Modeling and visualization of thermohydraulic processes under the influence of external dynamic forces

The article deals with the relevant issue related to accounting for the impact of external dynamic forces on thermal-hydraulic processes. These include processes of natural circulation, mixing of the coolant in the equipment of nuclear power plants, steam separation processes, operating modes of heating systems for high-viscosity media, operation of absorption refrigeration devices installed on small and large sea vessels. The principal approach to researching this problem is the experimental method which makes it possible to comprehensively consider these processes on small-scale models. For this, an experimental stand of an original design was developed. The parameters obtained during the operation were visualized and converted into graphic images, which were analyzed using the open-source computer vision library OpenCV. A new method for visualization of mixing processes of non-isothermal flows is proposed, the implementation of which resulted in the integral and local characteristics of this process. It is evident from the findings that the modes of periodic rolling and static roll have a significant effect on the mixing processes of non-isothermal coolant flows. After analyzing the obtained graphic images, areas of uneven mixing were identified, which are in direct correlation with the conditions of external dynamic influences. The techniques tested in the study of mixing processes of non-isothermal flows can be used in other applications to solve similar problems.

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