کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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736042 | 893705 | 2006 | 15 صفحه PDF | دانلود رایگان |
This work investigates the use of laser-induced gas breakdown for simultaneously igniting and measuring fuel-to-air ratio of CH4–air and H2–air combustible mixtures. The fuel-to-air ratio is determined using the measured spectral peak ratio Io,Hα/Io,OIIo,Hα/Io,OI. Sparks are produced using a single-mode, Q-switched Nd–YAG laser. The laser produces a beam of 6 mm in diameter at the wavelength of 1064 nm and pulse duration of 5.5 ns. The beam optics is designed to have mainly a beam splitter and a focusing lens. The beam splitter is coated to reflect the laser beam and transmit emission lines with wavelengths from 600 to 900 nm which are then collected by a fiberoptic cable and detected by an imaging spectrometer–detector assembly. The results showed a linear dependence of the spectral peak ratio on the equivalence ratio that can be generally expressed by φ=a(Io,Hα/Io,OI)+bφ=a(Io,Hα/Io,OI)+b, where a and b are the parameters that depend on the gas pressure. Using the least-square curve fitting technique to fit the experimental data, a calibration curve for calculating the equivalence ratio as a function of the ratio of (Io,Hα/Io,OI)(Io,Hα/Io,OI) was generated.
Journal: Optics and Lasers in Engineering - Volume 44, Issue 6, June 2006, Pages 520–534