Model study initiation angle of fracture under refracturing

Considering the pore pressure of injection/production around the refracturing well under coupling liquid/solid, mathematical models are established to describe the maximum principal stress and orientation angle of maximum principal stress induced by pore pressure around refracturing wells. Considering that the initial artificial fracture is full of incompetent and compressible fluid, affection efficient of fluid is presented; the model of stress field induced by initial artificial fracture is established. According to the linear superimposition law, model of stress field distribution around refracturing well is established. According to the breakdown formula of the crack, model of initial angle of refracturing is set up. The refracturing initial angle variation range is obtained. Both the calculation and the production results of two refracturing wells are compared, which shows that the calculation of the refracturing initial angle is accurate, and the method is practical.