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A Second Law Analysis of High Efficiency Low Emission Gasoline Engine Concepts
Technical Paper
2006-01-0491
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
A second law analysis of spark ignition (SI) engines has been conducted to identify areas in which work capability is presently lost due to either thermodynamic irreversibilities or undesirable work transfers. The impact of advanced combustion strategies on raising powertrain efficiency is assessed. The modeling study relies on two simulation codes: a one-dimensional gas-dynamic simulation code for air flow and heat transfer external to the cylinder, and a single-cylinder thermodynamic cycle simulation code modified to incorporate a second law (Availability) analysis. Modeling results are presented for a base case 3.0 liter, port fuel injection (PFI) gasoline engine with a 10.5 compression ratio (CR), operated homogeneously with a stoichiometric fuel/air ratio. The effects on engine efficiency of lean burn operation, increased CR, and homogeneous charge compression ignition (HCCI) are assessed via two additional cases: a) a lean burn (λmax=1.7), direct injection, 12 CR, 2.9 liter engine; and b) an ultra-lean burn (λmax=5.0) direct injection, 16 CR, 2.7 liter engine. These strategies show the potential to raise the peak engine thermal efficiency from ∼35% to 43%. The Availability analyses show that while lean burn operation leads to higher engine efficiency due to reduced exhaust and in-cylinder heat losses, combustion irreversibilities are increased (as a fraction of available fuel energy), reflecting the lower temperature at which heat release occurs. The combustion losses are greatest for the ultra-lean burn case, as it operates at the highest λ values. The effects on work capability losses of HCCI vs. SI operation are estimated by considering the differences in burn rate, heat transfer, and combustion phasing. The analyses indicate that HCCI offers modest efficiency improvements vs. an optimized lean burn SI engine, though important indirect benefits exist through reduced Nox production. Fuel implications for reducing second law losses are discussed, and concepts for reducing the remaining losses are proposed.
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Farrell, J., Stevens, J., and Weissman, W., "A Second Law Analysis of High Efficiency Low Emission Gasoline Engine Concepts," SAE Technical Paper 2006-01-0491, 2006, https://doi.org/10.4271/2006-01-0491.Also In
References
- Primus R.J. Flynn P.F. “Diagnosing the real performance impact of diesel engine design parameter variation (a primer in the use of second law analysis,” Proceedings of International Symposium on Diagnostics and Modeling of Combustion in Reciprocating Engines (COMMODIA) 529 538 1985
- Primus R.J. “A second law approach to exhaust system optimization,” SAE paper 840033 1984
- Caton J.A. “A review of investigations using the second law of thermodynamics to study internal combustion engines,” SAE Paper 2001-01-1081
- Caton J.A. “Operating characteristics of a spark-ignition engine using the second law of thermodynamics: effects of speed and load,” SAE paper 2000-01-0952
- Heywood J.B. Internal Combustion Engine Fundamentals McGraw-Hill, Inc. New York, NY 1988
- Rakopoulos C.D. Kyritsis D.C. “Comparative second-law analysis of internal combustion engine operation for methane, methanol, and dodecane fuels” Energy 26 705 22 2001
- Rakopoulos C.D. Giakoumis E.G. “Parametric study of transient turbocharged diesel engine operation from the second-law perspective,” SAE Paper 2004-01-1679
- Keenan J.H. Brit. J. of Appl. Phys. 2 183 1951
- Dunbar W.R. Lior N. “Sources of combustion irreversibility,” Combust. Sci. and Tech. 103 41 61 1994
- Vogler T.C. Weissman W. “Thermodynamic Availability analysis for maximizing a system's efficiency” Chem. Eng. Prog. 35 42 1988
- GT-Power User's Manual, Version 6.1, Gamma Technologies Westmont, IL 2004
- Heywood J.B. Higgins J.M. Watts P.A. “Development and use of a cycle simulation to predict SI engine efficiency and NOx emissions,” SAE Paper 790291
- Mansouri S.H. Heywood J.B. Radhakrishnan K. “Divided-chamber diesel engines, part 1: a cycle-simulation which predicts performance and emissions,” SAE Paper 820273
- Poulos S.G. Heywood J.B. “The effect of chamber geometry on spark-ignition engine combustion,” SAE Paper 830334
- Patton K.J. Nitschke R.G. Heywood J.B. “Development and evaluation of a friction model for spark-ignited engines,” SAE Paper 890836
- Sandoval Heywood J.B. “An improved friction model for spark-ignition engines,” SAE Paper 2003-01-0725
- Reilly D.J. Andersen R.P. Casparian R.J. Dugdale P.H. “Saturn DOHC and SOHC Four Cylinder Engines” SAE Paper 910676
- Noguchi T. Kuramoto A. Kono T. Kawakita T. “New light-weight 3-liter V6 Toyota engine with high-output torque, good fuel economy and low-exhaust emission levels,” SAE Paper 950805
- Kee R.J Rupley F.M. Miller J.A. “Chemkin-II: a Fortran chemical kinetics package for the analysis of gas-phase chemical kinetics,” SAND89-8009 Sandia National Laboratories Albuquerque, NM 1989
- Alkidas A.C. El Tahry S.H. “Contributors to the fuel economy advantage of DISI engines over PFI engines,” SAE Paper 2003-01-3101
- Filipi Z.S. Chang J. Guralp O.A. Assanis D.N. Kuo T.-W. Najt P.M. Rask R.B. “New heat transfer correlation for an HCCI engine derived from measurements of instantaneous surface heat flux,” SAE Paper 2004-01-2996
- Zhu G.G. Daniels C.F. Winkelman J. “MBT timing detection and its closed-loop control using in-cylinder pressure signal,” SAE Paper 2003-01-3266
- Caton J.A. “On the destruction of Availability (exergy) due to combustion processes - with specific applications to internal-combustion engines,” Energy 25 1097 117 2000
- Lutz A.E. Rupley F.M. Kee R.J. “EQUIL: a Chemkin implementation of Stanjan, for computing chemical equilibria,” Technical Report Sandia National Laboratories Livermore, CA 1996
- Dec J.E. Sjöberg M. “A Parametric Study of HCCI Combustion--The Sources of Emissions At Low Loads and the Effects of GDI Fuel Injection,” SAE Paper 2003-01-0752
- VanDerWege B.A. Han Z. Iyer C.O. Muñoz R.H. Yi J. “Development and analysis of a spray-guided DISI combustion system concept,” SAE Paper 2003-01-3105
- Richman R.H. Stringer J. “Prospects for efficient thermoelectrics in the near term,” Proceedings of the DARPA/ONR/DOE High Efficiency Thermoelectrics Workshop March 2002 San Diego, CA
- Caton J.A. “Use of a cycle simulation incorporating the second law of thermodynamics: Results for spark-ignition engines using oxygen enriched combustion air,” SAE Paper 2005-01-1130
- Daw S. Chakravarthy K. Conklin J. Graves R. “The potential for reducing combustion irreversibility with preheat” Int. J. Hydrogen Energy
- Lutz A.E. Larson R.S. Keller J.O. “Thermodynamic comparison of fuel cells to the Carnot cycle,” Int. J. Hydrogen Energy 27 1103 11 2002