This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Spray Characterization of a Single-Hole Gasoline Injector under Flash Boiling Conditions
ISSN: 0148-7191, e-ISSN: 2688-3627
Published November 11, 2014 by SAE International in United States
Annotation ability available
In the next future, improvements of direct injection systems for spark-ignited engines are necessary for the potential reductions in fuel consumptions and exhaust emissions. The admission and spread of the fuel in the combustion chamber is strictly related to the injector design and performances, such as to the fuel and environmental pressure and temperature conditions. In this paper the spray characterization of a GDI injector under normal and flash-boiling injection conditions has been investigated. The paper is mainly focused both on the capability of the injection apparatus/temperatures controller system to realize flash-boiling conditions, and the diagnostic setup to catch the peculiarities of the spray behavior. The work aims reporting the spray characterization under normal and flash-boiling conditions. Flash-boiling is a phenomenon that occurs in certain engine conditions when the in-cylinder pressure is lower than the saturation pressure of the fuel, and leads to internal boiling and vapor bubbles creation near the nozzle exit.
A customized sensing of the injector nose permitted the temperature control of the nozzle up to 360 K while a remote-controlled thermostatic device allowed the fuel heating from ambient to 393 K. An axially-disposed, 0.200 mm in diameter, single-hole injector was used with l/d ratio equal to 1 and static flow@100 bar: 2.45 g/s, using commercial gasoline. A 1.0 ms duration single pulse strategy was adopted at the injection pressure of 10.0 MPa. The spray evolved in a quiescent optically-accessible vessel pressurize at 0.05, and 0.1 MPa at ambient temperature of the gas (N2).
Images of the sprays were acquired by Mie-scattering technique using a C-Mos cycle-resolved high speed camera as detector, an off-line processing of the captured images gave tip penetrations and cone-angles vs. time from the start of injection. At flash-boiling conditions clear increasing of the spray-cone angle were observed with respect to the normal one producing consequences on the distribution of the fuel in the combustion vessel.
CitationAllocca, L., Montanaro, A., Di Gioia, R., and Bonandrini, G., "Spray Characterization of a Single-Hole Gasoline Injector under Flash Boiling Conditions," SAE Technical Paper 2014-32-0041, 2014, https://doi.org/10.4271/2014-32-0041.
- Zhao , F. , Lai , M.C. , Harrington , D.L. Automotive Spark-Ignition Direct-Injection Gasoline Engines Prog. Energy Combust. Sci. 1999 25 437 562
- Stach , T. , Schlerfer , J. , and Vorbach , M. New Generation Multi-hole Fuel Injector for Direct-Injection SI Engines - Optimization of Spray Characteristics by Means of Adapted Injector Layout and Multiple Injection SAE Technical Paper 2007-01-1404 2007 10.4271/2007-01-1404
- Serras-Pereira , J. , Aleiferis , P. , Richardson , D. , and Wallace , S. Spray Development, Flow Interactions and Wall Impingement in a Direct-Injection Spark-Ignition Engine SAE Technical Paper 2007-01-2712 2007 10.4271/2007-01-2712
- Oza , R. and Sinnamon , J. An Experimental and Analytical Study of Flash-Boiling Fuel Injection SAE Technical Paper 830590 1983 10.4271/830590
- Park , B.S. , Lee , S.Y. An Experimental Investigation of the Flash Atomization Mechanism Atomization and Sprays 4 1994 159 179
- Yildiz , D. et al A Study on the Dynamic of a Flashing Jet Final Contract Research Report EAR0030/2002 Von Karman Institute for Fluid Dynamics 2002
- Reitz , R.D. A Photographic Study of Flash-Boiling Atomization Aerosol Science and Technology 12 1990 561 569
- Arora , R. , Morgan , C.J. , Naber , J.D. , Lee , S.Y. Flash Boiling Spray Characterization of a Gasoline Multi-hole Injector in a Heated Pressure Vessel ILASS Americas 2011 paper #162, 23 rd Annual Conference on Liquid Atomization and Spray Systems Ventura May 15 18
- Zeng , W. , Xu , M. , Zhang , G. , Zhang , Y. , Cleary , D.J. Atomization and Vaporization for Flash-Boiling Multi-Hole Sprays with Alcohol Fuels Fuel 95 2012 287 297
- Zigan , L. , Schmitz , I. , Flugel , A. , Wensing , M. , Leipertz , A. Structure of Evaporating Single- and Multicomponent Fuel Sprays for 2 nd Generation Gasoline Direct Injection Fuel 90 2011 348 363
- Negro , S. , Bianchi , G.M. Superheated Fuel Injection Modeling: An Engineering Approach International Journal of Thermal Sciences 50 2011 1460 1471
- Bosch , W. The Fuel Rate Indicator: A New Measuring Instrument For Display of the Characteristics of Individual Injection SAE Technical Paper 660749 1966 10.4271/660749
- Wallace , I. Injection Rate Gauge: Pass Off Information and User Instructions Fuel & Engine Management Systems Graz December 2002
- Allocca , L. , Alfuso , S. , Corcione , F. E. Assessment of Dynamic Performances of Diesel Solenoid Injectors for a Multiple Injection Common Rail System SAE Technical Paper 2003-01-21
- Malaguti S. , Fontanesi S. , Cantore G. , Allocca L. , Montanaro A. Modelling of Primary Breakup of a Gasoline Direct Engine Multi-Hole Spray Atomization and Sprays 23 10 861 888
- Alfuso , S. , Allocca , L. , Caputo , G. , Corcione , F. et al. Experimental Investigation of a Spray from a Multi-jet Common Rail Injection System for Small Engines SAE Technical Paper 2005-24-090 2005 10.4271/2005-24-090
- Sher , E. , Bar Kohany , T. , Rashkovan , A. Flash Boiling Atomization Prog. Energy Combust. Sci 2008 24 417 39
- Lee , J. , Madablushi , R. , Fotache , S. , Gopalakrishnan , S. , Schmidt , D.P. Flash Flow of Superheated Jet Fuel P. Combust. Inst. 2009 32 3215 22