As the depth and difficulty of oil and gas exploration and production increases,fracturing is usual-ly needed to be conducted to improve productivity.Perforation and reservoir parameters are the main factors affect-ing the fracturing effect.Benchmarking against the classic true triaxial fracturing simulation test,an extended finite element fracturing model was built.The applicability of the extended finite element model in analyzing the fractu-ring effect was verified and improved.Finally,the influence of perforation and reservoir parameters on the propaga-tion law of induced fractures was analyzed.The research results show that when the perforation angle changes from 0° to 75°,the fracture initiation pressure first decreases and then increases.When the perforation angle is 30°,the fracture initiation pressure is the minimum,i.e.,36 MPa;75°,the maximum,i.e.,41.9 MPa,with a variation amplitude of 16.4%.The fracture width decreases from 0.013 8 m to 0.003 3 m,with a decrease ampli-tude of 76.1%.The fracture length first decreases and then increases,and is the minimum,i.e.,23.54 m at 45° perforation angle,and the maximum,i.e.,25.45 m at 0° perforation angle.When the perforation depth changes from 0.6 m to 1.8 m,the fracture initiation pressure decreases from 47.7 MPa to 39.79 MPa,with a var-iation amplitude of 24.1%;and the variation amplitude of fracture width is less than 4%.When the horizontal ground stress difference changes from 0 MPa to 7 MPa,the fracture initiation pressure increases from 32.97 MPa to 41.04 MPa,an increase of 19.7%;the fracture width decreases from 0.013 12 m to 0.006 86 m,a decrease of 47.7%;the fracture length decreases from 24.5 m to 23.8 m,a decrease of 2.9%.When the elastic modulus changes from 10 GPa to 16 GPa,the fracture initiation pressure changes by 0.43%,and the fracture width and length increase by 25.4%and 35%,respectively.When the tensile strength changes from 1 MPa to 6 MPa,the fracture initiation pressure increases from 37.58 MPa to 48.22 MPa,an increase of 28.3%,the fracture width in-creases by 27%,and the fracture length decreases by 21%.When the elastic modulus changes from 10 GPa to 16 GPa,the fracture width decreases by 17.3%,and the fracture length increases by 23.1%.The research results provide reference for the optimization of fracturing parameters.
fracturingperforation and reservoir parametersboundary extensionfracture initiation pres-surefracture widthfracture length
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