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Schlieren Measurements of the ECN-Spray A Penetration under Inert and Reacting Conditions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 16, 2012 by SAE International in United States
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In the wake of the Turbulent Nonpremixed Flames group (TNF) for atmospheric pressure flames, an open group of laboratories belonging to the Engine Combustion Network (ECN) agreed on a list of boundary conditions -called “Spray A”- to study the free diesel spray under steady-state conditions. Such conditions are relevant of a diesel engine operating at low temperature combustion conditions with moderate EGR, small nozzle and high injection pressure. The objective of this program is to accelerate the understanding of diesel flames, by applying each laboratory's knowledge and skills to a specific set of boundary conditions, in order to give an extensive and reliable experimental database to help spray modeling.
In the present work, “Spray A” operating condition has been achieved in a constant pressure, continuous flow vessel. Schlieren high-speed imaging has been conducted to measure the spray penetration under evaporative conditions. The first step of this work was to address the effect of the schlieren setup variables on the resulting image. A comprehensive and conceptual approach of the technique in the context of a diesel spray is provided and evidences the need to control both the beam collection and the Fourier filtering in a focused schlieren setup. The experimental work consisted in varying the light-source diameter and the collection angle in the Fourier plane with the objective to optimize the optical arrangement with regard to image processing. Images of the plane of Fourier were also collected to help the analysis. The results show that the refraction angle of the air/fuel mixture exceeds 250 mrad while it is only around 4 mrad for the dense gas surrounding the spray. An optical arrangement in agreement with these measurements is proposed and allows reliable image processing for the measurement of spray penetration under both inert and reacting conditions.
Regarding the comparison of measured inert and reactive spray penetration, the reactive spray appears to penetrate faster than the inert one. Predictions of a 1D model have been compared to experimental measurements of spray penetration. Results show that the flow tends to accelerate along the inert-to-reacting transition, due to the drop in local density. However, this trend is dampened to some extent due to the expansion in radial direction, which is shown experimentally as an increase of the spreading angle. In the end, the first effect is dominating the evolution of the reacting spray, and reacting penetration is faster than the inert one.
CitationPastor, J., Payri, R., Garcia-Oliver, J., and Nerva, J., "Schlieren Measurements of the ECN-Spray A Penetration under Inert and Reacting Conditions," SAE Technical Paper 2012-01-0456, 2012, https://doi.org/10.4271/2012-01-0456.
- Pickett, L. Hoogterp, L. “Fundamental Spray and Combustion Measurements of JP-8 at Diesel Conditions,” SAE Int. J. Commer. Veh. 1 1 108 118 2009 10.4271/2008-01-1083
- Pickett, L. Kook, S. Williams, T. “Visualization of Diesel Spray Penetration, Cool-Flame, Ignition, High-Temperature Combustion, and Soot Formation Using High-Speed Imaging,” SAE Int. J. Engines 2 1 439 459 2009 10.4271/2009-01-0658
- Payri, R. Salvador, F.J. Gimeno, J. Bracho, G. A new methodology for correcting the signal cumulative phenomenon on injection rate measurements Experimental techniques 32 1 46 49 2008
- Payri, R. Garcia, J.M. Salvador, F.J. Gimeno, J. Using spray momentum flux measurements to understand the influence of diesel nozzle geometry on spray characteristics Fuel 84 551 561 2005
- Pastor, J.V. López, J.J. García, J.M. Pastor, J.M. A 1D Model for the Description of Mixing-Controlled Inert Diesel Sprays Fuel 87 2871 2885 2008
- Desantes, J.M. Pastor, J.V. García-Oliver, J.M. Pastor, J.M. A 1D Model for the Description of Mixing-Controlled Reacting Diesel Sprays Combustion and Flame 156 234 249 2009
- Faeth, G.M. Evaporation and combustion of sprays Prog. Energ. Combust. Sci. 9 1 76 1983
- Reid, R. C. Prausnitz, J. M. Poiling, B. E. The Properties of Gases and Liquids McGraw-Hill New York 1987
- Burke, S.P. Schumann, T.E. Ind. Eng. Chem. 20 10 998 1004 1928
- Settles, G.S. Schlieren and Shadowgraph Techniques Springer-Verlag 2001
- Pastor, J. García, J. Pastor, J. Zapata, L. “Evaporating Diesel Spray Visualization using a Double- pass Shadowgraphy/Schlieren imaging,” SAE Technical Paper 2007-24-0026 2007 10.4271/2007-24-0026
- Naber, J. Siebers, D. “Effects of Gas Density and Vaporization on Penetration and Dispersion of Diesel Sprays,” SAE Technical Paper 960034 1996 10.4271/960034
- Bermúdez, V. García, J. Juliá, E. Martínez, S. “Engine with Optically Accessible Cylinder Head: A Research Tool for Injection and Combustion Processes,” SAE Technical Paper 2003-01-1110 2003 10.4271/2003-01-1110
- Payri, F. Pastor, J. Nerva, J. Garcia-Oliver, J. “Lift-Off Length and KL Extinction Measurements of Biodiesel and Fischer-Tropsch Fuels under Quasi-Steady Diesel Engine Conditions,” SAE Int. J. Engines 4 2 2278 2297 2011 10.4271/2011-24-0037
- Proceedings of the ECN Workshop 13 14 May 2011 Ventura, USA http://www.sandia.gov/ecn/proceed/proceedECN1.php
- Pickett, L. Genzale, C. Bruneaux, G. Malbec, L. et al. “Comparison of Diesel Spray Combustion in Different High-Temperature, High-Pressure Facilities,” SAE Int. J. Engines 3 2 156 181 2010 10.4271/2010-01-2106
- Musculus, M. Kattke, K. “Entrainment Waves in Diesel Jets,” SAE Int. J. Engines 2 1 1170 1193 2009 10.4271/2009-01-1355
- Musculus, M.P.B. Entrainment waves in decelerating transient, turbulent jets J. Fluid Mech. 638 117 140 2009
- Pickett, L. Manin, J. Genzale, C. Siebers, D. et al. “Relationship Between Diesel Fuel Spray Vapor Penetration/Dispersion and Local Fuel Mixture Fraction,” SAE Int. J. Engines 4 1 764 799 2011 10.4271/2011-01-0686