窜流通道高速非达西渗流规律实验

EXPERIMENT IN HIGH-SPEED NON-DARCY FLOW LAWS IN CROSS FLOW CHANNELS

我国大部分油田目前都处在高含水或特高含水开发阶段，各种动态监测分析表明，微观上油藏的特定部位形成了几十倍，甚至数百倍于原始孔道的窜流通道。窜流通道引起的注水低效、无效循环问题已经成为制约油田高效开发、提高原油采收率的主要矛盾。目前，国内外对非线性渗流的研究仍存在很大局限性，而考虑高速非达西渗流的研究更少。以高渗透性填砂管模型为实验对象，设计了窜流通道渗流规律物理模拟实验。根据实验结果，建立了适用于不同级别窜流通道的非达西流系数关系式，揭示了高渗多孔介质的非达西流系数与渗透率、孔隙度之间的内在联系，并在此基础上，进一步研究了达西流向非达西流过渡的临界流速。

At present, most of the oilfields in China have been in high-water cut or extra-fhigh watercut develop- ment stage. All kinds of dynamic monitoring analyses show that cross-flow channels decades and even hundreds times larger than original pore and channel size are microscopically formed in specified parts of the oil reservoir. The resulted low-efficiency water injection, no-effect cycle problems have already been the major contradictions to constrain the high-efficiency development and enhancing recovery of the oilfields. Nowadays, there are still great limitations in the studies on non-linear flow at home and abroad, and the studies on high-speed non-Darcy flow are even less considered. Taking high permeability sand-filled tube model as an experimental object, the physical simu- lation experiment on the flow laws of cross channels is designed based on percolation mechanics. According to the experimental results, the relation expressions with non-Darcy flow coefficient for different grades of cross flow channels are established, and then the interior links among the coefficient, permeability and porosity in high-permeability porous media have been exposed; and moreover, on the basis of the above, the critical flow rate transformed from Darcy flow to non-Darcy flow is researched.