Classification of two-phase flow patterns using multifractal analysis of pressure oscillations

The two-phase flow patterns (air–water) in horizontal square minichannel (3 × 3 mm) has been analysed. The multifractal analysis of pressure drop fluctuations was used for qualitative assessment of two-phase flow patterns. The results of the complexity analysis using the multifractal spectral width ( Δh ) are presented. The proposed method allows us to identify the following two-phase flow patterns: micro-bubbles flow, micro- and minibubbles flow, micro- and mini-bubbles with confined bubbles flow, slug flow, stratified flow. The obtained results confirm that this type of analysis can be considered as an alternative way of identification of two-phase flow patterns in the minichannel. The work also focuses on the discussion of the occurrence and identification of bubbles churns in slugs and churns.