<title>Automotive exhaust gas analysis by infrared tunable diode laser absorption spectroscopy</title>

Abstract

Engine management optimisation and waste exhaust-gas control require engine transients measurements. The infrared tunable diode laser absorption spectroscopy (TDLAS) method can measure absolute molecule concentrations, gas temperature and pressure at high rate. The technique has been improved to measure NO or CO concentrations, as well as temperature and pressure of engine exhaust-gas. Measurements with a time resolution of one millisecond have been achieved in one ofthe cylinder exhaust pipe without any gas sampling.