EFFECTS OF CAM PHASE AND SPARK RETARD TO INCREASE EXHAUST GAS TEMPERATURE IN THE COLD START PERIOD OF AN SI ENGINE

다국어 초록 (Multilingual Abstract)

The effects of spark timing and exhaust valve timing change on exhaust gas temperature during cold start period of an SI engine are studied through engine bench tests. The exhaust gas temperature increases when the spark timing or valve timing are retarded individually, due to late combustion or slow flame speed. Therefore, exhaust gas temperature shows a large increase when the two timings are retarded simultaneously. However, it is considered that combustion stability during cold start deteriorated under these retarded conditions. To increase exhaust gas temperature for fast warmup of catalysts while maintaining combustion stability, an optimal condition for spark and valve timing retard should be applied for the cold start period.

참고문헌 (Reference)

1 "valve timing operation modes on engine performances."

2 "temperature with UEGI technology during cold start."

3 "operation with retarded ignition"

4 "of intake timing effects on the cold start"

5 "flow visualization and numerical analysis of flow"

6 "distribution in a close-coupled catalytic converter."

7 "cyclic variations."

8 "behavior of a spark ignition engine. SAE Paper No."

9 "Trans. Korean Society of Automotive Engineering 9"

10 "SI engine operation" 1999

11 "SI engine" 1999

12 "SAE Paper No. 930386."

13 "Internal Combustion Engine" 1988

14 "Future gasoline diesel" 2000

15 "California LEV/ULEV standards"

16 ". Use of light-off catalysts to meet the" 1993

17 ". Effects of variable" 2001

18 ". Chang of catalyst" 2005