Interfacial area concentration of bubbly flow systems

Although gas–liquid bubbly flows are encountered in various engineering fields, there are very few established theoretical foundations on the interfacial area concentration, which have been supported by extensive experimental data. From this point of view, a simple equation for the interfacial area concentration has been derived from the interfacial area transport equation. The derived theoretical equation has been modified to obtain experimentally supported predictive correlation. The obtained interfacial area correlation was validated by 459 data sets measured in bubble columns and forced convective bubbly flows under various conditions. These data sets covered extensive loop and flow conditions such as channel geometry (circular or rectangular channel), channel hydraulic equivalent diameter (9.0–<f>5500 mm</f>), flow direction (vertical or horizontal flow), superficial gas velocity (0.000788–<f>4.87 m/s</f>), and superficial liquid velocity (0.00–<f>6.55 m/s</f>). The extensive database also covered wide ranges of physical properties such as liquid density (684–<f>1594 kg/m3</f>), liquid viscosity (0.410–<f>21.1 mPas</f>), and surface tension (20.0–<f>75.0 mN/m</f>). An excellent agreement was obtained between the developed semi-theoretical correlation and 459 data within an average relative deviation of <f>±22.0%</f>. [Copyright &y& Elsevier]