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Study of Near Nozzle Spray Characteristics of Ethanol under Different Saturation Ratios
ISSN: 0148-7191, e-ISSN: 2688-3627
Published October 17, 2016 by SAE International in United States
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Atomization of fuel sprays is a key factor in controlling the combustion quality in the direct-injection engines. In this present work, the effect of saturation ratio (Rs) on the near nozzle spray patterns of ethanol was investigated using an ultra-high speed imaging technique. The Rs range covered both flash-boiling and non-flash boiling regions. Ethanol was injected from a single-hole injector into an optically accessible constant volume chamber at a fixed injection pressure of 40 MPa with different fuel temperatures and back pressures. High-speed imaging was performed using an ultrahigh speed camera (1 million fps) coupled with a long-distance microscope. Under non-flash boiling conditions, the effect of Rs on fuel development was small but observable. Clear fuel collision can be observed at Rs=1.5 and 1.0. Under the flash boiling conditions, near-nozzle spray patterns were significant different from the non-flash boiling ones. Reducing Rs from 1.0 to 0.2 would lead to clear radial expansion in both the initial and quasi-steady stages due to the bubble formation and explosion. However, the micro cone angle was smaller when further reducing Rs to 0.1 as the nozzle flow developed into the hydraulic flipping regime.
CitationWang, B., Badawy, T., Li, Y., Xu, H. et al., "Study of Near Nozzle Spray Characteristics of Ethanol under Different Saturation Ratios," SAE Technical Paper 2016-01-2189, 2016, https://doi.org/10.4271/2016-01-2189.
- Heywood JB. Internal Combustion Engine Fundamentals. vol. 21. 1988.
- Schmitz, I., Ipp, W., and Leipertz, A., "Flash Boiling Effects on the Development of Gasoline Direct-Injection Engine Sprays," SAE Technical Paper 2002-01-2661, 2002, doi:10.4271/2002-01-2661.
- Motjabi M. Optical Analysis of Multi-Stream GDI Sprays under Various Engine Operating Conditions by. PhD thesis, Loughborough University, 2011.
- Zeng W, Xu M, Zhang G, Zhang Y, Cleary DJ. Atomization and vaporization for flash-boiling multi-hole sprays with alcohol fuels. Fuel 2012;95:287-97.
- Crua C, Heikal MR, Gold MR. Microscopic imaging of the initial stage of diesel spray formation. Fuel 2015;157:140-50.
- Badock C, Wirth R, Fath A, Leipertz A. Investigation of cavitation in real size diesel injection nozzles. Int J Heat Fluid Flow 1999;20:538-44.
- Moon S, Tsujimura T, Gao Y, Park S, Wang J, Kurimoto N, et al. Biodiesel effects on transient needle motion and near-exit flow characteristics of a high-pressure diesel injector. Int J Engine Res 2013;15:504-18.
- Serras-Pereira J, Van Romunde Z, Aleiferis PG, Richardson D, Wallace S, Cracknell RF. Cavitation, primary break-up and flash boiling of gasoline, iso-octane and n-pentane with a real-size optical direct-injection nozzle. Fuel 2010;89:2592-607.
- Demirbas A. Progress and recent trends in biofuels. Prog Energy Combust Sci 2007;33:1-18.
- Aleiferis PG, Van Romunde ZR. An analysis of spray development with iso-octane, n-pentane, gasoline, ethanol and n-butanol from a multi-hole injector under hot fuel conditions. Fuel 2013;105:143-68.
- Chan QN, Bao Y, Kook S. Effects of injection pressure on the structural transformation of flash-boiling sprays of gasoline and ethanol in a spark-ignition direct-injection (SIDI) engine. Fuel 2014;130:228-40.
- Hoffmann, G., Befrui, B., Berndorfer, A., Piock, W. et al., "Fuel System Pressure Increase for Enhanced Performance of GDi Multi-Hole Injection Systems," SAE Int. J. Engines 7(1):519-527, 2014, doi:10.4271/2014-01-1209.
- Manin J, Bardi M, Pickett LM, Payri R. Boundary condition and fuel composition effects on injection processes of diesel sprays at the microscopic level. Int J Multiph Flow 2013:1-4.
- Pickett, L., Manin, J., Kastengren, A., and Powell, C., "Comparison of Near-Field Structure and Growth of a Diesel Spray Using Light-Based Optical Microscopy and X-Ray Radiography," SAE Int. J. Engines 7(2):1044-1053, 2014, doi:10.4271/2014-01-1412.
- Crua, C., Shoba, T., Heikal, M., Gold, M. et al., "High-Speed Microscopic Imaging of the Initial Stage of Diesel Spray Formation and Primary Breakup," SAE Technical Paper 2010-01-2247, 2010, doi:10.4271/2010-01-2247.
- Stetsyuk V, Crua C, Pearson R, Gold M. Direct imaging of primary atomisation in the near-nozzle region of diesel sprays. ILASS Eur 26th Annu Conf Liq At Spray Syst 2014:8-10.
- Manin J, Kastengren A, Payri R. Understanding the Acoustic Oscillations Observed in the Injection Rate of a Common-Rail Direct Injection Diesel Injector. J Eng Gas Turbines Power 2012;134:122801.
- Naber, J. and Siebers, D., "Effects of Gas Density and Vaporization on Penetration and Dispersion of Diesel Sprays," SAE Technical Paper 960034, 1996, doi:10.4271/960034.
- Hiroyasu, H. and Arai, M., "Structures of Fuel Sprays in Diesel Engines," SAE Technical Paper 900475, 1990, doi:10.4271/900475.
- Xue Q, Som S, Battistoni M, Longman DE, Zhao H, Senecal PK, et al. Three-dimensional Simulations of the Transient Internal Flow in a Diesel Injector: Effects of Needle Movement. ILASS Am 2013.
- Suh HK, Lee CS. Effect of cavitation in nozzle orifice on the diesel fuel atomization characteristics. Int J Heat Fluid Flow 2008;29:1001-9.
- Sou A, Hosokawa S, Tomiyama A. Effects of cavitation in a nozzle on liquid jet atomization. Int J Heat Mass Transf 2007;50:3575-82.