Onset of intermittent flow: Visualization of flow structures

The transition from stratified to intermittent air-water two-phase flow was investigated experimentally, by visualization and pressure drop signals analyses, in a 30 mm ID pipe. flow’s onset found be mainly dependent on the liquid superficial velocity pipe diameter. Plug flow, Less Aerated Slug (LAS) or Highly (HAS) flows could obtained gas grounds. available models, compared experiments, not predict adequately onset. appearance of slugs revealed peaks signal. Furthermore, it shown that slug frequency correlations were valid zone flow.