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The Characteristics of Scavenging Flow in a Poppet-Valve Type 2-Stroke Diesel Engine by Using RSSV System
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Abstract
Optimization study is performed for the scavenging process as the first step for the development of a poppet-valve type automotive two-stroke diesel engine. The scavenging flow pattern is varied by the RSSV (rotatable shrouded scavenging valve) system, which was designed for application of a shroud valve to an actual engine. The scavenging flow is analyzed by flow visualization and numerical calculations under a steady condition. Water is used as the working fluid, instead of air for effective visualization of the flow pattern in the flow visualization study. More details in the scavenging characteristics are observed by a dye experiment, in which the dye path indicates the flow streamline in the cylinder. In the numerical study, three-dimensional flows are calculated by a modified version of KIVA-2 code, with a special technique to consider the valve and shroud shapes. The results show that a large shroud angle generates a center vortex in the cylinder by a strong reverse tumble flow, while a small shroud angle induces short-circuiting by a direct flow toward the exhaust valves. The shroud angle between 90 degree and 120 degree was found to be the optimal range for effective scavenging.
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Kang, K., Lee, J., Jeong, Y., Huh, K. et al., "The Characteristics of Scavenging Flow in a Poppet-Valve Type 2-Stroke Diesel Engine by Using RSSV System," SAE Technical Paper 960368, 1996, https://doi.org/10.4271/960368.Also In
References
- Heywood John B. Internal Combustion Engine Fundamentals 1988 McGraw Hill
- Duret Pierre “A New Generation of Two-Stroke Engine for the Future ?” International Seminar Nov. 1993 Rueil-Malmaison, France
- Nomura K. Nakamura N. “Development of a New Two-Stroke Engine with Poppet-Valves: Toyota S-2 Engine.” International Seminar Nov. 1993 Rueil-Malmaison, France
- Hundleby G. E. “Development of a Poppet-Valved Two-Stroke Engine - The Flagship Concept.” SAE paper 900802 1990
- Sato K. Nakano M. Ukawa H. “A Two-Stroke Cycle Gasoline Engine with Poppet Valves on the Cylinder Head.” SAE paper 901664 1990
- Blair Gordon P. The Basic Design of Two-Stroke Engines 1990 Society of automotive Engineers (SAE)
- Ekchian A. Hoult D. P. “Flow Visualization Study of the Intake Process of an Internal Combustion Engine.” SAE paper 790095 1979