Algorithms for determination of the vector velocity field in a two-phase gas-liquid flow

Abstract

Energy efficiency is a key issue of sustainable development. During the design of industrial devices, it strives to achieve the highest possible energy efficiency. In the industrial systems, two-phase flow is a difficult task, especially the prediction and maintenance of the two-phase flow regime. That is why this research proposes the evaluation and choice of an algorithm that will give a hint of the device design for which the hydrodynamic conditions of the two-phase mixture flow may be evaluated. The tests were carried out in a rectangular vertical narrow channel, as this type of device is in common use. The work aimed to show which algorithm is better for such evaluation. Parameters such as pressure drop, heat, mass, and momentum transfer are influenced by the phase velocity field. Still, various models are used for the determination of the velocity field. Therefore there is a problem of choosing a model that will give the results closest to the real conditions. Flow visualization gives the noninvasive determination of the actual velocity field. An analysis of the velocity field was performed, which showed that for different two-phase flow regimes there are differences for given algorithms. The following algorithms were used to determine the velocity vector field: Adaptive Correlation Method and Adaptive Particle Image Velocity Method were used which are the parts of the general Digital Particle Image Velocimetry. The determination of the velocity fields in the quantitative and qualitative assessment of a given two-phase flow regime was obtained. The result of the research is the evaluation of algorithms for characterization two-phase gas-liquid flow.

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