The use of PIV methods in the study of two-phase flows in small diameter channels

The PIV (Particle Image Velocimetry) method is one of the optical, non-invasive measurement methods for measuring fluid velocity and it can be used in the study of two-phase gas-liquid flows to determine velocity fields. The velocity distribution of the liquid and gas phases influences the formation of two-phase flow structures and, consequently, the mechanisms of energy and moment exchange in the two-phase flow. The article concerns the application of the PIV method in the assessment of hydrodynamic phenomena occurring during two-phase flow realized in pipe minichannels with internal diameters d > 2 mm. Fluorescent marker particles with a density close to that of water were used in the research. The preliminary tests were carried out on the adiabatic water-air mixture. The research aimed to check the applicability of PIV methods also in non-adiabatic flows. As a result of preliminary studies, the velocity maps of the liquid phase, histograms and velocity profiles in the vertical section of the minichannel tested were obtained