Simultaneous detection of Nox and particulate in exhaust of a CR Diesel engine by UV-visible spectroscopy

Non-intrusive diagnostic techniques based on broadband (190-550 nm) extinction and scattering spectroscopy were applied to undiluted exhaust Common-Rail (CR) diesel engine. The influence of engine speed and load on soot mass concentration, size distribution of emitted particles and NOx concentration was analyzed. NOx concentration was evaluated by ""in situ"" ultraviolet-visible absorption measurements and compared with those obtained by conventional analyzer. The extinction and scattering spectra were compared with those evaluated by the Lorenz-Mie model for spherical particles in order to retrieve the size, the number concentration of the emitted particles and particulate mass.