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Effects of Intake Port Structures and Valve Timings on the Scavenging Process in a Two-Stroke Poppet Valve Diesel Engine
Technical Paper
2019-01-1169
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
The two-stroke operation is one of the most effective approaches to significantly increase the torque and power of a 4-stroke engine without the necessary requirement of intensifying the engine. Scavenging process is one of the key factors determining the performance of the two-stroke engine. In this work, a structure of top entry intake ports with poppet valves was employed on a 2-stroke single cylinder diesel engine with the conventional horizontal intake ports replaced. By this way, the reversed tumble flows in the cylinder were formed during the intake process to improve the scavenging performance of 2-stroke operation. In the meanwhile, the effects of valve timings and intake port structures on scavenging processes were estimated respectively through the1D and 3D simulation of the gas exchange process.
Results show that compared to the conventional horizontal intake port case, the reversed tumble flow created by the top-entry intake port led to a lower air short-circuiting rate and a higher scavenging efficiency. Furthermore, by advancing the exhaust valve opening the exhaust gas was discharged more sufficiently and the intake backflow was significantly reduced. Therefore, the charging efficiency and scavenging efficiency were improved with the reversed tumble. It was also found that with the constant valve timings by implementing the reversed tumble intake ports structure, the scavenging efficiency was increased from74% to 86%, and the trapping efficiency from 72% to 76%.
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Liu, W., Zhang, Y., Yu, B., Li, Y. et al., "Effects of Intake Port Structures and Valve Timings on the Scavenging Process in a Two-Stroke Poppet Valve Diesel Engine," SAE Technical Paper 2019-01-1169, 2019, https://doi.org/10.4271/2019-01-1169.Data Sets - Support Documents
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References
- Attard , W. , Konidaris , S. , Toulson , E. , and Watson , H. The Feasibility of Downsizing a 1.25 Liter Normally Aspirated Engine to a 0.43 Liter Highly Turbocharged Engine SAE Technical Paper 2007-24-0083 2007 10.4271/2007-24-0083
- Zhang , Y. , Wang , Z. , Bai , H. , Guo , C. et al. The Reduction of Mechanical and Thermal Loads in a High-Speed HD Diesel Engine Using Miller Cycle with Late Intake Valve Closing SAE Technical Paper 2017-01-0637 2017 10.4271/2017-01-0637
- Xue , Q. , He , B. , and Zhao , H. The Upper-Load Extension of a Boosted Direct Injection Poppet Valve Two-Stroke Gasoline Engine SAE Technical Paper 2016-01-2039 2016 10.4271/2016-01-2039
- Hofbauer , P. Opposed Piston Opposed Cylinder (OPOC) Engine for Military Ground Vehicles SAE Technical Paper 2005-01-1548 2005 10.4271/2005-01-1548
- Franke , M. , Huang , H. , Liu , J. , Geistert , A. et al. Opposed Piston Opposed Cylinder (OPOCâ„¢) 450hp Engine; Performance Development by CAE Simulation and Testing SAE Technical Paper 2006-01-0277 2006 10.4271/2006-01-0277
- Naik , S. , Johnson , D. , Koszewnik , J. , Fromm , L. et al. Practical Applications of Opposed Piston Engine Technology to Reduce Fuel Consumption and Emissions SAE Technical Paper 2013-01-2574 2013 10.4271/2013-01-2574
- Pugnali , L.D. and Chen , R. Feasibility Study of Operating 2-Stroke Miller Cycles on a 4-Stroke Platform through Variable Valve Train SAE Technical Paper 2015-01-1974 2015 10.4271/2015-01-1974
- Hundleby , G.E. Development of a Poppet-Valved Two-Stroke Engine-the Flagship Concept SAE Technical Paper 900802 1990 10.4271/900802
- Stokes , J. , Hundleby , G.E. , Lake , T.H. , Christie , M. et al. Development Experience of a Poppet-Valved Two-Stroke Flagship Engine SAE Technical Paper 920778 1992 10.4271/920778
- Nakano , M. , Sato , K. , and Ukawa , H. A Two-Stroke Cycle Gasoline Engine with Poppet Valves in the Cylinder Head SAE Technical Paper 901664 1990 10.4271/901664
- Sato , K. , Ukawa , H. , and Nakano , M. A Two-Stroke Cycle Gasoline Engine with Poppet Valves in the Cylinder Head-Part II SAE Technical Paper 920780 1992 10.4271/920780
- Ukawa , H. , Nakano , M. , and Sato , K. A Two-Stroke Cycle Gasoline Engine with Poppet Valves in the Cylinder Head-Part III: An Application of Gaseous Fuel Direct Injection System SAE Technical Paper 930983 1993 10.4271/930983
- 2014
- Zhang , Y. and Zhao , H. Investigation of Combustion, Performance and Emission Characteristics of 2-Stroke and 4-Stroke Spark Ignition and CAI/HCCI Operations in a DI Gasoline Appl Energy 130 244 255 2014 10.1016/j.apenergy.2014.05.036
- Osborne , R.J. , Strokes , J. , Lake , T.H. , Carden , P.J. et al. Development of a Two-Stroke/Four-Stroke Switching Gasoline-the 2/4 SIGHT Concept SAE Technical Paper 2005-01-1137 2005 10.4271/2005-01-1137
- Li , Z. , He , B. , and Zhao , H. Influences of Intake Ports and Pent-Roof Structures on the Flow Characteristics of a Poppet-Valved Two-Stroke Gasoline Engine International J of Engine Research 17 10 1077 1091 2016
- Lu , M. , Xu , Z. , and Liu , S. Investigation of Tumble Intake System of 2-Valves S.I. Engine on a Steady Flow Rig J Combust Sci Technol 2 3 270 278 1996
- Philipp , A. , Markus , J. , Stefan , P. , Andre , B. et al. Effect of Intake Port Design on the Flow Field Stability of a Gasoline DI Engine SAE Technical Paper 2011-01-1284 2011 10.4271/2011-01-1284
- Oliver , S. , Hermann , E. , Stefan , S. , Stefan , L. et al. Design of a Tumble-Orientated Intake Port Layout for a Gasoline Combustion Process Used in Power Sport Application SAE Technical Paper 2011-32-0589 2011 10.4271/2011-32-0589
- Selvaraj , B. , Sridhara , S.N. , Indraprakash , G. , Senthilkumarv , A. et al. Effects of Intake Port Geometry on the Performance of an SI Engine SAE Technical Paper 2011-32-0506 2011 10.4271/2011-32-0506
- Heywood , J.B. Internal Combustion Engine Fundamentals New York McGraw-Hill 1988 237 238