Experimental Investigation on Flow Characteristics of Aqueous Foams through the Jet Device and Horizontal Pipe

Aqueous foam is regarded as a versatile medium in numerous scientific and engineering applications due to its high viscosity and low density. The objective of this study is to investigate the flow characteristics of aqueous foams through the jet device and horizontal pipe. The pressure distribution and foam production capacity are measured at different operating conditions. Experimental results show that the pressure fluctuations reduce significantly by increasing the foam liquid concentration, especially in the downstream of jet device. The bubble flow turns into homogeneous foams gradually when the concentration increases from 0.025% to 0.35%, while the foam behaviors take little change at a higher concentration, and the foamability reaches a limit. Subjected to the large pressure difference produced between the top and bottom of horizontal pipe, aqueous foams undergo a gas–liquid separation at a high terminal pressure, resulting in bubbles at the top and liquid at the bottom. Therefore, the terminal pressure should be kept less than a critical value to hold a good foam pattern. Based on the above contributions, it is believed that the study laid an important foundation for the widespread application of foam technology.