A PARAMETRIC SENSITIVITY STUDY OF GDI SPRAY CHARACTERISTICS USING A 3-D TRANSIENT MODEL

  • Comer, M.A. (Division of Mechanical Engineering, Cardiff University) ;
  • Bowen, P.J. (Division of Mechanical Engineering, Cardiff University) ;
  • Sapsford, S.M. (Ricardo Consulting Engineers Ltd.) ;
  • Kwon, S.I. (Doowon Technical College)
  • Published : 2004.09.01

Abstract

Potential fuel economy improvements and environmental legislation have renewed interest in Gasoline Direct Injection (GDI) engines. Computational models of fuel injection and mixing processes pre-ignition are being developed for engine optimisation. These highly transient thermofluid models require verification against temporally and spatially resolved data-sets. The authors have previously established the capability of PDA to provide suitable temporally and spatially resolved spray characteristics such as mean droplet size, velocity components and qualitative mass distribution. This paper utilises this data-set to assess the predictive capability of a numerical model for GDI spray prediction. After a brief description of the two-phase model and discretisation sensitivity, the influence of initial spray conditions is discussed. A minimum of 5 initial global spray characteristics are required to model the downstream spray characteristics adequately under isothermal, atmospheric conditions. Verification of predicted transient spray characteristics such as the hollow-cone, cone collapse, head vortex, stratification and penetration are discussed, and further improvements to modelling GDI sprays proposed.

Keywords

References

  1. Chinn, J. J. and Yule, A. J. (1997). Computational analysis of swirl atomizer internal flow. Proc. ICLASS 97, Seoul, Korea, 868-875
  2. Comer, M. A., Bowen, P. J., Sapsford, S. M., Bates, C. J. and Johns, R. J. R. (1999). Transient 3D analysis of a DI gasoline injector spray. Journal of Atomisation and Sprays 9, 467-482 https://doi.org/10.1615/AtomizSpr.v9.i5.20
  3. Han, Z. and Reitz, R. D. (1997). Internal structure of vaporising pressure-swirl fuel sprays. Proc. ICLASS 97, Seoul, Korea, 474-48
  4. Harada, J., Tomita, T., Mizuno, H., Mashiki, Z. and Ito, Y (1997). Development of direct injection gasoline engine. SAE Paper No. 970540
  5. Hoffman, J. A., Khatri, E, Martin, J. K. and Coates, S. W. (1998). Mass-related properties of atomizers for directinjection SI engines. SAE Paper No. 98050
  6. Iwamoto, Y, Noma, K., Nakayama, O., Yamauchi, T. and Ando, H. (1997). Development of gasoline direct injection engine. SAE Paper No. 970541
  7. Kume, T., Iwamoto, Y, Iida, K., Murakami, M., Akishino, K. and Ando, H. (1998). Combustion control technologies for direct injection SI engine. SAE Paper No. 960600
  8. Liu, A. B., Mather, D. and Reitz, R. D. (1993). Modelling the effects of drop drag and breakup on fuel sprays. SAE Paper No. 930072
  9. Lui, Z., Lin Y, Arai M., Obakata T. and Reitz R. D. (1997). Numerical study of liquid spray characteristics. Proc. ICLASS 97, Seoul, Korea, 804-811
  10. Ohsuga, M., Shiraishi, T., Nogi, T., Nakayama, Y. and Sukegawa, Y. (1997). Mixture preparation for directinjection SI engines. SAE Paper No. 970542
  11. Parrish, S. E. and Farrell, P. V. (1997). Transient spray characteristics of a direct-injection spark-ignited fuel injector. SAE Paper No. 970629
  12. Reitz, R. D. and Diwakar, R. (1986). Effect of breakup on fuel sprays. SAE Paper No. 860469
  13. Ricardo Software. (2001) VECTIS Computational fluid dynamics users manual. Version 3.5. Ricardo. London
  14. Stanglmaier, R. H., Hall, M. J. and Matthews, R. D. (1998). Fuel-spray/Charge motion interaction within the cylinder of a direct-injected, 4-valve, SI engine. SAE Paper No. 980155
  15. Shelby, M. H., VanDerWege, B. A. and Hochgreb, S. (1998). Early spray development in gasoline directinjected spark ignition engines. SAE Paper No. 980160
  16. Wigley, G., Hargrave, G. K. and Heath, J. (1998). A High power, high resolution LDA/PDA system applied to dense gasoline direct injection sprays. Proc. 9th Int. Symp. on Applications. of Laser Techniques to Fluid Mechanics Lisbon, 9.4.1 9.4.7