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A CFD Study of Losses in a Straight-Six Diesel Engine
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 01, 1999 by SAE International in United States
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Using a previously validated and documented CFD methodology, this research simulated the flow field in the intake region (inlet duct, plenum, ports, valves, and cylinder) involving the four cylinders (#1, #3, #4, #6) of a straight-six IC engine. Each cylinder was studied with its intake valves set at high, medium and low valve lifts. All twelve viscous 3-D turbulent flow simulation models had high density, high quality computational grids and complete domains. Extremely fine grid density were applied for every simulation up to 1,000,000 finite volume cells. Results for all the cases presented here were declared “fully converged” and “grid independent”. The relative magnitude of total pressure losses in the entire intake region and loss mechanisms were documented here. It was found that the total pressure losses were caused by a number of flow mechanisms. The most important loss mechanisms included skin friction, separation, recirculation, reattachment, impingement, jet-to-jet interaction, high turbulence, and swirl and tumble type secondary flows. It was predicted that overall total pressure loss in the entire intake region decreased with increasing valve lift, and losses within the valve clearance region decreased with increasing valve lift. The comparisons of total pressure losses and flow fields were made between different simulations. An outstanding feature of the current study was the inclusion of physical mechanisms for valve lift variation of a single cylinder, and cylinder-to-cylinder variation of flows between different cylinders. From the comparisons, it was demonstrated that the results for all twelve cases had high internal consistency. By validation, the computed results obtained here showed consistent accuracy among all cylinders. Such consistency was obtained through careful application of the comprehensive methodology applied in this study.
CitationPan, W., Cui, Y., Leylek, J., Sommer, R. et al., "A CFD Study of Losses in a Straight-Six Diesel Engine," SAE Technical Paper 1999-01-0230, 1999, https://doi.org/10.4271/1999-01-0230.
- Bicen, A.F. Vafidis C. Whitelaw, J.H. 1981 “Steady and Unsteady Airflow through the Intake Valve of a Reciprocating Engine” ASME Journal of Fluids Engineering 107
- Brandstatter, W. 1988 “The Increasing Impact of Multidimensional Modelling on the Design and Development of High speed DI Diesel Engines” SAE Paper 881207
- Cui, Y. Pan, W. Leylek, J. H. Sommer, R. G. Jain, S. K. 1998 “Cylinder-to-Cylinder Variation of Losses in Intake Regions of IC Engines,” SAE Paper 981025
- Cui, Y. 1998 “A Computational Investigation of Cylinder-to-Cylinder Variation of Losses in IC Engines,” Department of Mechanical Engineering, Clemson University
- Dent, J.C. Chen, A. 1994 “Investigation of Steady Flow through a Curved Inlet Port.” SAE Paper 940522
- Godrie, P. Zellat, M. 1994 “Simulation of Flow Field Generated by Intake Port-Valve-Cylinder Configurations - Comparisons with Measurements and Applications” SAE Paper 940521
- Gosman, A.D. Ahmed, A.M.Y. 1987 “Measurement and Multidimensional Prediction of Flow in an Axisymmetric Port/Valve Assembly” SAE Paper 870592
- Kastner, L.J. William, T.J. White, J.B. 1964 “Poppet Inlet Valve Characteristics and Their Influence on the Induction Process” Proceedings of the Institute of Mechanical Engineers 178
- Khalighi, B. 1995 “Multidimensional In-Cylinder Flow Visualization in a Motored Engine” ASME Journal of Fluids Engineering 117
- Naser, J.A. Gosman, A.D. 1994 “Flow prediction in an Axisymmetric Inlet Valve/Port Assembly Using Variants of k-ε” Proceedings of the Institute of Mechanical Engineers 209
- Pan, W. 1998 “A Computational Study of Flow Physics in Intake Regions of IC Engines,” Department of Mechanical Engineering, Clemson University
- Tanaka, K. 1929 “Air Flow Through a Suction Valve of Conical Seat,” Aeronautical Research Institute Report Tokyo Imperial University
- Taylor, W. Leylek, J.H. Tran, L.T. Shinogle, R.D. Jain, S.K. 1997 “Advanced Computational Methods for Predicting Flow Losses in Intake Regions of Diesel Engines” SAE Paper 970639
- Walters, D. K. Leylek, J.H. 1996 “A Systematic Computational Methodology Applied to A Three-Dimensional Film-Cooling Flowfield” International Gas Turbine Congress and Exposition Birmingham, UK