3.3.4 Influence of number of sprays on BFO combustion (case C and F)
It is a well-known fact that the smaller the fuel injection hole diameter is the higher is the excess air ratio in the spray at the same spray penetration length [4].
In case F, the injection hole diameter is 0.19mm compared to 0.23mm in case C. In order to keep the injection hole area constant, the number of injection holes is increased from 8 to 12.
Compared to case C, in case F at 8｡?TDC less soot is formed at each point of impingement. However, at 26｡?TDC stripe shaped clouds of soot are visible (similar to case E). Even though swirl is not applied in case F, neighboring flames easily overlap because the number of sprays is too high.
