A coherent remedy for the one dimensional two fluid model

An improved one-dimensional two-fluid model with appropriate momentum flux parameters is proposed, which is stable in the whole range of flow regime. A linear stability analysis is performed for a two-phase channel flow described by an improved one-dimensional two-fluid model. For a two-phase flow in a dispersed flow regime, an analytical expression for the growth factor is derived as a function of wave number, void fraction, drag coefficient, and relative velocity. It is demonstrated that the two-phase channel flow can be properly described by the proposed one-dimensional two-fluid model in the whole range of flow regime, while the basic form of the one-dimensional two-fluid model renders the system mathematically ill posed. It is also shown that the proposed model is applicable in a practical range of density ratio