Investigation of natural convection in cubical enclosure using laser induced fluorescence

Temperature measurements are extremely important and they are used in many technical and engineering processes, including the analysis of natural convection. In contrast to the commonly used thermocouples and Pt100 temperature sensors, which allow point temperature measurements, laser induced fluorescence technique (LIF) allows the imaging of temperature fields throughout the area. An obvious disadvantage of thermocouples and Pt100 sensors is the possibility that the probes can affect  the fluid flow, changing its structure. This problem does not appear in LIF measurements and better accuracy of temperature mapping is obtained. This work focuses on describing one-color LIF technique (using one fluorescent dye) in theoretical and practical terms. The experimental set-up is described, as well as  a number of operations required to get the temperature field of the whole domain. The results of the natural convection process analysis in the configuration of one side wall heated and the opposite one cooled, with the use of laser induced fluorescence technique are presented.

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