This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Predictive Simulation Strategies for the 2-Stroke Scavenging Process within the Scope of the Development Process
Technical Paper
2005-32-0099
Annotation ability available
Sector:
Language:
English
Abstract
The wide variety of applications of the loop scavenged 2-stroke engine is based on 3 advantages which emerge from the 2-stroke working principle: the high power density, the low weight, and the low production costs. An important aim of research activities in the field of 2-stroke engines is to optimize these advantages while minimizing the known disadvantages of high emissions and fuel consumption. Important tasks of the research work within the development process are the prediction of power and emissions of engine concepts and the simulation with special regard to the scavenging process and the high pressure cycle.
In this area of research two state of the art simulation approaches exist. The first one is a detailed simulation of the scavenging and combustion process which is necessary to understand and optimize the fundamentals of the 2-stroke engine. The second one is a predictive simulation which is required to determine basic engine parameters in order to shorten the development time. The detailed simulation is usually done with the use of 3D-CFD-simulation codes which are able to model complex geometries and to simulate e.g. the combustion process and fuel spray. Unfortunately the 3D-simulation is rather dedicated to evaluation and analysis, as measurement data for initial conditions are required and the model-build up and calculation times are relatively high. This leads to the fact that most times the simulation status does not correspond with the development progress and / or the simulation results are not achieved before the prototype phase begins. Regarding gas dynamics, the 1D-simulation seems to be more applicable for predictive simulation as the model is simpler and therefore requires less computational time compared to the 3D-approach. This means that a high number of iterations can be calculated in order to get a converged solution which lowers the demands on initial conditions. Detailed understanding of the thermodynamic processes and correct prediction and optimization of power carried out within the time frame of the development process is the only possibility to achieve future emission levels while maintaining high power. For these rising demands on predictive and detailed simulation strategies a combination of the two approaches is necessary.
In the present paper, the existing 0D-, 1D- and 3D- simulation techniques and the current approaches of a combination or coupling of the 0D-, 1D- and 3D- simulation will be described in detail including a discussion of their advantages and disadvantages. A comparison of their integration possibilities into the developmental process is also performed and special focus will be put on the determination of the proper simulation approach for the single domains of the simulation model (the cylinder itself, for example, requires a different simulation approach than the exhaust or intake part). The paper will describe experiences with these simulation strategies within the development process and presents examples of performed simulation tasks. Finally, a new strategy for an integrated and optimized 1D- and 3D-simulation will be presented. This new approach will enable an effective and accurate simulation of the 2-stroke scavenging within the development process, its impact on development time and prediction quality will be considered in future publications.
Recommended Content
Authors
- Rainer J. ROTHBAUER - Christian Doppler Laboratory “Thermodynamics of Reciprocating Engines”, Graz University of Technology
- Roland H. MARGELIK - Christian Doppler Laboratory “Thermodynamics of Reciprocating Engines”, Graz University of Technology
- Muhammad M. ASLAM - Christian Doppler Laboratory “Thermodynamics of Reciprocating Engines”, Graz University of Technology
- Raimund A. ALMBAUER - Christian Doppler Laboratory “Thermodynamics of Reciprocating Engines”, Graz University of Technology
- Stephan P. SCHMIDT
- Karl GLINSNER
Citation
ROTHBAUER, R., MARGELIK, R., ASLAM, M., ALMBAUER, R. et al., "Predictive Simulation Strategies for the 2-Stroke Scavenging Process within the Scope of the Development Process," SAE Technical Paper 2005-32-0099, 2005.Also In
References
- Pischinger R. Klell M. Sams T. Springer Verlag Wien 2002
- Sun J. H. Yates D. A. Winterbone D. E. “Evaluation of the Intensity of Turbulent Velocities by Using a Cross-Correlation Technique for Pattern Tracking” SAE Paper 960267 1996
- Reid Michael G. Douglas Roy “Quasi-Dimensional Modelling of Combustion in a Two-Stroke Cycle Spark Ignition Engine” SAE Paper 941680 1994
- Dai Wen Newman Charles E. Davis George C. “Predictions of In-Cylinder Tumble Flow and Combustion in SI Engines with a Quasi-Dimensional Model” SAE Paper 961962
- Reid M. Douglas R. “A Closed Cycle Simulation Model with Particular Reference to Two-Stroke Cycle Engines” SAE 911847 1991
- Arais J. Moreno E. Navarro E. Varela E. “Using 1-D and 3-D Models for the Simulation of Gas Exchange Processes” SAE 2000-01-0658 2001
- Yangbing Z Strauss S Lucier P. Craft T. “Predicting and Optimizing Two-Stroke Engine Performance Using Multidimensional CFD” SETC 2004-0032-0039 2004
- Prenninger, P. Bartsch, P. “Application of AVL-BOOST-FIREHybrid Calculation in Engine Optimization” Proceedings of 3rd International FIRE User Meeting AVL LIST GmbH 1997
- Maynes B. D. J. Kee R. J. Kenny R. G. Fleck R. Mackey D. O. Foley L. “Prediction of Formula 1 Engine and Airbox Performance using Coupled Virtual 4-Stroke and CFD Simulations” SAE Paper 2002-01-3318 2002
- Chiavola O “Integrated modelling of internal combustion engine intake and exhaust systems” Proc Instn Mech Engrs 215 2001
- Chiatti G. Chiavola O. “Multicode Prediction of the Influence of the Exhaust System on the Performance of a Turbocharged Engine” Journal of Engineering for Gas Turbines and Power 124 695 2002
- Blair, G. P. Hinds, E. T. Fleck, R. “Predicting the performance characteristics of two-cycle engines fitted with reed induction valves” SAE paper 790842 1979
- Cunningham G Kee R J Kenny R G “Reed valve modelling in a computational fluid dynamics simulation of the two-stroke engine” Proc Instn Mech Engrs 213 1999
- Fleck, R. Blair, G. P. Houston, R. A. R. “An improved model for predicting reed valve behavior in two-stroke cycle engines” SAE paper 871654 1987
- Mitianiec Wladyslaw Bogusz Andrzej “Theoretical and Experimental Study of Gas Flow Through Reed Valve in a Two-Stroke Engine” SAE Paper 961802 1996
- Cunningham G Kee R J Boyall J “CFD prediction of crankcase flow regimes in a crankcase scavenged two stroke engine” SAE paper 970361 1997
- Jante A. 1960 Akademie-Verlag Berlin
- Benson R.S. Brandham P.J. 1969 “A Method for Obtaining a Quantitative Assessment of the Influence of Charge Efficiency on Two-Stroke Engine Performance”
- Benson R.S. Whitehouse N.D. 1979 Internal Combustion Engines 1 2 Pergamon, Oxford
- Blair G.P. Design and Simulation of Two-Stroke Engines The Queen's University of Belfast SAE 793 Warrendale Pa. 1-56091-685-0 1992
- Blair G.P. The basic Design of Two-Stroke Engines The Queen's University of Belfast SAE 793 Warrendale Pa. 1-56091-008-9 1990
- Laimböck F.J. Graz University of Technology 1985
- Han, Z. Fan, L. Reitz, R.D. “Multidimensional modelling of Spray atomization and air-fuel mixing in a direct-injection spark-ignition engine” SAE Paper 979884 1997
- De Vita A. Allocca L. “Experimental Analysis and CFD Simulation of GDI Sprays” SAE Paper 2003-01-0004 2003
- Fan L. Han L. Z. Reitz R. D. “Modeling Fuel Preparation and Stratified Combustion in a Gasoline Direct Injection Engine” SAE Paper 1999-01-0175 1999
- Pontoppidan M. Gaviani G. Bella G. Rocco V. De Maio A. “Experimental and Numerical Approach to Injection and Ignition Optimization of Lean GDI Combustion Behavior” SAE Paper 1999-01-0173
- Stiesch, G. Merker, G.P. 2003
- Heywood J. “Internal Combustion Engines Fundamentals” McGraw-Hill New York 1988
- Salzgeber K Almer W. Sams T. Wimmer A. Graz 1995
- Schmidt S. Graz University of Technology 2005
- Onorati A. Ferrari G. 'Errico G. D “1D Unsteady Flows with Chemical Reactions in the Exhaust Duct-System of S.I. Engines: Predictions and Experiments” SAE Paper 2001-01-0939 2001
- Arnone L. Piaggio & C. S.p.A Kirchberger R. Technical University of Graz “Development of a direct injection two-stroke engine for scooters” ATA, International Conference Pisa November 2001
- Kirchberger R. Graz University of Technology 2003
- Durst Thams, Görg 2000 4
- Kaiser, Mochkaai Olesen 2005 4
- FIRE 8.3 User Guide: „CFD-WM UsersGuide” Graz 2005
- CD-Adapco: “User Guide”, StarCD Version 3.24 2004
- Schmidt, Winkler Schögl “Development of a Combustion Process for a High-Performance 2-Stroke Engine with Gasoline High-Pressure Direct Injection” SAE Powertrain&Fluid Tampa 2004
- Schmidt, Eichlseder Kirchberger, Ohrnberger Wagner, Nimmervoll „Gasoline Direct Injection with High-Performance Two-Stroke Application: Concepts, Experiences and Potential for the Future” SAE SETC 2004