around the spark plug, the combustion quality could be improved
by a moderate reduction of the injected fuel mass.
3.2.2. Effect of the start position on the combustion characteristics
Fig. 9 shows the combustion characteristics of the
first-combustion cylinder with different start positions. The start
position determined the total amount of fresh air in the
first-combustion cylinder, but the air volume in the cylinder during
the compression stroke should be slightly less than during the
power stroke to ensure the reliability of a direct start. The