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Modeling of the Natural Gas Injection Process in a Two-Stroke Diesel Engine
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Abstract
A computational fluid dynamics (CFD) study was carried out on a two-stroke uni-flow diesel engine adapted to operate on direct-injected natural gas (NG) with a diesel pilot ignition source. A medium pressure injector was used to inject the natural gas through the cylinder wall slightly above the intake ports during the gas exchange period. The CFD study concentrated on the effect of the injector orientation on the loss of fuel during scavenging and on in-cylinder mixing of the NG fuel. A three-dimensional CFD model of the cylinder configuration was created in order to simulate the scavenging, NG injection and mixing periods during the cycle. A parametric study of the orientation of the NG injector was performed in order to find the optimal design, within manufacturing constraints, which would minimize HC emissions. It was found that the amount of NG fuel lost during the scavenging period could be reduced if the NG injector is directed downward, toward the bowl in the piston. Also, orientating the NG injector tangentially (off the radial line) can reduce the loss of fuel, although to a smaller degree than directing it toward the piston crown. The best configuration, which would require minimal hardware changes, produced over a 50% reduction in fuel loss compared to a baseline configuration.
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Jeske, F., Jennings, M., and Welch, A., "Modeling of the Natural Gas Injection Process in a Two-Stroke Diesel Engine," SAE Technical Paper 920192, 1992, https://doi.org/10.4271/920192.Also In
References
- ANDREWS, M. J. BRACCO, F. V. “The Use of Intake and Exhaust Measurements with Computer Simulations to Investigate the Evolution of the Internal Flow Field in a Ported Engine,” SAE Paper 910262 1991
- CHARLTON, S. J. JAGER, D. J. WILSON, M. SHOOSHTARIAN, A. “Computer Modelling and Experimental Investigation of a Lean Burn Natural Gas Engine,” SAE Paper No. 900228 1990
- DIWAKAR, R. “Three-Dimensional Modeling of the In-Cylinder Gas Exchange Processes in a Uniflow-Scavenged Two-Stroke Engine,” SAE Paper No. 870596 1987
- GREEN, C. “6V-92TA Duel Fuel Bus Engine with TWI,” Ortech Report No. 5783/16 February 1991
- JOHNS, R. J. R. “Progress in the Development of a Detailed Model for Diesel Combustion,” Proceedings of the Diagnostic and Modeling of Combustion in IC Engines, COMODIA 90 1990
- JOHNS, R. J. R. JONES, P. M. “Computer Modelling of the Flow in a Lean Burn Natural Gas Engine” I. Mech. E. “Computers in Engine Technology” Conference Cambridge, UK September 1991
- LAUNDER, B. E. SPALDING, D. B. Mathematical Models of Turbulence Academic Press 1972
- MOREL, T. KERIBAR, R. BLUMBERG, P. N. “A New Approach to Integrating Engine Performance and Component Design Analysis Through Simulation,” SAE Paper No. 880131 1988
- MOREL, T. FLEMMING, M. F. LAPOINTE, L. A. “Characterization of Manifold Dynamics in the Chrysler 2.2 S.I. Engine by Measurements and Simulation,” SAE Paper No. 900679 1990
- REYNOLDS, W. C. “Modeling of Fluid Motions in Engines, An Introductory Overview,” Proceedings of the Combustion Modeling in Reciprocating Engines GMR Laboratories 1978