The Experimental Investigations of Recirculated Exhaust Gas on Exhaust Emissions in a Diesel Engine


Abstract

The effects of recirculated exhaust gas on the characteristics of NOx and soot emissions under a wide range of engine loads were experimentally investigated by using a four-cycle, four-cylinder, sw irl chamber type, water-cooled diesel engine operating at three engine speeds. The purpose of this study was to develop the EGR-control system for reducing NOx and soot emissions simultaneously in diesel engines. The EGR system is used to reduce NOx emissions, and a novel diesel soot removal device with a cylinder-type scrubber for the experiment system was specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The experiments were performed at the fixed fuel injection timing of 4$^{\circ}$ ATDC regardless of experimental conditions. It was found that soot emissions in exhaust gases were reduced by 20 to 70% when the scrubber was applied in the range of the experimental conditions, and that NOx emissions decreased markedly, especially at higher loads, while soot emissions increased owing to the decrease in intake and exhaust oxygen concentrations, and the increase in equivalence ratio as the EGR rate is elevated.

Keywords

References

  1. Bae, M. W. and Kim, K. S., 1994, 'A Study on Soot Formation in Premixed Constant-Volume Propane Combustion (effect of Pressure, Temperature and Equivalemce Ratio),' KSME Journal, Vol. 8, No. 2, pp. 175-182
  2. Bae, M. W. and Lim, J., 1995, 'A Study on Effect of EGR upon Fuel Consumption Rate and NOX Emissions in Diesel Engines,' Transactions of the KSAE 953707, Vol. 3, No. 1, pp. 76-88
  3. Bae, M. W., 1999, 'A Study on the Effects of Recirculated Exhaust Gas on NOX and Soot Emissions in Diesel Engines with Scrubber EGR System,' SAE Paper No. 1999-01-3266, pp. 78-87
  4. Bae, M. W., Jeon, H. J. and Choi, J. S., 1999, 'The Effects of Recirculated Exhaust Gas on Fuel Economy and Exhaust Emissions in Marine Diesel Engines,' Proceeding of International Symposium on Internal Combustion Engine, pp. 91-105
  5. Daisho, Y., Uchida, N., Morita, K., Saito, T. and Shimogata, S., 1994, 'Effects of Supercharging and EGR on Diesel Combustion and Emissions,' International Symposium COMODIA 94, pp. 281-286
  6. Durnholtz, M., Eifler, G. and Endres, H., 1992, 'Exhaust-Gas Recirculation - A Measure to Reduce Exhaust Emissions of Diesel Engines,' SAE Paper No. 920725, pp. 151-158
  7. Girard, J. W., Gratz, L. D., Johnson, J. H., Bagley, S. T. and Leddy, D. G., 1999, 'A Study of the Character and Deposition Rate of Sulphur Specied in the EGR Cooling System of a Heavy Duty Diesel Engine,' SAE Paper No. 1999-01-3566, pp. 1-12
  8. Ikegami, M., 1996, 'Problems of Diesel Engine Combustion,' Combustion Science and Technology, Vol. 3, pp. 151-157
  9. Kamimoto, T., 1999, 'Automotive Engine of the Twenty-first Century,' Tokyo Institute of Technology Chronicle, No. 329, pp. 7-8 (in Japanese)
  10. Khan, I. M., Greeves, G. and Wang, C. H. T., 1973, 'Factors Affecting Smoke and Gaseous Emissions from Direct Injection Engines and a Method of Calculation,' SAE 730169, pp. 687-709
  11. Kobayashi, S., 1996, 'Approach Method to the Regulations of Automotive Diesel Engine Emissions,' Automotive Technology, Vol. 50, No. 1, pp. 71-77 (in Japanese)
  12. Kreso, A. M., Johnson, J. H., Gartz, L. D., Bagley, S. T. and Leddy, D. G., 1998, 'A Study of the Effectd of Exhaust Gas Recirculation on Heavy-Duty Diesel Engine Emissions,' SAE Paper No. 981422
  13. Ladommatos, N., Abdelhalim, S. M., Zhao, h. and Hu, Z, 1998, 'Effects of EGR on Heat Release in Diesel Combustion,' SAE Paper No. 980184
  14. Larsen, C., Levendis, Y. A., 1997, 'An Integrated Diesel Engine ART-EGR System for Pariculate/NOX Control Using Engine Sensory Inputs,' SAE Paper No. 970477
  15. Machacon, H. T. C., Shiga, S., Karasawa, T. and Nakamura, H., 1994, 'The Effects of EGR on Diesel Particulate Emissions,' International Symposium COMODIA 94, pp. 287-292
  16. Mayer, A. and Pauli, E., 1988, 'Emissions Concept for Vehicle Diesel Engine Supercharged with COMPREEX,' SAE 880008, pp. 77-89
  17. Nagai, T. and Kawakami, M., 1989, 'Reduction of NOX Emission in Medium-Speed Diesel Engines,' SAE Paper No. 891917, pp. 1-15
  18. Narusawa, K. and Odaka, M., 1990, 'An EGR Control Method for Heavy Duty Diesel Engines under Transient Operations,' SAE Paper No. 900444, pp. 1-14
  19. Odaka, M., 1989, 'EGR Application Method for Heavy-Duty Diesel Vehicles and its Effects under Actual Driving Conditions,' Internal Combustion Engine, Vol. 28, No. 362, pp. 17-23 (in Japanese)
  20. Psaras, D., Summers, J. C., Das, P. K., Ceynow, K., Khair, M. K. and DiSilverio, W., 1997, 'Achiving the 2004 Heavy-Duty Diesel Emissions Using Electronic EGR and a Cerium Based Fuel Borne Catalyst,' SAE Paper No. 970189, pp. 1-7
  21. Plee, S. L., Ahmad, T. and Myers, J. P., 1981, 'Flame Temperature Correlation for the Effects of Exhaust Gas Recirculation on Diesel Particulate and NOX Emissions,' SAE Paper No. 81195, pp. 75-91
  22. Satoh, K., Zhang, L., Hatanaka, H., Yokota, K. and Takatsuki, T., 1996, 'Relationship between NOX and SM Emission of D. I. Diesel Engine with EGR,' Proceedings of the 13th Internal Combustion Engine Symposium, pp. 447-452 (in Japanese)
  23. Shiozaki, T. and Suzuki, T., 1990, 'Effects of EGR on Engine Performance and Emission of a DI Diesel Engine,' Transactions of JSAE, No. 46, pp. 18-23 (in Japanese)
  24. Stumpp, G. and Banzhof, W., 1978, 'An Exhaust Gas Recirculation System for Diesel Engines,' SAE Paper No. 780222, pp. 1-12
  25. Uchida, N., Sugano, H., Daisho, Y. and Saito, T., 1993, 'Improvement of Diesel Engine Emission Characteristics by EGR and Turbocharger,' Transactions of JSAE, Vol. 24, No. 4, pp. 41-46
  26. Walder, C. J., 1973, 'Reduction of Emissions from Diesel Engines,' SAE Paper No. 730214, pp. 1-17