Abstract: Hydraulic fracturing process of the heterogeneity rockmass under different perforation angles was simulated using the RFPA2D20Flow. Considering the heterogeneous characteristics of rock in a mesoscale， a seepagestressfailure coupling model was created based on the finite element calculation method. The simulation results show that the maximum principal stress controls the fracture propagation direction no matter how perforation angle changes. With the increase of the perforation angle， a turning fracture becomes more obvious and the turning distance bigger. The best perforation angle area is from 0° to 30°. The numerically simulated results were in agreement with the experimental results.

Key words: heterogeneity, perforation angle, fracture evolution, hydraulic fracturing, numerical simulation