THIESEL 2020.Thermo-and Fluid Dynamic Processes in Direct Injection Engines.8th-11th September

'The THIESEL 2020 Conference on Thermo-and Fluid Dynamic Processes in Direct Injection Engines planned in Valencia (Spain) for 8th to 11th September 2020 has been successfully held in a virtual format, due to the COVID19 pandemic. In spite of the very tough environmental demands, combustion engines will probably remain the main propulsion system in transport for the next 20 to 50 years, at least for as long as alternative solutions cannot provide the flexibility expected by customers of the 21st century. But it needs to adapt to the new times, and so research in combustion engines is nowadays mostly focused on the new challenges posed by hybridization and downsizing. The topics presented in the papers of the conference include traditional ones, such as Injection & Sprays, Combustion, but also Alternative Fuels, as well as papers dedicated specifically to CO2 Reduction and Emissions Abatement.Papers stem from the Academic Research sector as well as from the IndustryXandra Marcelle, M.; Desantes Fernández, JM. (2020). THIESEL 2020.Thermo-and Fluid Dynamic Processes in Direct Injection Engines.8th-11th September. Editorial Universitat Politècnica de València. http://hdl.handle.net/10251/150759EDITORIA

A new method to predict high and low-temperature ignition delays under transient thermodynamic conditions and its experimental validation using a Rapid Compression-Expansion Machine

A new procedure to predict both high-temperature stage and cool flames ignition delays under transient thermodynamic conditions has been developed in this paper. The results obtained have been compared with those obtained from the Livengood & Wu integral method, as well as with other predictive methods and with direct chemical kinetic simulations and experimental data. All simulations have been performed with CHEMKIN, employing a detailed chemical kinetic mechanism. The simulations and predictions have been validated in the working range versus experimental results obtained from a Rapid CompressionExpansion Machine (RCEM). The study has been carried out with n-heptane and iso-octane, as diesel and gasoline fuel surrogates, under a wide range of initial temperatures (from 358 K to 458 K), initial pressures (0.14 MPa and 0.17 MPa), compression ratios (15 and 17), EGR rates (from 0% to 50%) and equivalence ratios (from 0.3 to 0.8). The experimental results show good agreement with the direct chemical kinetic simulations and with the new predictive method proposed. In fact, the mean relative deviation between experiments and simulations is equal to 1.719% for n-heptane and equal to 1.504% for iso-octane. Besides, the new method has shown good predictive capability not only for the hightemperature stage of the process but also for cool flames, being the mean relative deviation versus the experimental data lower than 2.900%. Better predictions of the ignition delay have been obtained with the new procedure than the ones obtained with the classic Livengood & Wu expression, especially in those cases showing a two-stage ignition pattern.The authors would like to thank different members of the CMT-Motores Termicos team of the Universitat Politecnica de Valencia for their contribution to this work. The authors would also like to thank the director of LAV-ETH, Konstantinos Boulouchos, for the Dario Lopez-Pintor's internship at LAV. Finally, the authors would like to thank the Spanish Ministry of Education for financing the PhD. Studies of Dario Lopez-Pintor (grant FPU13/02329).Desantes Fernández, JM.; Bermúdez, V.; López, JJ.; López Pintor, D. (2016). A new method to predict high and low-temperature ignition delays under transient thermodynamic conditions and its experimental validation using a Rapid Compression-Expansion Machine. Energy Conversion and Management. 123:512-522. https://doi.org/10.1016/j.enconman.2016.06.051S51252212

Experimental validation of an alternative method to predict high and low-temperature ignition delays under transient thermodynamic conditions for PRF mixtures using a Rapid Compression-Expansion Machine

An alternative procedure to predict both high-temperature stage and cool flames ignition delays under transient thermodynamic conditions is intended to be validated in this paper. An experimental study has been carried out in a Rapid Compression-Expansion Machine (RCEM), using different iso-octane/nheptane blends in order to cover a wide range of octane numbers (from 25 to 75) under a wide range of initial temperatures (from 363 K to 423 K), compression ratios (14 and 19), O2 molar rates (from 21% to 16%) and equivalence ratios (from 0.4 to 0.8). The results obtained have been used to validate direct chemical kinetic simulations, as well as to evaluate the alternative predictive method and the Livengood & Wu integral method. Simulations have been performed solving a detailed chemical kinetic mechanism in CHEMKIN. The experimental results show good agreement with the chemical kinetic simulations and with the alternative predictive method. In fact, the mean relative deviation between experiments and simulations is equal to 1.7%, 2.2% and 3.1% for PRF25, PRF50 and PRF75, respectively. Besides, the alternative method has shown good predictive capability not only for the high-temperature stage of the process, but also for cool flames, being the mean relative deviation versus the experimental data lower than 3.3% for all fuels. Better predictions of the ignition delay have been obtained with the alternative procedure than the ones obtained with the classic Livengood & Wu expression, especially in those cases showing a two-stage ignition pattern, in which the Livengood & Wu integral method is not able to predict the high-temperature stage of the process.The authors would like to thank different members of the CMT-Motores Termicos team of the Universitat Politecnica de Valencia for their contribution to this work. The authors would also like to thank the Spanish Ministry of Education for financing the PhD. Studies of Dario Lopez-Pintor (Grant FPU13/02329). This work was partly funded by the Spanish Ministry of Economy and Competitiveness, project TRA2015-67136-R.Desantes Fernández, JM.; Bermúdez, V.; López, JJ.; López Pintor, D. (2016). Experimental validation of an alternative method to predict high and low-temperature ignition delays under transient thermodynamic conditions for PRF mixtures using a Rapid Compression-Expansion Machine. Energy Conversion and Management. 129:23-33. https://doi.org/10.1016/j.enconman.2016.09.089S233312

Characterization and prediction of the discharge coefficient of non-cavitating diesel injection nozzles

An experimental and theoretical study about the characterization of the discharge coefficient of diesel injection nozzles under non-cavitating conditions is presented in this paper. A theoretical development based on the boundary layer equations has been performed to define the discharge coefficient of a convergent nozzle. The discharge coefficient has been experimentally obtained for a standard diesel fuel under a wide range of Reynolds numbers by two different techniques: mass flow rate measurements and permeability measurements. Five different nozzles have been used: two multi-hole nozzles that have been tested in the frame of this work, and three other single-hole nozzles, the data of which have been taken from previous studies. The experimental results show good agreement with the theoretical expressions, proving that it is possible to predict the discharge coefficient of a non-cavitating nozzle with the equations shown in this paper.The authors would like to thank different members of the CMT-Motores Termicos team of the Universitat Politecnica de Valencia for their contribution to this work, specially to R. Payri, F.J. Salvador, J. Gimeno and G. Bracho. This work was partly sponsored by "Ministerio de Economia y Competitividad" in the frame of the project "Comprension de la influencia de combustibles no convencionales en el proceso de inyeccion y combustion tipo diesel", reference TRA2012-36932. The equipment used in this work has been partially supported by FEDER project funds "Dotacion de infraestructuras cientifico tecnicas para el Centro Integral de Mejora Energetica y Medioambiental de Sistemas de Transporte (CiMeT), (FEDER-ICTS-2012-06)", in the frame of the operation program of unique scientific and technical infrastructure of the Ministry of Science and Innovation of Spain. This support is gratefully acknowledged by the authors. Finally, the authors would like to thank the Spanish Ministry of Education for financing the PhD. studies of Dario Lopez-Pintor (grant FPU13/02329).Desantes Fernández, JM.; López, JJ.; Carreres Talens, M.; López-Pintor, D. (2016). Characterization and prediction of the discharge coefficient of non-cavitating diesel injection nozzles. Fuel. 184:371-381. https://doi.org/10.1016/j.fuel.2016.07.02637138118

A numerical study of the effect of nozzle diameter on diesel combustion ignition and flame stabilization

This is the author's version of a work that was accepted for publication in International Journal of Engine Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published as https://doi.org/10.1177/1468087419864203.[EN] The role of nozzle diameter on diesel combustion is studied by performing computational fluid dynamics calculations of Spray A and Spray D from the Engine Combustion Network. These are well-characterized single-hole sprays in a quiescent environment chamber with thermodynamic conditions representative of modern diesel engines. First, the inert spray evolution is described with the inclusion of the concept of mixing trajectories and local residence time into the analysis. Such concepts enable the quantification of the mixing rate, showing that it decreases with the increase in nozzle diameter. In a second step, the reacting spray evolution is studied focusing on the local heat release rate distribution during the auto-ignition sequence and the quasi-steady state. The capability of a well-mixed-based and a flamelet-based combustion model to predict diesel combustion is also assessed. On one hand, results show that turbulence-chemistry interaction has a profound effect on the description of the reacting spray evolution. On the other hand, the mixing rate, characterized in terms of the local residence time, drives the main changes introduced by the increase of the nozzle diameter when comparing Spray A and Spray D.The author(s) disclosed receipt of the following financial support for the research, authorship and/or publication of this article: The work was partially funded by the Government of Spain through the CHEST Project (TRA2017-89139-C2-1-R) and by Universitat Politecnica de Valencia through the Programa de Ayudas de Investigaciony Desarrollo (PAID-01-16).Desantes Fernández, JM.; García-Oliver, JM.; Novella Rosa, R.; Pachano-Prieto, LM. (2020). A numerical study of the effect of nozzle diameter on diesel combustion ignition and flame stabilization. International Journal of Engine Research. 21(1):101-121. https://doi.org/10.1177/1468087419864203S101121211Pickett, L. M., & Siebers, D. L. (2002). An investigation of diesel soot formation processes using micro-orifices. Proceedings of the Combustion Institute, 29(1), 655-662. doi:10.1016/s1540-7489(02)80084-0Pickett, L. M., & Siebers, D. L. (2005). Orifice Diameter Effects on Diesel Fuel Jet Flame Structure. Journal of Engineering for Gas Turbines and Power, 127(1), 187-196. doi:10.1115/1.1760525Du, C., Andersson, S., & Andersson, M. (2018). Two-dimensional measurements of soot in a turbulent diffusion diesel flame: the effects of injection pressure, nozzle orifice diameter, and gas density. Combustion Science and Technology, 190(9), 1659-1688. doi:10.1080/00102202.2018.1461850Ishibashi, R., & Tsuru, D. (2016). An optical investigation of combustion process of a direct high-pressure injection of natural gas. Journal of Marine Science and Technology, 22(3), 447-458. doi:10.1007/s00773-016-0422-xPang, K. M., Jangi, M., Bai, X.-S., Schramm, J., & Walther, J. H. (2017). Effects of Nozzle Diameter on Diesel Spray Flames: A numerical study using an Eulerian Stochastic Field Method. Energy Procedia, 142, 1028-1033. doi:10.1016/j.egypro.2017.12.350Pickett, L. M., Manin, J., Genzale, C. L., Siebers, D. L., Musculus, M. P. B., & Idicheria, C. A. (2011). Relationship Between Diesel Fuel Spray Vapor Penetration/Dispersion and Local Fuel Mixture Fraction. SAE International Journal of Engines, 4(1), 764-799. doi:10.4271/2011-01-0686García-Oliver, J. M., Malbec, L.-M., Toda, H. B., & Bruneaux, G. (2017). A study on the interaction between local flow and flame structure for mixing-controlled Diesel sprays. Combustion and Flame, 179, 157-171. doi:10.1016/j.combustflame.2017.01.023Dahms, R. N., Paczko, G. A., Skeen, S. A., & Pickett, L. M. (2017). Understanding the ignition mechanism of high-pressure spray flames. Proceedings of the Combustion Institute, 36(2), 2615-2623. doi:10.1016/j.proci.2016.08.023Gimeno, J., Martí-Aldaraví, P., Carreres, M., & Peraza, J. E. (2018). Effect of the nozzle holder on injected fuel temperature for experimental test rigs and its influence on diesel sprays. International Journal of Engine Research, 19(3), 374-389. doi:10.1177/1468087417751531Matusik, K. E., Duke, D. J., Kastengren, A. L., Sovis, N., Swantek, A. B., & Powell, C. F. (2017). High-resolution X-ray tomography of Engine Combustion Network diesel injectors. International Journal of Engine Research, 19(9), 963-976. doi:10.1177/1468087417736985Pandurangi, S. S., Bolla, M., Wright, Y. M., Boulouchos, K., Skeen, S. A., Manin, J., & Pickett, L. M. (2016). Onset and progression of soot in high-pressure n-dodecane sprays under diesel engine conditions. International Journal of Engine Research, 18(5-6), 436-452. doi:10.1177/1468087416661041Aubagnac-Karkar, D., Michel, J.-B., Colin, O., & Darabiha, N. (2017). Combustion and soot modelling of a high-pressure and high-temperature Dodecane spray. International Journal of Engine Research, 19(4), 434-448. doi:10.1177/1468087417714351Ihme, M., Ma, P. C., & Bravo, L. (2018). Large eddy simulations of diesel-fuel injection and auto-ignition at transcritical conditions. International Journal of Engine Research, 20(1), 58-68. doi:10.1177/1468087418819546Yue, Z., & Reitz, R. D. (2017). An equilibrium phase spray model for high-pressure fuel injection and engine combustion simulations. International Journal of Engine Research, 20(2), 203-215. doi:10.1177/1468087417744144Bhattacharjee, S., & Haworth, D. C. (2013). Simulations of transient n-heptane and n-dodecane spray flames under engine-relevant conditions using a transported PDF method. Combustion and Flame, 160(10), 2083-2102. doi:10.1016/j.combustflame.2013.05.003Pei, Y., Hawkes, E. R., & Kook, S. (2013). Transported probability density function modelling of the vapour phase of an n-heptane jet at diesel engine conditions. Proceedings of the Combustion Institute, 34(2), 3039-3047. doi:10.1016/j.proci.2012.07.033Pang, K. M., Jangi, M., Bai, X.-S., Schramm, J., & Walther, J. H. (2018). Modelling of diesel spray flames under engine-like conditions using an accelerated Eulerian Stochastic Field method. Combustion and Flame, 193, 363-383. doi:10.1016/j.combustflame.2018.03.030D’Errico, G., Lucchini, T., Contino, F., Jangi, M., & Bai, X.-S. (2014). Comparison of well-mixed and multiple representative interactive flamelet approaches for diesel spray combustion modelling. Combustion Theory and Modelling, 18(1), 65-88. doi:10.1080/13647830.2013.860238Kösters, A., Karlsson, A., Oevermann, M., D’Errico, G., & Lucchini, T. (2015). RANS predictions of turbulent diffusion flames: comparison of a reactor and a flamelet combustion model to the well stirred approach. Combustion Theory and Modelling, 19(1), 81-106. doi:10.1080/13647830.2014.982342Lucchini, T., D’Errico, G., Onorati, A., Frassoldati, A., Stagni, A., & Hardy, G. (2017). Modeling Non-Premixed Combustion Using Tabulated Kinetics and Different Fame Structure Assumptions. SAE International Journal of Engines, 10(2), 593-607. doi:10.4271/2017-01-0556Pal, P., Keum, S., & Im, H. G. (2015). Assessment of flamelet versus multi-zone combustion modeling approaches for stratified-charge compression ignition engines. International Journal of Engine Research, 17(3), 280-290. doi:10.1177/1468087415571006Pope, S. B. (1978). An explanation of the turbulent round-jet/plane-jet anomaly. AIAA Journal, 16(3), 279-281. doi:10.2514/3.7521Novella, R., García, A., Pastor, J. M., & Domenech, V. (2011). The role of detailed chemical kinetics on CFD diesel spray ignition and combustion modelling. Mathematical and Computer Modelling, 54(7-8), 1706-1719. doi:10.1016/j.mcm.2010.12.048CONVERGE manual. Madison, WI: Convergent Science, 2016.Yao, T., Pei, Y., Zhong, B.-J., Som, S., Lu, T., & Luo, K. H. (2017). A compact skeletal mechanism for n-dodecane with optimized semi-global low-temperature chemistry for diesel engine simulations. Fuel, 191, 339-349. doi:10.1016/j.fuel.2016.11.083Perez E. Application of a flamelet-based combustion model to diesel-like reacting sprays. Unpublished PhD Thesis, Universitat Politècnica de València, Valencia, 2019.Peters, N. (2000). Turbulent Combustion. doi:10.1017/cbo9780511612701Naud, B., Novella, R., Pastor, J. M., & Winklinger, J. F. (2015). RANS modelling of a lifted H2/N2 flame using an unsteady flamelet progress variable approach with presumed PDF. Combustion and Flame, 162(4), 893-906. doi:10.1016/j.combustflame.2014.09.014Payri, R., García-Oliver, J. M., Xuan, T., & Bardi, M. (2015). A study on diesel spray tip penetration and radial expansion under reacting conditions. Applied Thermal Engineering, 90, 619-629. doi:10.1016/j.applthermaleng.2015.07.042Narayanaswamy, K., Pepiot, P., & Pitsch, H. (2014). A chemical mechanism for low to high temperature oxidation of n-dodecane as a component of transportation fuel surrogates. Combustion and Flame, 161(4), 866-884. doi:10.1016/j.combustflame.2013.10.012Kahila, H., Wehrfritz, A., Kaario, O., Ghaderi Masouleh, M., Maes, N., Somers, B., & Vuorinen, V. (2018). Large-eddy simulation on the influence of injection pressure in reacting Spray A. Combustion and Flame, 191, 142-159. doi:10.1016/j.combustflame.2018.01.004Pang, K. M., Jangi, M., Bai, X.-S., Schramm, J., Walther, J. H., & Glarborg, P. (2019). Effects of ambient pressure on ignition and flame characteristics in diesel spray combustion. Fuel, 237, 676-685. doi:10.1016/j.fuel.2018.10.020Tagliante, F., Poinsot, T., Pickett, L. M., Pepiot, P., Malbec, L.-M., Bruneaux, G., & Angelberger, C. (2019). A conceptual model of the flame stabilization mechanisms for a lifted Diesel-type flame based on direct numerical simulation and experiments. Combustion and Flame, 201, 65-77. doi:10.1016/j.combustflame.2018.12.00

Effects of intake pressure on particle size and number emissions from premixed diesel low-temperature combustion

In this study, 10 premixed diesel low-temperature combustion engine operating conditions were chosen based on engine intake pressure (1.2-1.6 bar), intake oxygen concentration (10%, 11%, and 12%), and injection timing (-24 degrees after top dead centre in all test conditions). At each intake oxygen concentration, the effects of intake pressure on combustion parameters and emission measurements (carbon monoxide, hydrocarbons, nitrogen oxides, particulate matter mass concentration, and particle size distributions) were analyzed. Although increased intake pressure resulted in higher in-cylinder charge air density that improved fuel/air premixing and late-cycle oxidation quality, higher intake pressure also advanced the start of combustion and thereby decreased the time available for fuel and air premixing. But even with the decrease in premixing time available before start of combustion, increased intake pressure caused significant decreases in carbon monoxide, hydrocarbon, particulate matter mass, and particle number emissions. Particle size distribution measurements allowed greater understanding of how higher intake pressure decreased the particulate matter mass concentrations with respect to particle size. To further investigate the experimental results, a zero-dimensional engine heat release code was used to analyze combustion temperatures, and a one-dimensional free spray model was used to estimate the relative levels of liquid fuel spray impingement on the piston surface and maximum local equivalence ratio at start of combustion for each test case. Therefore, though the premixing time was shortened by higher intake pressures, the decreased emissions were understood by combined effects of enhanced fuel and air premixing quality and improved late-cycle oxidation near the end of combustion.This research has been carried out in the frame of the project PROMETEO/2010/032 supported by the Generalitat Valenciana. Financial support for Christopher P. Kolodziej was provided by the Spanish Ministry of Education (Formacion del Profesorado Universitario).Desantes Fernández, JM.; Benajes Calvo, JV.; García Oliver, JM.; Kolodziej, CP. (2014). Effects of intake pressure on particle size and number emissions from premixed diesel low-temperature combustion. International Journal of Engine Research. 15(2):222-235. https://doi.org/10.1177/1468087412469514S22223515

Experimental Characterization of the Thermodynamic Properties of Diesel Fuels Over a Wide Range of Pressures and Temperatures

The influence of pressure and temperature on some of the important thermodynamic properties of diesel fuels has been assessed for a set of fuels. The study focuses on the experimental determination of the speed of sound, density and compressibility (via the bulk modulus) of these fuels by means of a method that is thoroughly described in this paper. The setup makes use of a common-rail injection system in order to transmit a pressure wave through a high-pressure line and measure the time it takes for the wave to travel a given distance. Measurements have been performed in a wide range of pressures (from atmospheric pressure up to 200 MPa) and temperatures (from 303 to 353 K), in order to generate a fuel properties database for modelers on the field of injection systems for diesel engines to incorporate to their simulations.This work was partly sponsored by "Ministerio de Economia y Competitividad" (Spanish Ministry of Economy) in the frame of the project "Comprension de la influencia de combustibles no convencionales en el proceso de inyeccion y combustion tipo diesel", reference TRA2012-36932. The equipment used in this work hasDesantes Fernández, JM.; Salvador Rubio, FJ.; Carreres Talens, M.; Jaramillo-Císcar, D. (2015). Experimental Characterization of the Thermodynamic Properties of Diesel Fuels Over a Wide Range of Pressures and Temperatures. SAE International Journal of Fuel and Lubricants. 8(1):190-199. https://doi.org/10.4271/2015-01-0951S1901998

The role of the in-cylinder gas temperature and oxygen concentration over low load reactivity controlled compression ignition combustion efficiency

Several studies carried out with the aim of improving the RCCI (reactivity controlled compression ignition) concept in terms of thermal efficiency conclude that the main cause of the reduced efficiency at light loads is the reduced combustion efficiency. The present study used both a 3D computational model and engine experiments to explore the effect of the oxygen concentration and intake temperature on RCCI combustion efficiency at light load. The experiments were conducted using a single-cylinder heavy-duty research diesel engine adapted for dual fuel operation. Results suggest that it is possible to achieve an improvement of around 1.5% in the combustion efficiency with both strategies studied; the combined effect of intake temperature and in-cylinder fuel blending as well as the combined effect of oxygen concentration and in-cylinder fuel blending (ICFB). In addition, the direct comparison of both strategies suggests that the combustion losses trend is mainly associated to the in-cylinder equivalence ratio stratification, which is determined by the diesel to gasoline ratio in the blend since the injection timing is kept constant for all the tests. Moreover, the combined effect of the intake temperature and ICFB promotes a slight improvement in the combustion losses over the combined effect of the oxygen concentration and ICFB. (C) 2014 Elsevier Ltd. All rights reserved.The authors gratefully acknowledge the modeling support and guidance of Jose Manuel Pastor and VOLVO Group Trucks Technology (CN-2012-46) for supporting this research.Desantes Fernández, JM.; Benajes Calvo, JV.; García Martínez, A.; Monsalve Serrano, J. (2014). The role of the in-cylinder gas temperature and oxygen concentration over low load reactivity controlled compression ignition combustion efficiency. Energy. 78:854-868. https://doi.org/10.1016/j.energy.2014.10.080S8548687

Large-eddy simulation analysis of the influence of the needle lift on the cavitation in diesel injector nozzles

The cavitation phenomenon has a strong influence on the internal flow and spray development in diesel injector nozzles. Despite its importance, there are many aspects which still remain unclear, especially for partial needle lifts when the injector is in the opening and closing phases. For that reason, the current paper is focused on the influence of the needle lift on the internal flow in a diesel nozzle. This study was carried out with three-dimensional simulations at a high injection pressure (160 MPa) using a homogeneous equilibrium model implemented in OpenFOAM to model the cavitation phenomenon. The nozzle was simulated with large-eddy simulation methods at six different needle lifts (10 mm, 30 mm, 50 mm, 75 mm, 100 mm and 250 mm), providing relevant information about the evolution of the internal flow, the turbulence development (the vorticity, the turbulence–cavitation interaction and the turbulent structures) and the flow characteristics in the nozzle outlet (the mass flow, the momentum flux and the effective velocity) with the needle position.Desantes Fernández, JM.; Salvador Rubio, FJ.; Carreres Talens, M.; Martínez López, J. (2015). Large-eddy simulation analysis of the influence of the needle lift on the cavitation in diesel injector nozzles. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering. 229(4):407-423. doi:10.1177/0954407014542627S4074232294Faeth, G. ., Hsiang, L.-P., & Wu, P.-K. (1995). Structure and breakup properties of sprays. International Journal of Multiphase Flow, 21, 99-127. doi:10.1016/0301-9322(95)00059-7Park, S. H., Suh, H. K., & Lee, C. S. (2009). Effect of Bioethanol−Biodiesel Blending Ratio on Fuel Spray Behavior and Atomization Characteristics. Energy & Fuels, 23(8), 4092-4098. doi:10.1021/ef900068aPAYRI, R., GARCIA, J., SALVADOR, F., & GIMENO, J. (2005). Using spray momentum flux measurements to understand the influence of diesel nozzle geometry on spray characteristics. Fuel, 84(5), 551-561. doi:10.1016/j.fuel.2004.10.009Suh, H. K., & Lee, C. S. (2008). Effect of cavitation in nozzle orifice on the diesel fuel atomization characteristics. International Journal of Heat and Fluid Flow, 29(4), 1001-1009. doi:10.1016/j.ijheatfluidflow.2008.03.014Payri, R., Salvador, F. J., Gimeno, J., & de la Morena, J. (2009). Effects of nozzle geometry on direct injection diesel engine combustion process. Applied Thermal Engineering, 29(10), 2051-2060. doi:10.1016/j.applthermaleng.2008.10.009Park, S. H., Kim, S. H., & Lee, C. S. (2009). Mixing Stability and Spray Behavior Characteristics of Diesel−Ethanol−Methyl Ester Blended Fuels in a Common-Rail Diesel Injection System. Energy & Fuels, 23(10), 5228-5235. doi:10.1021/ef9004847Desantes, J. M., Payri, R., Salvador, F. J., & Gil, A. (2006). Development and validation of a theoretical model for diesel spray penetration. Fuel, 85(7-8), 910-917. doi:10.1016/j.fuel.2005.10.023Desantes, J. M., Payri, R., Garcia, J. M., & Salvador, F. J. (2007). A contribution to the understanding of isothermal diesel spray dynamics. Fuel, 86(7-8), 1093-1101. doi:10.1016/j.fuel.2006.10.011Badock, C., Wirth, R., Fath, A., & Leipertz, A. (1999). Investigation of cavitation in real size diesel injection nozzles. International Journal of Heat and Fluid Flow, 20(5), 538-544. doi:10.1016/s0142-727x(99)00043-0Som, S., Aggarwal, S. K., El-Hannouny, E. M., & Longman, D. E. (2010). Investigation of Nozzle Flow and Cavitation Characteristics in a Diesel Injector. Journal of Engineering for Gas Turbines and Power, 132(4). doi:10.1115/1.3203146Macian, V., Payri, R., Margot, X., & Salvador, F. J. (2003). A CFD ANALYSIS OF THE INFLUENCE OF DIESEL NOZZLE GEOMETRY ON THE INCEPTION OF CAVITATION. Atomization and Sprays, 13(5-6), 579-604. doi:10.1615/atomizspr.v13.i56.80Alajbegovic, A., Meister, G., Greif, D., & Basara, B. (2002). Three phase cavitating flows in high-pressure swirl injectors. Experimental Thermal and Fluid Science, 26(6-7), 677-681. doi:10.1016/s0894-1777(02)00179-6Unverdi, S. O., & Tryggvason, G. (1992). A front-tracking method for viscous, incompressible, multi-fluid flows. Journal of Computational Physics, 100(1), 25-37. doi:10.1016/0021-9991(92)90307-kBrackbill, J. ., Kothe, D. ., & Zemach, C. (1992). A continuum method for modeling surface tension. Journal of Computational Physics, 100(2), 335-354. doi:10.1016/0021-9991(92)90240-yPlesset M, Devine R. Effect of exposure time on cavitation damage. Report (Office of Naval Research Contract Nonr-220(28)), California Institute of Technology, Pasadena, California, USA, 1965.Chen, Y., & Heister, S. D. (1996). MODELING CAVITATING FLOWS IN DIESEL INJECTORS. Atomization and Sprays, 6(6), 709-726. doi:10.1615/atomizspr.v6.i6.50Vortmann, C., Schnerr, G. H., & Seelecke, S. (2003). Thermodynamic modeling and simulation of cavitating nozzle flow. International Journal of Heat and Fluid Flow, 24(5), 774-783. doi:10.1016/s0142-727x(03)00003-1Echouchene, F., Belmabrouk, H., Le Penven, L., & Buffat, M. (2011). Numerical simulation of wall roughness effects in cavitating flow. International Journal of Heat and Fluid Flow, 32(5), 1068-1075. doi:10.1016/j.ijheatfluidflow.2011.05.010Salvador, F. J., Romero, J.-V., Roselló, M.-D., & Martínez-López, J. (2010). Validation of a code for modeling cavitation phenomena in Diesel injector nozzles. Mathematical and Computer Modelling, 52(7-8), 1123-1132. doi:10.1016/j.mcm.2010.02.027Salvador, F. J., Hoyas, S., Novella, R., & Martínez-López, J. (2011). Numerical simulation and extended validation of two-phase compressible flow in diesel injector nozzles. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 225(4), 545-563. doi:10.1177/09544070jauto1569Payri, F., Payri, R., Salvador, F. J., & Martínez-López, J. (2012). A contribution to the understanding of cavitation effects in Diesel injector nozzles through a combined experimental and computational investigation. Computers & Fluids, 58, 88-101. doi:10.1016/j.compfluid.2012.01.005Salvador, F. J., Martínez-López, J., Caballer, M., & De Alfonso, C. (2013). Study of the influence of the needle lift on the internal flow and cavitation phenomenon in diesel injector nozzles by CFD using RANS methods. Energy Conversion and Management, 66, 246-256. doi:10.1016/j.enconman.2012.10.011Salvador, F. J., Martínez-López, J., Romero, J.-V., & Roselló, M.-D. (2013). Computational study of the cavitation phenomenon and its interaction with the turbulence developed in diesel injector nozzles by Large Eddy Simulation (LES). Mathematical and Computer Modelling, 57(7-8), 1656-1662. doi:10.1016/j.mcm.2011.10.050Piomelli, U. (1999). Large-eddy simulation: achievements and challenges. Progress in Aerospace Sciences, 35(4), 335-362. doi:10.1016/s0376-0421(98)00014-1Launder, B. E., & Spalding, D. B. (1974). The numerical computation of turbulent flows. Computer Methods in Applied Mechanics and Engineering, 3(2), 269-289. doi:10.1016/0045-7825(74)90029-2Payri, F., Bermúdez, V., Payri, R., & Salvador, F. J. (2004). The influence of cavitation on the internal flow and the spray characteristics in diesel injection nozzles. Fuel, 83(4-5), 419-431. doi:10.1016/j.fuel.2003.09.010Payri, R., Salvador, F. J., Gimeno, J., & de la Morena, J. (2009). Study of cavitation phenomena based on a technique for visualizing bubbles in a liquid pressurized chamber. International Journal of Heat and Fluid Flow, 30(4), 768-777. doi:10.1016/j.ijheatfluidflow.2009.03.011Martínez López, J. (s. f.). Estudio computacional de la influencia del levantamiento de aguja sobre el flujo interno y el fenómeno de la cavitación en toberas de inyección diésel. doi:10.4995/thesis/10251/29291Tabor, G. R., & Baba-Ahmadi, M. H. (2010). Inlet conditions for large eddy simulation: A review. Computers & Fluids, 39(4), 553-567. doi:10.1016/j.compfluid.2009.10.007Payri, R., Gimeno, J., Marti-Aldaravi, P., & Bracho, G. (2013). Study of the influence of the inlet boundary conditions in a LES simulation of internal flow in a diesel injector. Mathematical and Computer Modelling, 57(7-8), 1709-1715. doi:10.1016/j.mcm.2011.11.019de Villiers E. The potential of large eddy simulation for the modeling of wall bounded flows. PhD Thesis, Imperial College of Science, Technology and Medicine, London, UK, 2006.Lee, J. W., Min, K. D., Kang, K. Y., Bae, C. S., Giannadakis, E., Gavaises, M., & Arcoumanis, C. (2006). Effect of piezo-driven and solenoid-driven needle opening of common-rail diesel injectors on internal nozzle flow and spray development. International Journal of Engine Research, 7(6), 489-502. doi:10.1243/14680874jer00806Desantes, J. M., Payri, R., Salvador, F. J., & De la Morena, J. (2010). Influence of cavitation phenomenon on primary break-up and spray behavior at stationary conditions. Fuel, 89(10), 3033-3041. doi:10.1016/j.fuel.2010.06.004Lesieur, M., Métais, O., & Comte, P. (2005). Large-Eddy Simulations of Turbulence. doi:10.1017/cbo9780511755507Sagaut, P. (2001). Large Eddy Simulation for Incompressible Flows. Scientific Computation. doi:10.1007/978-3-662-04416-

A recent eulerian langrarian CFD methodology for modeling direct injection diesel sprays

[EN] The global objective of this work is to show the capabilities of the Eulerian Lagrangian spray atomization (ELSA) model for the simulation of Diesel sprays in cold starting con- ditions. Our main topic is to focus in the analysis of spray formation and its evolution ◦at low temperature 255 K (−18 C) and nonevaporative conditions. Spray behavior and several macroscopic properties, included the liquid spray penetration, and cone angle are also characterized. This study has been carried out using different ambient temper- ature and chamber pressure conditions. Additionally, the variations of several technical quantities, as the area coefficient and effective diameter are also studied. The results are compared with the latest experimental results in this field obtained in our institute. In the meantime, we also compare with the normal ambient temperature at 298 K (25◦ C) where the numerical validation of the model has shown a good agreement.In this article, KAD did all the simulations, analyze the results coming from them, and wrote the first version of the manuscript under the direct supervision of SH. JMD, AG and FR gave continuous advice during the work and collaborated in the final form of the manuscript. This work was supported in part by the Spanish Government in the frame of the Project `Metodos LES para la simulacion de chorros multifasicos, Ref. ENE2010-18542 and by Renault. Dung Khuong-Anh has been supported in part by the VECOM (Vehicle Concept Modeling), EU FP7 Marie Curie Initial Training Network (ITN) Grant Agreement 213543 and in conjunction with Renault SA, France.Desantes Fernández, JM.; Hoyas Calvo, S.; Gil Megías, A.; Khuong, AD.; Ravet, F. (2014). A recent eulerian langrarian CFD methodology for modeling direct injection diesel sprays. International Journal of Computational Methods. 11(3):1343012-1343029. https://doi.org/10.1142/S0219876213430123S1343012134302911