Cylindrical Bunsen

A novel ultraviolet Raman spectroscopic system based on vibrational Raman scattering effect is presented. Coupling of a time-resolved diagnostic and slow spectrometer scan is used for measurements of Raman scattering intensities of combustion species to derive relative concentration and temperature of the flame. Due to photon counting system high efficiency, relative lower energy of the incident light pulses, about 25 mJ, is required for the Raman scattering excitation. Low pulse energy application minimizes laser induced soot incandescence and vaporizations, which causing serious sample perturbations. Coupling of a time-resolved diagnostic and slow spectrometer scan allows decreasing width of the monochromator slit, which in turn increases the resolution of the system and minimizes of background radiation noise. The time resolved technique usage allows to minimize the noises in the detection system as well as the background radiation noise. The use of relative amplitude measurements technique minimizes the sensitivity of the system to fluctuations of the laser pulse energy. Temperature measurements are derived from the Raman Stokes/anti-Stokes intensities ratio. Relative concentrations of O2, CO, CO2, H2, water vapor and unburned fuel are obtained from the rati