A multi-wavelength opacimeter for NOX and soot

A novel method to simultaneously determine the concentration of particles and NO₂, the main pollutants in the exhaust of diesel engines, is presented. It is based on multi-wavelength extinction measurement followed by a mathematical inversion algorithm. This paper gives an overview of the extinction measurement in general and extends the principle to a multi-wavelength measurement setup. The applicability of this new method is derived and validated with first experimental results as well as with simulations.