Skip to main content
Log in

Fuel injection rate and its variation of a GDI injector operated in engine motoring conditions

  • Original Article
  • Published:
Journal of Mechanical Science and Technology Aims and scope Submit manuscript

Abstract

The cylinder head assembly from a GDI engine was separated to build a GDI fuel injection system capable of controlling the rail pressure and fuel injection levels. The GDI fuel injection system is driven by a three-phase AC motor with a direct connection between the camshaft and the motor. The operating conditions of the GDI fuel injection system are equivalent to those of actual engine driving. The AC motor drives the GDI high-pressure fuel pump by rotating the engine camshaft. In the GDI high-pressure fuel pump (HPFP), fuel is pressurized on the upward stroke of the plunger and pumped to the fuel rail. Fuel rail pressure (FRP) control is possible by controlling the opening/closing timing of the HPFP’s pressure control valve (PCV), the fuel injection duration and the camshaft speed. In order to calculate the fuel injection rate characteristics of the GDI injector statistically under fixed conditions of the camshaft speed, FRP, and injection duration, the measurements of the fuel injection rate were repeated at regular time intervals. To calculate the variation of the fuel injection rate, the S/N (signal-to-noise) ratio, which is the average FRP divided by the FRP standard deviation, was calculated. A fuel injection rate was obtained under 88 experimental conditions combining the three conditions of the HPFP’s PCV opening/closing timing, fuel injection duration, and camshaft rotational speed. The smaller S/N ratio shows the larger FRP variation. Also, it was identified that the S/N ratio is related to the variation of the fuel injection rate.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. A. A. Reddy and J. M. Mallikarjuna, Parametric study on a gasoline direct injection engine — A CFD analysis, SAE Paper 2017-26-0039 (2017).

  2. F. Q. Zhao and M. C. Lai, A review of mixture preparation and combustion control strategies for spark-ignited direct-injection gasoline engines, SAE Paper 970627 (1997).

  3. R. Golzari, Y. Li and H. Zhao, Impact of port fuel injection and in-cylinder fuel injection strategies on gasoline engine emissions and fuel economy, SAE Paper 2016-01-2174 (2016).

  4. J. G. Spakowski, J. Kazour, B. C. Kaswer, M. Harstad and T. D. Spegar, GDI high efficiency fuel pump for fast engine starts and reduced cam loads, SAE Paper No. 2019-01-1196 (2019).

  5. Robert Bosch GmbH, Diesel Engine Management, 4th Ed., Bentley Publishers (2005).

  6. F. Q. Zhao, M. C. Lai and D. L. Harrington, Automotive spark-ignited direct-injection gasoline engines, Progress in Energy and Combustion Science, 25 (2016) 437–562.

    Article  Google Scholar 

  7. E. A. Rivera, N. Mastro, J. Zizelman, J. Kirwan and R. Ooyama, Development of injector for the direct injection homogeneous market using design for six sigma, SAE Paper 2010-01-0594 (2016).

  8. M. Cavanagh, R. Pellini and S. J. Pinson, Advances in gasoline direct injection fuel pump technologies, SAE Paper 2018-01-0367 (2018).

  9. H. Zhao, Advanced Direct Injection Combustion Engine Technologies and Development, Cambridge: Woodhead Publishing Limited (2010).

    Book  Google Scholar 

  10. C. Wang, H. Xu, J. M. Herreros, J. Wang and R. Cracknell, Impact of fuel and injection system on particle emissions from a GDI engine, Applied Energy, 132 (2014) 178–91.

    Article  Google Scholar 

  11. R. Payri, G. Bracho, J. Gimeno and A. Bautista, Rate of injection modelling for gasoline direct injectors, Energy Conversion and Management, 166 (15) (2018) 424–432.

    Article  Google Scholar 

  12. H. Husted, T. D. Spegar and J. Spakowski, The effects of GDI fuel pressure on fuel economy, SAE Paper 2014-01-1438 (2014).

  13. Q. Liu, H. Chen, Y. Hu, P. Sun and J. Li, Modeling and control of the fuel injection system for rail pressure regulation in GDI engine, IEEE/ASME Transactions on Mechatronics, 19 (5) (2014) 1501–1513.

    Article  Google Scholar 

  14. T. D. Spegar, S. I. Chang, S. Das, E. Norkin and R. Lucas, An analytical and experimental study of a high pressure single piston pump for gasoline direct injection (GDI) engine applications, SAE Paper 2009-01-1504 (2009).

  15. T. D. Spegar, Minimizing gasoline direct injection (GDI) fuel system pressure pulsations by robust fuel rail design, SAE Paper 2011-01-1225 (2011).

  16. K. Hiraku, K. Tokuo and H. Yamada, Development of high pressure fuel pump by using hydraulic simulator, SAE Paper 2005-01-0099 (2005).

  17. J. M. Lee and C. H. Lee, A development of fuel rail pressure control system for evaluating GDI injector performance, KSAE Spring Conference, 18KSAE-B003 (2018).

  18. B. J. Lee and C. H. Lee, Fuel rail pressure control characteristics of a GDI high pressure fuel pump using a newly developed experimental system controlled with a microcontroller, International Journal of Automotive Technology, 22 (2) 489–497 (2021).

    Article  Google Scholar 

  19. Surface Vehicle Recommended Practice: Low Pressure Gasoline Fuel Injector, J1832, SAE International (2016).

  20. Surface Vehicle Recommended Practice: Direct Injection Gasoline Fuel Injector Characterization, J2713, SAE International (2018).

Download references

Acknowledgments

This study was supported by the Research Program funded by the Seoul National University of Science and Technology.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Choong Hoon Lee.

Additional information

Lee, Byoung-Jin received his B.S. (2019) in Department of Automotive Engineering at Seoul National University of Science and Technology. His research interests are flow measurements and control of fuel injection system in automotive. He has worked in Samsung Electronics Co. Ltd since 2020.

Lee, Choong-Hoon received his B.S. (1985), M.S. (1987), and Ph.D. degrees (1996) in Mechanical Engineering from Seoul National University. He worked as a diesel engine development engineer for Daewoo Heavy Industry for six years. He was a visiting research fellow at the Engine Research Center at the University of Wisconsin-Madison in 1997. He has worked in the Department of Automotive Engineering at Seoul National University of Technology as a Professor since 2000. His research interests are the measurement and control of sprays and flows.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Lee, B.J., Lee, C.H. Fuel injection rate and its variation of a GDI injector operated in engine motoring conditions. J Mech Sci Technol 35, 5741–5751 (2021). https://doi.org/10.1007/s12206-021-1143-6

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12206-021-1143-6

Keywords

Navigation