Counter current gas-liquid vertical flow, model for flow pattern and pressure drop

Counter-current flow pattern transition and pressure drop are modeled. Emphasis is placed on the understanding of the transition mechanisms from a mechanistic point of view.

Unlike the case of co-current flow, in counter-current flow, the situations of “no solution” as well as “multiple solutions” for the flow pattern and pressure drop exist. These possibilities are discussed and criteria for the actual flow pattern that will take place are suggested.

Some of the results are supported by data (from the literature), others are somewhat tentative suggesting future experimental verification is needed.