Single-Shot 3D Flame Imaging Using CH-Based VLIF (Volumetric Laser Induced Fluorescence)

摘要

This work discusses the feasibility of single-shot VLIF (volumetric laser induced fluorescence) measurements in terms of signal level and reconstruction accuracy using both experimental and numerical methods. Experimentally, the excitation laser beam was expanded into a thick slab with a height of 50 mm and thickness of 10 mm to excite the CH radicals in the target flames. The volumetric LIF signals were then simultaneously captured by five intensified cameras, and the images were fed into a tomographic algorithm as inputs to obtain the 3D distribution of CH. The results show that single-shot 3D measurements with sufficient accuracy can be obtained in a volume of 9.3×9.3×32.7 mm3 with an excitation pulse energy of ～10 mJ. Numerically, models were developed to simulate the signal levels and reconstruction accuracies under different experimental conditions such as pulse energy. Good agreement was observed between the experimental and simulation results, motivating further efforts to explore the capabilities and limits of single-shot VLIF diagnostics using these models.