Geomechanical Numerical Modeling of Well Wall with in Underbalanced Drilling with Finite Difference Method in Flac۳D

Well, drilling is the only option for the reservoir identification and confirmation of the fluid existence in it. As drilling of oil and gas wells deals with various problems consist of wellbore fall, drilling mud loss, well blowout, and so on, it must by means of such methods can overcome the problems, which are the main concerns of drilling engineering. One of the recommended approaches on the subject is the use of geomechanical relations and construction of the geomechanical model. In this model, useful results can be obtained usage fields’ information, well and well logging data, and applying of geomechanical relations, which on the subject it can be alluded to the window of drilling mud pressure to safe drilling. Regarding after drilling stress distribution in the rock bulk is changed, it is necessary to investigate the stress. To survey the applied tension on the rock bulk FLAC software will be applied to be specified the effect of the stress on the wellbore stability. Then the least and the most mud pressure were specified ۶۰-۸۰ Mpa and ۱۰۰-۱۲۰ Mpa towards different depth, respectively, using wellbore modeling analysis and applying the pressure from mud in the model. In this study, it was discovered that the amounts of well movement in X, Y, and Z have not been the same, and it decreases with becoming away from the wellbore. The maximum of movement amounts in X, Y, and Z are ۱.۵*۱۰-۴, ۴.۲۵*۱۰-۴, and ۱.۲۵*۱۰-۵ meter

Keywords:

Geomechanical model , safe mud window , wellbore stability , stress distribution