An advanced general dominant eigenvalue method of accelerating successive substitution during flash calculation for compositional reservoir model

The efficiency and accuracy of phase equilibrium calculations are essential in compositional reservoir models. Usually, a significant part the computational effort simulations is spent on calculations. nonlinear nature requires an iterative solution procedure. Although successive substitution method (SSM) robust simple to implement, it suffers from slow convergence, especially near critical point mixture. general dominant eigenvalue (GDEM) has been widely used accelerate SSM, but its stability deteriorate as temperature pressure approach point. This paper proposes modified form GDEM improve performance near-critical region. modifications have two aspects. First, liquid fraction mixture added variable when performing acceleration, improving both efficiency. second modification post-calibration step imposed replace conventional criterion, which applied before triggering GDEM. With help step, ensured, more importantly, calculation can be improved. Numerical tests three hydrocarbon mixtures, including different numbers components, show that almost same SSM much higher than Cited as: Wang, X., Wei, D., Zhao, Li, J., Noetinger, B. An advanced accelerating during flash for model. Advances Geo-Energy Research, 2022, 6(3): 241-251. https://doi.org/10.46690/ager.2022.03.07