Abstract
A brief review is presented for patents in the technical domain of numerical analysis on mechanical behavior of formations of unconventional oil and gas. Three technologies of threedimensional (3D) numerical modeling with Abaqus for geomechanics problems existing in petroleum engineering have been critically reviewed. Case 1 is the 3D numerical calculation of mud-weight windows (MWWs). In this work, an integrated 3D method is used, which combines a one-dimensional (1D) analytical tool with the 3D Abaqus finite element (FE) tool. Case 2 is a 3D method for the optimized design of a stage interval of multi-stage hydraulic fracturing, as well as the optimized design of well spacing for horizontal wells of unconventional oil and gas resources. The so-called “real 3D” means that not only the fracture propagation in the vertical and transverse directions, but also the fracture propagation in the lateral direction, will be calculated. This makes the analysis of fracture propagation a full 3D analysis. Continuum damage mechanics (CDM) is used to investigate the development of crack clouds instead of a single crack. Case 3 provides a numerical investigation into sanding prediction for both openhole and cased hole completion forms. Dual-stress-concentration and interpretation on the total amount of plastic strain are analyzed for sanding prediction with the cased hole completion form. These three cases present technology that was disclosed in recently filed patent applications. A discussion of perspective on further development of techniques under this topic is presented at the end of the paper.
Keywords: Finite element method, geomechanics, hydraulic fracturing, mud-weight window, numerical modeling, optimization, petroleum engineering, sanding prediction.
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