A Study on Time-Resolved Laser Induced Incandescence Analysis Method for the Measurement of Primary Particle Size in Diesel Exhaust

A simple correlation between particle size and the time-resolved laser induced incandescence signal is introduced and applied to a diesel engine for the measurement of primary particle size in the raw exhaust gas. The measurements from time-resolved LII signal are calibrated for all experimental conditions using Transmission Electron Microscope photographs to investigate the differences between particle size from TEM photographs and that estimated by LII. An evaluation of uncertainty in the LII measurements is also presented. From the comparison between the two measurements and uncertainty analysis, it can be concluded that the time-resolved LII theory employed in this study can be used as a useful tool for measuring primary particle size in engine exhaust since the measurements from LII are reliable and in a good agreement with those from TEM imaging. From a practical point of view, the strategy for particle size measurements presented here are simple and straightforward in its application.