Characterization of Interfacial Wave in Annular Flow of Newtonian and Non-Newtonian Fluids Using Image Processing Technology

Abstract

In this paper, the features of interfacial wave in vertical air-water and air-shear-thinning liquid two-phase annular flow are experimentally investigated by using high-speed camera technology. Optimizing the previous image analysis algorithms allows more accurate spatial and temporal variation of interface thickness. Accordingly, the type and evolution characteristics of interfacial waves are defined and discussed in detail. In Addition, the variation of film thickness with time and the frequency spectrum of interface waves are analyzed. Moreover, the relationship between interfacial waves and frictional pressure drop is investigated from the perspective of microscopic morphological characteristics of the interface. The corresponding friction factor for Newtonian and non-Newtonian annular flow are proposed and compared with the existing empirical equations.

Keywords: interfacial wave, annular flow, non-Newtonian fluid, image processing, friction factor