This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
The Effect of In-Cylinder Flow Processes (Swirl, Squish and Turbulence Intensity) on Engine Efficiency — Model Predictions
Annotation ability available
Sector:
Language:
English
Abstract
A computer simulation for the performance of a four-stroke spark-ignition engine is used to assess the effects of in-cylinder flow processes on engine efficiency. The engine simulation model is a thermodynamic model coupled to submodels for the various physical processes of in-cylinder swirl, squish and turbulent velocities, heat transfer and flame propagation.
The swirl and turbulence models are based on an integral formulation of the angular momentum equation and a K-ε turbulence model, These models account for the effects of changes in geometry of the intake system and the chamber design on in-cylinder flow processes. The combustion model is an entrainment burn-up model applicable to the mixing controlled region of turbulent flame propagation. The flame is assumed to propagate spherically from one or two spark plug locations. A heat transfer model that is dependent upon the turbulence level is used to compute the heat loss from the unburned and burned gases. These submodels are calibrated from experimental data.
In this paper a combustion system featuring high and low swirl generating ports, a flat head and various piston designs is investigated. A parameter study is conducted to determine the effects of in-cylinder geometry on burn duration, heat transfer and fuel consumption. These results indicate that swirl, squish and turbulence intensity levels can be varied to produce a minimum in fuel consumption for the conditions examined. In addition, the isolated effect of the turbulence intensity on engine efficiency is presented for various EGR levels.
Recommended Content
Authors
Topic
Citation
Davis, G. and Borgnakke, C., "The Effect of In-Cylinder Flow Processes (Swirl, Squish and Turbulence Intensity) on Engine Efficiency — Model Predictions," SAE Technical Paper 820045, 1982, https://doi.org/10.4271/820045.Also In
References
- Blumberg, P. N. Lavoie, G. A. Tabaczynski, R. J. “Phenomenological Models for Reciprocating Internal Combustion Engines,” Progress in Energy Combustion Science 5 123 1979
- Heywood, J. B. “Engine Combustion Modeling-An Overview,” in” Combustion Modeling in Reciprocating Engines Mattavi J. N. Amann, C. A. Plenum Press 1980
- Boni, A. A. “Numerical Simulation of Flame Propagation in Internal Combustion Engines: A Status Report,” SAE Paper No. 780316 1978
- Reynolds, W. C. “Modelling of Fluid Motions in Engines-An Introductory Overview,”
- Gosman, A. D. Watkins, A. P. “A Computer Prediction Method for Turbulent Flow and Heat Transfer in Piston/Cylinder Assemblies,” Proc. Sym. on Turbulent Shear Flows Penn St. Univ. 1977
- Gosman, A. D. Johns, R. J. R. “Development of a Predictive Tool for In-Cylinder Gas Motion in Engines,” SAE Paper No. 780315 1978
- Ahmadi-Befrui, B. Gosman, A. D. Lockwood, F. C. Watkins, A. P. “Multidimensional Calculation of Combustion in an Idealized Homogeneous Charge Engine: A Progress Report,” SAE Paper No. 810151 1981
- Bracco, F. V. “Introducing a New Generation of More Detailed and Informative Combustion Models,” SAE Transactions 1975 84
- Syed, S. A. Bracco, F. V. “Further Comparisons of Computed and Measured Divided Chamber Engine Combustion,” SAE Paper No. 790247 1979
- Ramos, J. I. Sirignano, W. A. “Axi-symmetric Flow Model With and Without Swirl in a Piston-Cylinder Arrangement With Idealized Valve Operation,” SAE Paper No. 800284 1980
- Morse, A. P. Whitelaw, J. H. Yianneskis, M. “Turbulent Flow Measurements by Laser-Doppler Anemometry in Motored Piston-Cylinder Assemblies,” Jour. Fluid Eng. 101 208 1979
- Hutchinson, P. Morse, A. P. Whitelaw, J. H. “Velocity Measurement in Motored Engines-Experience and Prognosis,” SAE Paper No. 780061 1978
- Boni, A. A. Chapman, M. Cook, J. L. Schneyer, G. I. “Computes Simulation of Combustion in Stratified Charge Engines,” 16th Symposium on Combustion 1976
- Chapman, M. “Two Dimensional Numerical Simulation of Inlet Manifold Flow in a Four Cylinder Internal Combustion Engine,” SAE Paper No. 790244 1979
- Hirt, C. W. Amsden, A. A. Cook, J. L. “An Arbitrary Lagrangian-Eulerian Computing Method for all Flow Speeds,” J. Corap. Phys. 14 227 1974
- Butler, T. D. Cloutman, L. D. Dukowicz, J. K. Ramshaw, J. C. Krieger, R. B. “Toward a Comprehensive Model for Combustion in a Direct-Injection Stratified Charge Engine,”
- Krieger, R. B. “Application of Engine Combustion Models-An Introductory Overview,”
- Blizard, N. C. Keck, J. C. “Experimental and Theoretical Investigation of Turbulent Burning Model for Internal Combustion Engines,” SAE Paper No. 740191 1974
- Tabaczynski, R. J. Ferguson, C. R. Radhakrishnan, K. “A Turbulent Entrainment Model for Spark Ignition Engine Combustion,” SAE Paper No. 770647 1977
- Hires, S. D. Tabaczynski, R. J. Novak, J. M. “The Prediction of Ignition Delay and Combustion Intervals for a Homogeneous Charge, Spark Ignition Engine,” SAE Paper No. 780232 1978
- Spalding, D. B. “Development of the Eddy-Breakup Model of Turbulent Combustion,” 16th Int. Symposium of Combustion 1657 1976
- Spalding, D. B. “A General Theory of Turbulent Combustion, The Lagrangian Aspects,” AIAA 15th Aerospace Science Meeting 1977
- Witze, P. O. “A Critical Comparison of Hot-Wire Anemometry and Laser Doppler Velocimetry for I.C. Engine Applications,” SAE Paper No. 800132 1980
- Witze, P. O. “Influence of Air Motion Variation on the Performance of a Direct Injection Stratified Charge Engine,” Proc. Instn. Mech. Engrs. c394 80 1980
- Rask, R. B. “Laser Doppler Anemometer Measurements in an Internal Combustion Engine,” SAE Paper No. 790094 1979
- Asanuiaa, T. Obokata, T. “Gas Velocity Measurements of a Motored and Firing Engine by Laser Anemometry,” SAE Paper No. 790096 1979
- Fitzgeorge, D. Allison, J. L. “Air Swirl in a Road Vehicle Diesel Engine,” Proc. Instn. Mech. eng. 25 1962
- Dent, J. C. Derham, J. A. “Air Motion in a Four-Stroke Direct Injection Diesel Engine,” Proc. Instn. Mech. Engrs. 188 21 269 1974
- Davis, G. C. Kent, J. C. “Comparison of Model Calculations and Experimental Measurements of the Bulk Cylinder Flow Processes in a Motored Proco Engine,” SAE Paper No. 790290 1979
- Kido, H. Wakuri, Y. Ono, S. Murase, E. “Prediction of In-Cylinder Gas Motion in Engines by an Energy Method,” SAE Paper No. 800985 1980
- Borgnakke, C. Davis, G. C. Tabaczynski, R. J. “Predictions of In-Cylinder Swirl Velocity and Turbulence Intensity for an Open Chamber Cup in Piston Engine,” SAE Paper No. 810224 1981
- Hoult, D. P. Wong, V. W. “The Generation of Turbulence in an Internal Combustion Engine,”
- Hoult, D. P. Wong, V. W. “Rapid Distortion theory Applied to Turbulent Combustion,” SAE Paper No. 790357 1979
- Borgnakke, C. Arpaci, V. Tabaczynski, R. J. “A Model for the Instantaneous Heat Transfer and Turbulence in a Spark Ignition Engine,” SAE Paper no. 800287 1980
- Launder, B. E. Spalding, D. B. “Lecturers in Mathematical Models of Turbulence,” Academic Press 1972
- Wolfsthein, M. “The Velocity and Temperature Distribution in One-Dimensional Flow with Turbulence Augmentation and Pressure Gradient,” Int. Jour. Heat Mass Transfer 12 301 1969
- Woschni, G. “A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine,” SAE Paper No. 670931 1967
- Annand, W. J. D. “Heat Transfer in the Cylinders of Reciprocating Internal Combustion Engines,” Proc. Instn. Mech. Eng. 477 973 1963
- Annand, W. J. Ma, T. H. “Instantaneous Heat Transfer Rates to the Cylinder Head Surface of a Small Compression-Ignition Engine,” Proc. Instn. Mech. Eng. 185 976 1970-71
- Lockwood, F. C. Naguib, A. S. “The Prediction of the Fluctuations in the Properties of Free, Round-Jet, Turbulent Diffusion Flames,” Combustion and Flame 24 109 1975
- Pope, S. B. “Monte Carlo Calculations of Premixed Turbulent Flames,” 16th Int. Sym. on Combustion 1981
- Van Tiggelen A. Deckers, J. “Chain Branching and Flame Propagation,” 6th Int. Sym. on Combustion 1957
- Brandl, F. Reverencic, I. Cartellieni W. Dent, J. C. “Turbulent Air Flow in the Combustion Bowl of a D. I. Diesel Engine and Its Effect on Engine Performance,” SAE Paper No. 790040 1979
- Tabaczynski, R. J. Trinker F. H. Shannon, B. A. S. “Further Refinement and Validation of a Turbulent Flame Propagation Model for Spark-Ignition Engines,” Combustion and Flame 39 111-121 1980
- Tanabe, S. Hamamoto, Y. Ohigashi, S. “Swirl in a Four Stroke Cycle Engine Cylinder,” J.S.M.E. 21 152 287 1978
- Lee, W. Schafer, H. J. Schapertone, H. “Investigation of High Compression Ratio SI Engine by a Two Dimensional Model,” 5th Int’l Automotive Propulsion System Symp. 1980
- Nagayama, I. Araki, Y. Lioka, Y. “Effects of Swirl and Squish on S.I. Engine Combustion and Emission,” SAE Paper No. 770217 1977