International Journal of Automotive Technology

The Korean Society of Automotive Engineers (한국자동차공학회)
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NUMERICAL ANALYSIS OF FUEL INJECTION IN INTAKE MANIFOLD AND INTAKE PROCESS OF A MPI NATURAL GAS ENGINE

  • XU B. Y. (Department of Mechanical and Electronic Engineering, Shandong Institute of Architecture and Engineering) ;
  • LIANG F. Y. (Graduate School of Science and Technology, Chiba University) ;
  • CAI S. L. (School of Mechanical Engineering, Jinan University) ;
  • QI Y. L. (Department of Mechanical and Electronic Engineering, Shandong Institute of Architecture and Engineering)
  • Published : 2005.12.01
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Abstract

Unsteady state free natural gas jets injected from several types of injectors were numerically simulated. Simulations showed good agreements with the schlieren experimental results. Moreover, injections of natural gas in intake manifolds of a single-valve engine and a double-valve engine were predicted as well. Predictions revealed that large volumetric injections of natural gas in intake manifolds led to strong impingement of natural gas with the intake valves, which as a result, gave rise to pronounced backward reflection of natural gas towards the inlets of intake manifolds, together with significant increase in pressure in intake manifold. Based on our simulations, we speculated that for engines with short intake manifolds, reflections of the mixture of natural gas and air were likely to approach the inlets of intake manifolds and subsequently be inbreathed into other cylinders, resulting in non-uniform mixture distributions between the cylinders. For engines with long intake manifolds, inasmuch as the degrees of intake interferences between the cylinders were not identical in light of the ignition sequences, non-uniform intake charge distributions between the cylinders would occur.

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References

  1. Brault, J. M., Maymir, D. S., Samimy, M., Matsuki and M. (1998). An investigation of mixture formation processes during start -up of a natural gas powered SI engine. SAE Papers No. 981387
  2. Deng, Z. W. and Zeng, Q. Q. (1998). A Primary Discussion on Developing Natural Gas Vehicles. Natural Gas Industry 18, 2, 56-58
  3. Hao, L. J., Zhang, F. J. and Huang, Y. (2000). Present situation and future trends of natural gas fuelled engine. Automotive Engineering 22, 5, 332-337
  4. Hosch, J. W. and Walters, J. P. (1977). High spatial resolution schlieren photography. Applied Optics 16, 2, 473-485 https://doi.org/10.1364/AO.16.000473
  5. Japan Gas Association. (1996). Research Results of Natural Gas Vehicle Application. Japan Gas Association Press House. Tokyo
  6. Kim, S. E. and Choudhury, D. (1995). A near-wall treatment using wall functions sensitized to pressure gradient. ASME Separated and Complex Flows, 217, 273-280
  7. Lee, S. Y., Huh, K. Y., Kim, M. and Lee, J. H. (2001). Analysis of in-cylinder fuel-air mixture distribution in a heavy duty CNG engine. Int. J. Automotive Technology 2, 3, 93-101
  8. Liang, F. Y. and Xu, B. Y. (2003). Numerical simulation of intake process for longitudinal straight inlet port multi-point injection (MPI) natural gas engine. J. Shanghai Jiaotong University 37,9, 1402-1406
  9. Matsuki, M., Nanoka, K., Amemiya, T., Tanabe, Y., Shimizu, D. and Ohmura, I. (1996). Development of a lean bum engine with a variable valve timing mechanism. SAE Papers No. 960583
  10. Matsuura, H., Ishibashi, K., Fujii, I. and Kajitani, I. (1995). Combustion process ofCNG engine with MPI system. Final Manuscripts of JSAE Annual Symp. 233-236
  11. Nakamura, Y. and Muranaka, S. (1999). Gasoline Engine For Automobile (Revised edn.). Sankaido, Tokyo
  12. Partaker, S. V. (1981). Numerical Heat Transfer and Fluid Flow. Hemisphere Public Corporation. New York
  13. Shih, T. H., Liou, W. W. and Shabbir, A. (1995). A new k-$\alpha$ eddy-viscosity model for high reynolds number turbulent flows-model development and validation. Computer Fluids 24, 3, 227-238 https://doi.org/10.1016/0045-7930(94)00032-T
  14. Yang, M. L. (2001). Automobile and Environment Protection. China Logistics Publishing House. Beijing
  15. Zhang, H. W. (2002). Opportunities and strategies about development and application of automobile with gasfuel. J. Highwayand Transportation Research and Development 19, 5, 131-135