This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Real-Time Calculation of EGR Rate and Intake Charge Oxygen Concentration for Misfire Detection in Diesel Engines
ISSN: 0148-7191, e-ISSN: 2688-3627
Published September 11, 2011 by SAE International in United States
Annotation ability available
A new procedure for the real-time estimation of the EGR rate and charge oxygen concentration has been developed, assessed and applied to a low-compression ratio GMPT-E EURO V diesel engine.
High EGR rates are usually employed in modern diesel engines to reduce combustion temperatures and NOx emissions, especially at medium-low load and speed conditions. The EGR rate is usually calibrated in steady-state conditions, but, under transient conditions, it can be responsible for misfire occurrence or non optimal combustion cycles, if not properly controlled. In other words, combustion instabilities can occur, especially during tip-in maneuvers, which imply transition from high EGR (low load) to low EGR (high load) rates. Misfire is determined by a temporary reduction in the intake charge oxygen concentration during the closure of the EGR valve.
Therefore, a model-based approach for real-time estimation of the EGR rate and intake charge oxygen concentration is a powerful tool that could allow the engine ECU to prevent misfire occurrence.
In this paper, a semi-empirical correlation has been developed to estimate the EGR rate under steady-state and transient operating conditions, on the basis of the measured pressure in the intake manifold, of the measured pressure and temperature upstream from the EGR valve, and of the duty cycle signal of the EGR valve. The intake charge oxygen concentration has been estimated on the basis of the measurements of the air mass-flow rate and injected fuel mass.
The proposed technique has been applied to a modern EURO V diesel engine, in order to analyze two different engine transients: a severe tip-in maneuver with misfire occurrence and an acceleration ramp during the ECE cycle. The methodology has proved to be effective in the real-time monitoring of the EGR rate and intake charge oxygen concentration and to be simple enough to be implemented in the engine ECU in order to diagnose misfire occurrence in advance.
CitationCatania, A., Finesso, R., and Spessa, E., "Real-Time Calculation of EGR Rate and Intake Charge Oxygen Concentration for Misfire Detection in Diesel Engines," SAE Technical Paper 2011-24-0149, 2011, https://doi.org/10.4271/2011-24-0149.
- Nakayama, S. Fukuma, T. Matsunaga, A. Miyake, T. Wakimoto, T. “A New Dynamic Combustion Control Method Based on Charge Oxygen Concentration for Diesel Engines” SAE Technical Paper 2003-01-3181 2003 10.4271/2003-01-3181
- Nakayama, S. Ibuki, T. Hosaki, H. Tominaga, H. “An Application of Model Based Combustion Control to Transient Cycle-by-Cycle Diesel Combustion,” SAE Technical Paper 2008-01-1311 2008 10.4271/2008-01-1311
- Catania, A. E. Finesso, R. Spessa, E. Catanese, A. Landsmann, G. “Combustion Prediction by a Low-Throughput Model in Modern Diesel Engines,” SAE Technical Paper 2011-01-1410 2011 10.4271/2011-01-1410
- Catania, A.E. Finesso, R. Spessa, E. “Predictive Zero-Dimensional Combustion Model for DI Diesel Engine Feed-Forward Control” ‘Energy Conversion and Management’ 52 10 September 2011 3159 3175 2011 Elsevier 0196-8904 http://dx.doi.org/10.1016/j.enconman 2011 05 003
- d'Ambrosio, S. Finesso, R. Spessa, E. “Calculation Of Mass Emissions, Oxygen Mass Fraction And Thermal Capacity Of The Inducted Charge In SI And Diesel Engines From Exhaust And Intake Gas Analysis” Fuel Elsevier 90 152 166 0016-2361 10.1016/j.fuel.2010.08.025 2011
- Klein, P. Gruter, R. Loffeld, O. “Real-Time Estimation of the Exhaust Gas Recirculation Ratio Based on Cylinder Pressure Signals,” SAE Technical Paper 2007-01-0493 2007 10.4271/2007-01-0493
- Azzoni, P. M. Minelli, G. Moro, D. Serra, G. “A Model for EGR Mass Flow Rate Estimation,” SAE Technical Paper 970030 1997 10.4271/970030
- Friedrich, I. Liu, C. S. Oehlerking, D. “Coordinated EGR-Rate Model-Based Controls of Turbocharged Diesel Engines via an Intake Throttle and an EGR Valve” Vehicle Power and Propulsion Conference 2009
- Catania, A. E. d'Ambrosio, S. Ferrari, A. Finesso, R. Spessa, E. Avolio, G. Rampino, V. “Experimental Analysis of Combustion Processes and Emissions in a 2.0L Multi-Cylinder Diesel Engine Featuring a New Generation Piezo-Driven Injector,” SAE Technical Paper 2009-24-0040 2009 10.4271/2009-24-0040
- Catania, A. E. d'Ambrosio, S. Finesso, R. Spessa, E. Cipolla, G. Vassallo, A. “Combustion System Optimization of a Low Compression-Ratio PCCI Diesel Engine for Light-Duty Application,” SAE Int. J. Engines 2 1 1314 1326 2009 10.4271/2009-01-1464
- Cipolla, G. Vassallo, A. Catania, A. E. Spessa, E. Stan, C. Drischmann, L. “Combined Application of CFD Modeling and Pressure-based Combustion Diagnostics for the Development of a Low Compression Ratio High-performance Diesel Engine,” SAE Technical Paper 2007-24-0034 2007 10.4271/2007-24-0034
- Catania, A.E. Ferrari, A. Spessa, E. “Numerical-Experimental Study and Solutions to Reduce the Dwell Time Threshold for Fusion-Free Consecutive Injections in a Multijet Solenoid-Type C.R. System” Journal of Engineering for Gas Turbines and Power 131 022804-1 022804-14 0742-4795 10.1115/1.2938394