Measurements of Soot Volume Fraction under Conditions Relevant to Engine Exhaust Using Four-Colour LII and Different Laser Energies Fengshan Liu 1 Xu He 0 Hongmei Li 0 Fushui Liu 0 Gregory J. Smallwood 1 LowFluence: SVFAnomaly High Fluence: Sublimation Beijing Institute of Technology , Beijing 100081 , China National Research Council , Building M-9, 1200 Montreal Road, Ottawa, ON. , Canada

] 100 Gravimetric=95 mg/m3 3/m 90 g [nm 80 o i ttra 70 n ceno 60 C too 50 S AcceptableRange: Mass=96.5+/-1.5mg/m3 Fluence=2.12+/-0.27mJ/mm2 Temperature=4120+/-90K 1064-nm Laser Fluence [mJ/mm2] Fig. 1 Variation of soot concentration and temperature with laser fluence.

 ModerateFluence -

1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00