关键词: 低渗透, 非达西渗流, 多相, 井-网格方程, 工程化模拟器, 启动系数

Abstract: A mathematical model for multiphase non-Darcy flow is proposed, and a corresponding finite deference discretization method for this model is also developed, then a well-grid flow equation to simulate non-Darcy flow is deduced. Based on existing black-oil simulator, the simulating methods mentioned above are implemented, which makes the engineering simulator possess the ability to simulate multiphase flow in low permeability reservoir. The two-phase start-up flow parameters can be attained by combining experimental results and oil field performance data. It should make the simulating results accord with production characteristics of low permeability reservoir. By analyzing computation result, differences between forecasting results based on different flow laws are also demonstrated. To measure overall producing state of reservoir, a concept of start-up coefficient is proposed. Preliminary evaluation on well-spacing adaptability for developing permeability of 2×10^-3μm² reservoirs by water flooding is given.

Key words: low permeability, non-Darcy flow, multiphase, well-grid equation, engineering simulator, start-up coefficient