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Laser Doppler Velocimetry Measurements in Valved and Ported Engines
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English
Abstract
Measurements are presented of bulk velocity and its cyclic variation and of turbulence intensity in IC engines with combustion chambers of open shape. Engines with both ported* and valved intakes were tested. The ported engine was tested both with and without swirl and the valved engine without swirl only. The ported engine was motored at 1200, 1800 and 2400 RPM and the valved engine at 600, 1200 and 1800 RPM. In both engines the shape of the combustion chamber was such as not to introduce strong organized gas motion during compression. Thus the in-cylinder gas motion, including turbulence, was due primarily to the intake process. The measurements were made using laser Doppler velocimetry at data rates which were sufficiently high to determine the bulk velocity in each cycle and thereby separate the cyclic fluctuations of the bulk velocity from the turbulence. Such measurements are called cycle-resolved and have not previously been made in either valved or ported engines at practical engine speeds using LDV. The measurements were made at numerous spatial locations in the ported engine and at a single location in the valved engine, in both cases on a plane centered within the clearance height over a crankangle interval of sixty-four degrees around TDC.
It is shown that the ensemble averaged velocity is proportional to engine speed in the ported engine with swirl, whereas no such trend was found in either the ported or valved engines without swirl. The cyclic variation of the bulk velocity is shown to increase with engine speed and to decrease with swirl; trends which are consistent with the results of other studies of cyclic peak pressure and flame propagation variations. An ensemble averaged analysis of the turbulence, which includes the contribution of the cyclic variation in the bulk velocity, was found to overestimate the cycle resolved turbulence intensity by as much as 100% in the ported engine without swirl and by as much as 300% in the valved engine without swirl; however, in the case of the ported engine with swirl this difference was less than 10%. In all cases the turbulence intensity was found to be nearly proportional to engine speed and in the ported engine, with and without swirl, the turbulence intensity was found to be approximately homogeneous. In both the valved and ported engines without swirl, TDC turbulence was also found to be isotropic within ±20%. These findings support the hypothesis that, for open combustion chambers, different intake designs influence the intensity of the TDC turbulence (and, possibly, its scale) but not its homogeneity, isotropy or proportionality to engine speed.
Authors
- T.-M. Liou - Dept. of Mechanical and Aerospace Engineering, Princeton University
- M. Hall - Dept. of Mechanical and Aerospace Engineering, Princeton University
- D.A. Santavicca - Dept. of Mechanical and Aerospace Engineering, Princeton University
- F.V. Bracco - Dept. of Mechanical and Aerospace Engineering, Princeton University
Citation
Liou, T., Hall, M., Santavicca, D., and Bracco, F., "Laser Doppler Velocimetry Measurements in Valved and Ported Engines," SAE Technical Paper 840375, 1984, https://doi.org/10.4271/840375.Also In
References
- Semenov E.S. Studies of turbulent gas flow in piston engines Otedelenie Technicheskikh Nauk 8 1958
- Winsor R.E. Patterson D.J. Mixture turbulence - a key to cyclic combustion variation SAE Paper No. 730086 1973
- Dent J.C. Salama N.S. The measurement of the turbulence characteristics in an internal combustion engine cylinder SAE Paper No. 750886 1975
- Lancaster D.R. Effects of engine variables on turbulence in a spark-ignition engine SAE Paper No. 760159 1976
- Lancaster D.R. Krieger R.B. Sorenson S.C. Hull W.L. Effects of turbulence on spark-ignition engine combustion SAE Paper No. 760160 1976
- Witze P.O. Measurements of the spatial distribution and engine speed dependence of turbulent air motion in an I.C. engine SAE Paper No. 770220 1977
- Asanuma T. Obokata T. Gas velocity measurements of a motored and firing engine by laser anemometry SAE Paper No. 790096 1979
- Brandl F. Reverencic I. Carellieri 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
- Rask R.B. Laser Doppler anemometer measurements in an internal combustion engine SAE Paper No. 790094 1979
- Cole J.B. Swords M.D. Optical studies of turbulence in an internal combustion engine Seventeenth Int'l. Combustion Symposium 1978
- Groff E.G. Matekunas F.A. The nature of turbulent flame propagation in a homogeneous spark-ignited engine SAE Paper No. 800133 1980
- Witze P.O. Influence of air motion variation on the performance of a direct injection stratified charge engine Stratified Charge Automotive Engines , Inst. of Mech. Eng. Conf. Publication 1980-9 1980
- Smith J.R. Turbulent flame structure in a homogeoneous-charge engine SAE Paper No. 820043 1982
- Smith J.R. The influence of turbulence on flame structure in an engine ASME Annual Winter Meeting Phoenix, Arizona November 1982
- Liou T.-M. Laser Doppler velocimetry measurements in valved and ported engines Ph.D. Thesis No. 1602 Princeton University May 1983
- Witze P.O. A critical comparison of hotwire anemometry and laser Doppler velocimetry for I.C. engine applications SAE Paper No. 800132 1980
- Liou T.-M. Santavicca D.A. Cycle resolved turbulence measurements in a ported engine with and without swirl SAE International Congress Paper No. 830419 1983
- Glass M. Kennedy I. An improved seeding method for high temperature laser Doppler velocimetry Combustion and Flame 29 3 1977
- Agarwal J.K. Fingerson L.M. Evalaution of various particles for their suitability as seeds in laser velocimetry Laser Velocimetry and Particle Sizing Thompson H.D. Stevenson W.H. Hemisphere Publishing Co. 1979
- Bowditch F.W. A new tool for combustion research: a quartz piston engine SAE Paper No. 150B March 1960
- Grasso F. Bracco F.V. Computed and measured turbulence in axisymmetric reciprocating engines AIAA J. 21 4 601 1983
- Hayder E. Varma A.K. Bracco F.V. Comparisons of calculated and measured flows in ported and valved IC engines
- Rask R.B. Comparison of window, smooth-ensemble and cycle-by-cycle data reduction techniques for laser-Doppler anemometer measurements of in-cylinder velocity Fluid Mechanics of Combustion Systems Morel T. Lohmann R.P. Rackley J.M. New York American Society of Mechanical Engineers 1981
- Reynolds W.C. Modeling of fluid motions in engines - an introductory overview Combustion Modeling in Reciprocating Engines Mattavi J.N. Amann C.A. Plenum Press 1980
- Wakisaka T. Hamamoto Y. Ohigasi S. Hashimoto M. Measurements of air swirl and its turbulence characteristics in the cylinder of an internal combustion engine Paper No. C91/79 51 62 I. Mech. Eng. 1979
- Liou T.-M. Santavicca D.A. Cycle resolved LDV measurements in a motored IC engine Engineering Applications of Laser Velocimetry Coleman H.W. Pfund P.A. New York American Society of Mechanical Engineers 1982
- Liou T.-M. Santavicca D.A. Bracco F.V. “Turbulence measurements in a ported IC engine Int'l Symposium on Applications of Laser-Doppler Anemoetry to Fluid Mechanics Lisbon, Portugal July 1982
- Liou T.-M. Santavicca D.A. Cycle resolved turbulence measurements in a motored IC engine - spectral analysis ASME Journal of Fluids Engineering
- Young M.C. Cyclic dispersion in the homogeneous-charge spark-ignition engine - a literature survey SAE Paper No. 810020 1981
- Patterson D.J. Cylinder pressure variations, a fundamental combustion problem SAE Transactions 75 660129 1966
- Barton R.K. Kenomuth D.K. Lestz S.S. Mayer W.Z. Cycle-by-cycle, variations of a spark ignition engine - a statistical analysis SAE Paper No. 700488 1970
- Peters B.D. Borman G.L. Cyclic variations and average burning rates in a S.I. engine SAE Paper No. 700064 1970
- Vichnievsky R. Combustion in petrol engines Proceedings on the Joint Conference on Combustion, IME-ASME 1955
- Harrow G.A. Orman P.L. A study of flame propagation and cyclic dispersion in a spark-ignition engine Advances in Automotive Engineering Pergamon Oxford 1966
- Broeze J.J. Combustion in Internal combustion engine, II. The spark-ignition engine Engineering 169 1950