Development of a friction factor correlation for a foam flow in a horizontal circular pipe

A series of experiments was conducted to investigate the flow of aqueous foam and the associated frictional pressure drop over a foam quality range of 0.170 to 0.908. Various foam flow regimes were observed, including wet foam, wet-dry mixed foam, transitional slug-wet foam, and slug-wet foam. These regimes varied even at identical foam qualities, depending on the gas and liquid velocities. The frictional pressure drops were measured across different foam flow regimes, exhibiting variation based on foam quality, as well as liquid and gas flow rates. An empirical correlation for the Fanning friction factor of foam flows was developed, demonstrating superior agreement with two independent experimental data sets, with an error margin of ±5.4 %. These findings offer valuable insights into foam flow behavior and frictional pressure losses in horizontal pipes, which are critical for optimizing decontamination processes in nuclear facilities.