基于有限体积法的离散裂缝模型两相流动模拟

正确认识裂缝性油藏流体流动规律是其高效开发的基础，离散裂缝模型因其对裂缝予以显式降维处理，能够大大提高计算效率而逐渐成为当前研究的热点。有限体积法在控制体单元上具有明确的物理意义，能够严格保证局部质量守恒，适用于流场性质不连续的情况。基于Delaunay 三角网的对偶网格构建有限体积控制单元，推导了离散裂缝模型油水两相流动控制方程的有限体积数值计算格式，实现了离散裂缝模型油水两相数值模拟，通过算例验证了该方法的正确性与高效性。研究表明：该方法能够严格保证局部质量守恒，计算过程中收敛性较好，适用于离散裂缝油藏的数值模拟，与单孔隙介质模型计算结果具有很好的一致性，计算效率提高2.5∼3.0 倍。

Study on Discrete Fracture Model Two-phase Flow Simulation Based onFinite Volume Method

Correctly recognizing the flowing rules of fractured reservoir is the foundation of high development efficiency. Discretefracture model has become a research hot spot，because it can explicitly simplify fracture by using reduction dimensionalmethod，which can greatly improve computing efficiency of the numerical simulation. Finite volume method has a clear physicalmeaning in every control volume，and can ensure local mass conservation strictly，so it is appropriate for the situation ofdiscontinuous flow field. In this paper，we use the median dual of Delaunay triangular mesh to control the volume cell，establishthe numerical computational scheme of discrete fracture model，study on oil-water two phase numerical simulation of discretefracture model，and verify the correctness and efficiency of theory and algorithms through examples. The results show that thismethod can ensure local mass conservation strictly，and the convergence is better in the process of the calculation. It is wellsuitable for fractured reservoir simulation，and has very good consistency with single porous medium model，the computingefficiency improved 2.5∼3.0 times.