Modeling on ball migration and seating in a horizontal well with multi-cluster perforations

Ball-throwing temporary plugging fracturing is a new technology for achieving uniform-length fracture in a horizontal well. The migration and seating law of a temporary plugging ball (TPB) in the horizontal well is still not clear. Based on the computational fluid dynamics-discrete phase model coupling method, a three-cluster spiral perforated borehole model is established to analyze the effects of the density, diameter, and number of TPB, fracturing fluid injection rate, and viscosity on the migration and seating behaviors of TPB. The results show that the buoyancy ball and the gravity ball have better sealing effects on cluster 3, which is near the borehole heel, and cluster 1, which is near the borehole toe, respectively. When the diameter of TPB is 1-1.3 times the perforation diameter, the overall plugging effect is better. When the number of TPB is 5/6 times the total number of perforations, the plugging effect at cluster 3 and cluster 1 is better. When the injection rate of fracturing fluid ranges from 0.5 to 2.5 m(3)/min, the plugging efficiency at cluster 3 is higher with a low injection rate. When the viscosity of the fracturing fluid is 20-30 mPa s, cluster 3 and cluster 1 have better plugging effect.