Optimizing fluid flow coupling in complex artificial fracture network systems

In order to realize the optimization of main and branch fractures in complex volume artificial fracture network systems,this study used three-linear seepage model and optimal coupling of fracture network,and established the mathematical model of main and branch fractures matching relation under consideration of fracture network.The results show that:in the complex fracture network formed by volume fracturing,there is no non-Darcy effect in main fractures and branch fractures because of three-linear flow;when the seepage ratio is less than 0.1 mD,there is relatively small non-Darcy effect between main and branch fractures,generally less than 5%;when the seepage ratio is higher than 0.1mD,the increase of seepage ratio can improve the influence,the number of fracture increases from 10to 200,along with the increase of permeability non-Darcy effect becomes strong up to more than 50%.The study reveales the authenticity and importance of matching relations between main and branch fractures,which offers a theoretical foundation for field fracturing optimize design of complex hydraulic fracture network.