研究目的
To study an on-line measurement system to monitor the 2D distributions of temperature and H2O mole fraction on dynamic flames using tunable diode laser absorption tomography (TDLAT), including investigating the influence of beam distribution and grid number on reconstruction.
研究成果
The TDLAT sensor effectively reconstructs 2D temperature and H2O concentration distributions with a time resolution under 1 second. It shows good agreement with simulations and theoretical values, with relative errors less than 5.6% for temperature and 8.6% for concentration. The technique has potential for real-time combustion monitoring and feedback control, though improvements in scan frequency and algorithms are needed for higher resolutions.
研究不足
The method requires prior knowledge of combustion field symmetry and is limited by the finite number of laser beams, which restricts spatial resolution and makes dense meshing impossible. Errors can reach up to 10% due to air mixing and flow disturbances.
1：Experimental Design and Method Selection:
The study uses TDLAS combined with computed tomography (CT) for 2D reconstruction of temperature and H2O concentration. A modified adaptive algebraic reconstruction technique (MAART) is employed for iterative solving of linear equations derived from absorption spectroscopy.
2：Sample Selection and Data Sources:
Numerical simulations with four phantom flame distributions (one to four flames) and experimental setups with one and two flat flame burners using methane fuel at different equivalence ratios. Data sources include simulated line-of-sight integrations and experimental measurements from combustion fields.
3：List of Experimental Equipment and Materials:
DFB diode laser (1395 nm), wavelength meter (621B-IR), 1x16 fiber coupler, collimators, photodiodes, flat flame burner, flowmeters, B-type thermocouple, A/D acquisition card, and LabVIEW 2014 software.
4：Experimental Procedures and Operational Workflow:
Laser beams are arranged in 8x8 grids (16 beams total) with 4 cm spacing. The laser scans two H2O absorption lines, signals are detected by photodiodes, integrated absorbances are calculated using Lorentzian fitting, and MAART is applied for reconstruction with cubic spline interpolation for smoothing.
5：Data Analysis Methods:
Mean relative errors (eT and eC) are calculated to evaluate reconstruction accuracy. Statistical analysis includes comparisons with thermocouple measurements and theoretical values.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
