The progress in mixing on macro- and microscale is visualized by means of optical measurement systems. The Particle Image Velocimetry (PIV) is used to measure the velocity field inside the mixing system. The source term of the local energy dissipation is calculated by the information of the gradients of velocity. The Laser Induced Fluorescence (LIF) Technique is further developed for the simultaneous application of two different colors. A mixture of an inert and a reacting fluorescent dye is injected into a vessel. The macromixing is reflected by the inert dye serving as a tracer. Mixing on molecular scale is required for the progress of chemical reactions. Therefore the reacting dye indirectly visualizes the micromixing by changing its fluorescent characteristics during the reaction. The concentration fields of the two dyes are determined from measured fluorescence intensities. Based on these the local degree of deviation is calculated for detecting the areas of micromixing. Measurements are performed in a mixing system equipped with two glass cylinders. The working fluid is a mixture of glycerol and some adittional chemicals. The experiments are conducted in the laminar region. The injected dyes are stretched and folded in the flow field of the mixing system creating lamellar structures. The two optical measurement systems are prepared for the analysis of interrelation of macro- and micromixing subject to the local dissipation of energy.

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