Void fraction predictive method based on the minimum kinetic energy

Abstract

This paper presents a new void fraction predictive method for two-phase gas–liquid flows inside tubes for horizontal and vertical upward flows based on the principle of minimum kinetic energy. Non-uniformities of the velocity profiles are taken into account in the development of the method through empirical factors defined by the momentum coefficients ratio. A regression analysis to correlate the momentum coefficients ratio based on a broad databank gathered from the literature covering horizontal and vertical upward flows is performed. The proposed method has proven more accurate than the current methods available in the literature, as it predicts 92 and 85 % of the experimental data for horizontal and vertical saturated flows, respectively, within a ±10 % error band. The experimental database includes results for saturated flow and covers mass velocities ranging from 70 to 800 kg/m2 s and from 37 to 4500 kg/m2 s and tube internal diameters from 0.5 to 13.8 mm and 6 to 89 mm for horizontal and vertical upward flows, respectively.