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Three-Dimensional Computations of the Scavenging Process in an Opposed-Piston Engine
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Abstract
The effectiveness of scavenging, the displacement of residual combustion gases with fresh air, is examined in an advanced, high power-density diesel engine, consisting of a two-stroke, opposed-piston reciprocator with an ultra-high boost. KIVA-3, a three-dimensional code for modeling reactive flows with fuel injection, is used to study the effect of a variety design choices on scavenging. The parametric study includes the inclined angle of the intake ports, the exhaust port timing and size and the piston stroke-to-bore ratio. A baseline geometry of the opposed-piston engine is examined in detail, which models an existing mono-cylinder test rig. The baseline-design exhibits large asymmetries, nonsteady flow and large recirculation regions that degrade the scavenging. Significant improvement in the scavenging of the baseline design is observed with a uniform inclined angle of the inlet ports of about 20° and with a larger stroke-to-bore ratio (2.0 compared with 1.08).
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Zhu, Y., Savonen, C., Johnson, N., and Amsden, A., "Three-Dimensional Computations of the Scavenging Process in an Opposed-Piston Engine," SAE Technical Paper 941899, 1994, https://doi.org/10.4271/941899.Also In
References
- Amsden, A. A. O'Rourke, P. J. Butler, T. D. Meintzes K. Fansler, T. D. “Comparisons of Computed and Measured Three-Dimensional Velocity Fields in a Motored Two-Stroke Engine,” SAE Paper 920418
- Lai, Y. G. Przekwas, A. J. Sun, R. L. T. “Three-Dimensional Computation of the Scavenging Flow Process in a Motored Two-Stroke Engine,” SAE Paper 930499
- Carapanayotis, A. Salcudean, M. “The Effect of Inlet Velocity Orientation on the Scavenging Efficiency in a Uniflow Scavenged Engine,” Proceedings of the Fifteenth International Conference 1622 1633 1987
- Epstein, P. H. Reitz, R. D. Foster D. E. “Computations of a Two-Stroke Engine Cylinder and Port Scavenging Flows,” SAE Paper 910672
- Sammons, H. “The Napier Nomad Aircraft Diesel Engine,” SAE Paper 540320
- Johnston, R. P. “Variable Cycle Lightweight Diesel for Marine Application,” Naval Ship R&D CTR, 89-1623-CP AIAA
- Amsden, A. A. “KIVA-3: A KIVA Program with Block Structured Mesh for Complex Geometries,” Los Alamos National Laboratory report LA-12503-MS 1993
- Amsden, A. A. Butler, T. D. O'Rourke, P. J. “KIVA-II: A Computer Program for Chemically Reactive Flows with Sprays,” Los Alamos National Laboratory report LA-11560-MS 1989