the michelsen stability and multiphase flash calculation by direct minimization of gibbs free energy of the system at constant temperature and pressure, was used for systems containing gas hydrates. the solid hydrate phase was treated as a solid solution. the fugacities of all components of the hydrate phase were calculated as a function of compositions by the rearranged model of van der waals ...

The Michelsen stability and multiphase flash calculation by direct minimization of Gibbs free energy of the system at constant temperature and pressure, was used for systems containing gas hydrates. The solid hydrate phase was treated as a solid solution. The fugacities of all components of the hydrate phase were calculated as a function of compositions by the rearranged model of van der Wa...

For some of the EOS models the dimension of equilibrium problem can be reduced. Stability and difficulties in implementation are among the problems of flash calculation. In this work, a new reduction technique is presented to prepare a reduced number of equilibrium equations. Afterwards, a number of appropriate solution variables are selected for the prepared equation system to solve the equati...

a numerical framework has been proposed to model the interacting effects of mixture non-ideality and mass transfer on hydrodynamics of a multiphase system using cfd methods.mass transfer during condensation and vaporization is modeled by chemical potential at the liquid-vapor interface. species mass transfers are related to the diffusion at the interface which in turn is related to the concentr...

By the analysis on traditional methods for rules of flash metal consume design, the idea of regression mining for flash metal consume design is proposed. Then according to related definitions, we construct a linear regression model. Its parameter estimation method and significant test methods of linear correlation are discussed in detail. We also analyze the method of applying mathematical stat...

A general and polyvalent model for the dynamic simulation of a vapor, liquid, liquid-liquid, vapor-liquid or vapor-liquid-liquid stage is proposed. This model is based on the τ -method introduced as a minimization problem by Han & Rangaiah (1998) for steady-state simulation. They suggested modifying the mole fraction summation such that the same set of governing equations becomes valid for all ...

PFLOTRAN a massively parallel computer code for modeling coupled hydro-thermalchemical processes in variably saturated, non-isothermal porous media is applied to sequestration of supercritical CO2 in deep geologic formations. Two different methods of solution to the governing partial differential equations are implemented referred to as variable switching and the flash approach. Variable switch...