A Tunable Diode-laser Absorption Spectroscopy (TDLAS)Thermometry for Combustion Diagnostics

摘要

A sensor based on tunable diode laser absorption spectroscopy (TDLAS) was constructed for non-intrusive temperature and water vapor concentration measurement. Absorption lines were selected and analysed using spectrum database Hitran2004. Two fiber-coupled near infrared distributed feedback (DFB) lasers was used to probe two water vapor absorption features (7168.437 cm~(-1) and 7185.597 cm~(-1)) near 1393nm which has high sensitivity of temperature measurement in 500-1300K. Successful experiments were performed in a CH_4/Air premixed flat flame burner using direct absorption wavelength scanned method at a 1KHz scan rate. Comparison with thermocouple measurements, the maxium error of the method is less than 80K (6.7%).