Use of the Interchange Model to Predict Entrainment in Vertical Annular Flow

Hydrate Deposition Model and Flow Assurance Technology in Gas-Dominant Pipeline Transportation Systems: A Review

“…Therefore, the droplets can move to the tubular sidewall spontaneously through free flight. The calculation of hydrate particle deposition in gaseous phases requires the further extension of the droplet settlement theory in annular flow, and on the basis of previous research, Schadel et al presented an approach to characterize the rate of droplet deposition ( R d ) by the droplet flow rate. The calculation method of the droplet deposition rate is expressed as follows: Assuming that the distribution of droplets in each control volume in the gaseous phases is uniform, the total liquid deposition in the d L length within the d t time is capable of being expressed by the subsequent formula where c is the overall concentration of the droplet, k d is the speed of droplet migration to the tubular sidewall, and W le is the mass flow of droplets in the gaseous phases, which is capable of being obtained from the definition of droplet entrainment.…”

“…Therefore, the droplets can move to the tubular sidewall spontaneously through free flight. The calculation of hydrate particle deposition in gaseous phases requires the further extension of the droplet settlement theory in annular flow, 104 and on the basis of previous research, Schadel et al 105 Energy & Fuels presented an approach to characterize the rate of droplet deposition (R d ) by the droplet flow rate. The calculation method of the droplet deposition rate is expressed as follows:…”

Application of a high-speed laser-induced fluorescence technique for studying the three-dimensional structure of annular gas–liquid flow

“…Typical values of critical film Reynolds number (i.e., liquid Reynolds number below which atomization does not occur) for air-water flow belong to the range 60 to 70 (Dykhno and Hanratty 1996).…”

A probability model for fully developed annular flow in vertical pipes: Prediction of the droplet entrainment

“…Nakazatomi and Sekofuchi [19] obtained an equation for entrainment by assuming that the generation of entrainment is in proportion to the dynamic pressure of the liquid phase and the inertia force of the gas phase, and is in inverse proportion to the surface tension of the liquid phase. Pan and Hanratty [20] improved the previous models [7,21] and developed an equation for entrainment resulting from a balance between the atomization rate of the liquid film and the deposition rate of droplets entrained in the gas. Different from the other entrainment correlations, the model introduced the critical liquid and gas flow rates that are needed for atomization to occur.…”