Derivation of the Basic Equations and Simplified Transport Models of the Interfacial Area in Gas-Liquid Two-Phase Flow

Rigorous and consistent formulations of basic equations of interfacial area transport were derived using correlation functions of the characteristic function of each phase and velocities of each phase. The turbulent transport term of interfacial area concentration was consistently derived and related to the difference between the interfacial velocity and the averaged velocity of each phase. Constitutive equations of turbulent transport terms of interfacial area concentration were proposed for bubbly flow. New transport model and constitutive equations were developed for churn flow. These models and constitutive equations are validated by experimental data of radial distributions of the interfacial area concentration in bubbly flow and churn flow.