This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Injected Droplet Size Effects on Diesel Spray Results with RANS and LES Turbulence Models
Technical Paper
2015-01-0925
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
Injection spray dynamics is known to be of great importance when modeling turbulent multi-phase flows in diesel engines. Two key aspects of spray dynamics are liquid breakup and penetration, both of which are affected by the initial sizes of the injected droplets. In the current study, injection of liquid n-heptane is characterized with initial droplet sizes with diameters on the order of 0.10 - 0.25 nozzle diameters. This is done for a Reynolds Averaged Navier-Stokes (RANS) RNG k-ε turbulence model with a minimum grid size of 125 μm and for a Large Eddy Simulations (LES) viscosity turbulence model with a minimum grid size of 62.5 μm. The results of both turbulence models are validated against non-reacting experimental data from the Engine Combustion Network (ECN).
The results show that the injected droplet sizes have a significant impact on both liquid and vapor penetration lengths. In addition, the primary breakup parameter B1 and the sizes of the injected droplets are shown to be equally important for predicting the liquid penetration length. Both turbulence models match experimental data of liquid penetration for injected droplets with diameters of 17.5 μm. However, the vapor penetration is under-predicted at this diameter which can be addressed by decreasing the droplet-per-parcel ratio. Fuel mass fractions and temperature gradients are in good agreement with experiment.
Recommended Content
Authors
Topic
Citation
Elmtoft, E., Cheng, A., Killingsworth, N., and Whitesides, R., "Injected Droplet Size Effects on Diesel Spray Results with RANS and LES Turbulence Models," SAE Technical Paper 2015-01-0925, 2015, https://doi.org/10.4271/2015-01-0925.Also In
References
- Som , S. , Senecal , P. K. , and Pomraning , E. Comparison of RANS and LES Turbulence Models against Constant Volume Diesel Experiments ILASS Americas, 24 th Annual Conference on Liquid Atomization and Spray Systems San Antonio, TX, USA May 2012
- Hu , Z. , Somers , L. M. T. , Davies , T. , McDougall , A. et al. A Study of Liquid Fuel Injection and Combustion in a Constant Volume Vessel at Diesel Engine Conditions Fuel 107 2013 63 73 http://dx.doi.org/10.1016/j.fuel.2013.01.043
- Som , S. , D'Errico , G. , Longman , D. , and Lucchini , T. Comparison and Standardization of Numerical Approaches for the Prediction of Non-reacting and Reacting Diesel Sprays SAE Technical Paper 2012-01-1263 2012 10.4271/2012-01-1263
- Pang , K. , Jangi , M. , Bai , X. , and Schramm , J. Investigation of Chemical Kinetics on Soot Formation Event of n-Heptane Spray Combustion SAE Technical Paper 2014-01-1254 2014 10.4271/2014-01-1254
- Cho , H. and Kim , W. Numerical Simulation of Diesel Spray Combustion in a Constant Volume Chamber by Eulerian and Lagrangian Conditional Moment Closure Models SAE Technical Paper 2013-01-1600 2013 10.4271/2013-01-1600
- Som , S. , Aggarwal , S. K. Effects of Primary Breakup Modeling on Spray and Combustion Characteristics of Compression Ignition Engines Combustion and Flame 157 2010 1179 1193 10.1016/j.combustflame.2010.02.018
- Lucchini , T. , D'Errico , G. , Ettorre , D. , and Ferrari , G. Numerical Investigation of Non-Reacting and Reacting Diesel Sprays in Constant-Volume Vessels SAE Int. J. Fuels Lubr. 2 1 966 975 2009 10.4271/2009-01-1971
- Xue , Q. , Som , S. , Senecal , P. K. , and Pomraning , E. A Study of Grid Resolution and SGS Models for LES under Non-reacting Spray Conditions ILASS Americas, 25 th Annual Conference on Liquid Atomization and Spray Systems Pittsburgh, PA, USA May 2013
- Som , S. , Longman , D. , Luo , Z. , Plomer , M. et al. Simulating Flame Lift-Off Characteristics of Diesel and Biodiesel Fuels Using Detailed Chemical-Kinetic Mechanisms and Large Eddy Simulation Turbulence Model Journal of Energy Resources Technology 134 2012 10.1115/1.4007216
- Senecal , P. K. , Pomraning , E. , Xue , Q. , Som , S. et al. Large Eddy Simulation of Vaporizing Sprays Considering Multi-Injection Averaging And Grid-Convergent Mesh Resolution Proceedings of the ASME 2013 Internal Combustion Engine Division Fall Technical Conference Dearborn, MI, USA October 2013 10.1115/ICEF2013-19082
- Senecal , P. , Pomraning , E. , Richards , K. , and Som , S. An Investigation of Grid Convergence for Spray Simulations using an LES Turbulence Model SAE Technical Paper 2013-01-1083 2013 10.4271/2013-01-1083
- Lin , S. P. , and Reitz , R. D. Drop and Spray Formation from a Liquid Jet Annual Review of Fluid Mechanics 30 85 105 1998 10.1146/annurev.fluid.30.1.85
- Komada , K. , Sakaguchi , D. , Tajima , H. , Ueki , H. et al. Relation between Tip Penetration and Droplet Size of Diesel Spray SAE Technical Paper 2013-01-1599 2013 10.4271/2013-01-1599
- Genbao , L. , Jianming , C. , Minglong , L. , Yuhua , Q. et al. Experimental Study on the Size Distribution Characteristics of Spray Droplets of DME/diesel Blended Fuels Fuel Processing Technology 104 2012 352 355 10.1016/j.fuproc.2012.06.008
- Takeuchi , K. , Murayama , H. , Senda , J. , and Yamada , K. Droplet Size Distribution in Diesel Fuel Spray Bulletin of the JSME 26 215 May 1983 http://dx.doi.org/10.1299/jsme1958.26.797
- Senecal , P. , Richards , K. , Pomraning , E. , Yang , T. et al. A New Parallel Cut-Cell Cartesian CFD Code for Rapid Grid Generation Applied to In-Cylinder Diesel Engine Simulations SAE Technical Paper 2007-01-0159 2007 10.4271/2007-01-0159
- Richards , K. J. , Senecal , P. K. , and Pomraning , E. CONVERGE (Version 2.1.0) Convergent Science, Inc. Middleton, WI 2013
- Reitz , R. and Diwakar , R. Structure of High-Pressure Fuel Sprays SAE Technical Paper 870598 1987 10.4271/870598
- O'Rourke , P. and Amsden , A. The Tab Method for Numerical Calculation of Spray Droplet Breakup SAE Technical Paper 872089 1987 10.4271/872089
- Amsden , A. A. , O'Rourke , P. J. , and Butler , T. D. KIVA-II: A Computer Program for Chemically Reactive Flows with Sprays Los Alamos National Laboratory Report No. LA-11560-MS 1989
- Menon , S. , Yeung , P. , K. , and Kim , W. V. Effect of Subgrid Models on the Computed Interscale Energy Transfer in Isotropic Turbulence Computer and Fluids 25 2 165 1996 10.1016/0045-7930(95)00036-4
- Yoshizawa , A. , and Horiuti , K. A Statistically-Derived Subgrid-Scale Kinetic Energy Model for Large Eddy Simulation of Turbulent Flows Journal of the Physical Society of Japan 54 8 2834 1985 10.1063/1.863940
- Versteeg , H. K. , and Malalasekera , W. An Introduction to Computational Fluid Dynamics: The Finite Volume Method Second Pearson Education 2007 72 88 978-0131274983
- Pope , S. B. An Explanation of the Turbulent Round-Jet/Plane-Jet Anomaly AIAA Journal 16 3 279 81 March 1978 10.2514/3.7521
- Reitz , R. D. , and Bracco , F. V. Mechanisms of Breakup of Round Liquid Jets Encyclopedia of Fluid Mechanics, Gulf Pub. 233 Houston, TX, USA 1986
- Xin , J. , Ricart , L. , and Reitz , R. D. Computer Modeling of Diesel Spray Atomization and Combustion Combustion Science and Technology 137 1 6 171 194 10.1080/00102209808952050
- Schmidt , D. P. , and Rutland , C. J. A New Droplet Collision Algorithm Journal of Computational Physics 164 62 2000 10.1006/jcph.2000.6568
- Post , S. L. , and Abraham , J. Modeling the Outcome of Drop-Drop Collisions in Diesel Sprays Int. J. Multiphase Flow 28 997 2002 10.1016/S0301-9322(02)00007-1
- Faeth , G. M. Current Status of Droplet and Liquid Combustion Prog. Energy Combust. Sci 3 191 1977 10.1016/0360-1285(77)90012-0
- Senecal , P. K. , Pomraning , E. , Richards , K. J. , and Som , S. Grid Convergent Spray Models for Internal Combustion Engine CFD Simulations Proceedings of the ASME 2012 Internal Combustion Engine Division Fall Technical Conference, ICEF2012-92043 Vancouver, Canada 2012 10.1115/1.4024861
- Idicheria , C. and Pickett , L. Quantitative Mixing Measurements in a Vaporizing Diesel Spray by Rayleigh Imaging SAE Technical Paper 2007-01-0647 2007 10.4271/2007-01-0647
- 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
- Engine Combustion Network Spray Development and Vaporization http://www.sandia.gov/ecn/workshop/ECN2.php Jul. 2014
- Litzinger , T. , Dec , J.E. , and Santavicca , D. A. Planar Laser Rayleigh Scattering for Quantitative Vapor-Fuel Imaging in a Diesel Jet Combustion and Flame 109 65 1997 10.1016/S0010-2180(96)00126-5