Application of the digital image correlation algorithms for evaluation of two-phase flow in the heat exchanger

Abstract

The aim of this research work is application of digital image analysis for working out themethod, which will allow to evaluate irregularity rate of two-phase flow across various geometryof tube bundle in aspect of the shell – and – tube heat exchanger optimization. Visualization ofliquid flow in the shell – side enables analysis of flow parameters by the used image processingand analysis methods.Images of two-phase flow were obtained with the use of digital high speed CCD camera, thenwere analysed, to obtain information about hydrodynamics of flow with respect to tube bundlearrangement. Optical techniques of measurement, based on correlation algorithms, allow accuratedetermination of stabilization of velocity fields for the whole field of flow in shell-side, based onthe area size criterion of “still zones” behind rows of tubes. The aim of work was also estimationof the influence of geometrical parameters (tube arrangements, the tube spacings, number of rows)on the homogeneity of two-phase flow in the heat exchangers along with complex analysis offlow area, especially the “still zones”.