion engines, cycle-to-cycle and cylinder-to-cylinder variations of the combustion process have been shown to negatively impact the fuel efficiency of the engine and lead to higher exhaust emissions. The combustion variations are generally tied to differences in the composition and condition of the trapped mass throughout each cycle and across individual cylinders. Thus, advanced engines featuring exhaust gas recirculation, flexible valve actuation systems, advanced fueling strategies, and turbocharging systems are prone to exhibit higher variations in the combustion process. In this study, the cylinder-to-cylinder variations of the combustion process in a dual-fuel internal combustion engine leveraging late intake valve closing are investigated and a model to predict and address one of the root causes for these variations across cylinders is developed. The study is conducted on an inline six-cylinder heavy-duty dual-fuel engine equipped with exhaust gas recirculation, a variable geometry turbocharger, and a fully flexible variable intake valve actuation system. The engine is operated with late intake valve closure timings in a dual-fuel combustion mode in which a high reactivity fuel is directly injected into the cylinders and a low reactivity fuel is port injected into the cylinders. The cylinder-to-cylinder variations observed in the study have been associated with the maldistribution of the port-injected fuel, which is exacerbated at late intake valve timings. The resulting difference in indicated mean effective pressure between the cylinders ranges from 9% at an intake valve closing of 570° after top dead center to 38% at an intake valve closing of 620° after top dead center and indicates an increasingly uneven fuel distribution. The study leverages both experimental and simulation studies to investigate the distribution of the port-injected fuel and its impact on cylinder-to-cylinder variation. The effects of intake valve closing as well as the impact of intake runner length on fuel distribution were quantitatively analyzed, and a model was developed that can be used to accurately predict the fuel distribution of the port-injected fuel at different operating conditions with an average estimation error of 1.5% in cylinder-specific fuel flow. A model-based control strategy is implemented to adjust the fueling at each port and shown to significantly reduce the cylinder-to-cylinder variations in fuel distribution.

Sponsoring Organization:
USDOE
Grant/Contract Number:
EE0003303
OSTI ID:
1437693
Journal Information:
International Journal of Engine Research, Journal Name: International Journal of Engine Research Vol. 18 Journal Issue: 8; ISSN 1468-0874
Publisher:
SAGE PublicationsCopyright Statement
Country of Publication:
United Kingdom
Language:
English

References (21)

Experiments and Modeling of Dual-Fuel HCCI and PCCI Combustion Using In-Cylinder Fuel Blending journal October 2009
In-Cylinder Oxygen Mass Fraction Estimation Method for Minimizing Cylinder-to-Cylinder Variations conference April 2015
The effect of injection timing and intake valve close timing on performance and emissions of diesel PCCI engine with a full engine cycle CFD simulation journal September 2011
Development of Dual-Fuel Low Temperature Combustion Strategy in a Multi-Cylinder Heavy-Duty Compression Ignition Engine Using Conventional and Alternative Fuels journal May 2013
Combustion and exhaust emission characteristics of a dual fuel compression ignition engine operated with pilot Diesel fuel and natural gas journal November 2004
Cylinder-to-Cylinder Variations in Power Production in a Dual Fuel Internal Combustion Engine Leveraging Late Intake Valve Closings journal April 2016
Combustion and Exhaust Emissions in a Direct-injection Diesel Engine Dual-Fueled with Natural Gas conference February 1995
Performance and Emissions of a Heavy-Duty Truck during the UDDS Driving Cycle: Simulation Analysis journal June 2016
Late Intake Valve Closing as an Emissions Control Strategy at Tier 2 Bin 5 Engine-Out NOx Level journal April 2008
Combustion in Gas Fueled Compression: Ignition Engines of the Dual Fuel Type journal July 2003
PCCI Investigation Using Variable Intake Valve Closing in a Heavy Duty Diesel Engine conference April 2007
An Experimental Investigation of Fuel Reactivity Controlled PCCI Combustion in a Heavy-Duty Engine journal April 2010
Heavy-Duty Truck Emissions in the South Coast Air Basin of California journal August 2013
Impact of Cetane Number on Combustion of a Gasoline-Diesel Dual-Fuel Heavy-Duty Multi-Cylinder Engine journal April 2014
Comparison of Life Cycle Greenhouse Gases from Natural Gas Pathways for Medium and Heavy-Duty Vehicles journal May 2015
Study of fuel economy improvement through control of intake valve closing timing: cause of combustion deterioration and improvement journal January 1995
HCCI Operation of a Passenger Car DI Diesel Engine with an Adjustable Valve Train conference April 2006
Impact of Effective Compression Ratio on Gasoline-Diesel Dual-Fuel Combustion in a Heavy-Duty Engine Using Variable Valve Actuation conference September 2015
Dual-Fuel PCI Combustion Controlled by In-Cylinder Stratification of Ignitability conference April 2006
Numerical and Experimental Investigation of Combustion Regimes in a Dual Fuel Engine conference September 2013
Effects of Intake Valve Closing Timing on Gasoline Engine Performance and Emissions conference September 2001