Abstract
A simultaneous measurement system for measuring the concentration fluctuations of three species by the light absorption spectrometric method using laser diodes is developed in this study. Conventional methods utilize halogen lamps as a light source for concentration measurements, and multi-monochrometers are needed for these methods. Thus, conventional methods are expensive. By using laser diodes as the light source, multi-monochrometers can be omitted. A diffusion field consisting of three dye species in an axisymmetric turbulent jet was measured by the present concentration measurement system. To ascertain the validity of the 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 these systems can be used in various simultaneous measurements of concentration fluctuations of multiple species such as turbulent reactive flows.