2022 年 7 巻 p. 21-26
In this study, we developed a simultaneous measurement system for measuring the concentration fluctuations of three species by the light absorption spectrometric method using pulsed laser diodes. The conventional method utilizes halogen lamps or continuous laser diodes as light sources for concentration measurements. These light sources require multi-monochromators or dichroic mirrors, which makes these methods rather expensive. However, pulsed laser diodes as the light sources eliminate the need for additional multi-monochromators and dichroic mirrors. A diffusion field consisting of three dye species in an axisymmetric turbulent jet was measured using the developed concentration measurement system. To ascertain the validity of our concentration measurements, we compared the present measurement results with those of a single dye species and previous studies. It was observed that the concentrations of the three dye species were measured accurately by the present measuring system. Therefore, such low-cost concentration measurement systems can be developed and applied in various simultaneous measurements of concentration fluctuations of multiple species such as in turbulent reactive flows.
