“Golden key” to development of unconventional low-permeability reservoirs: FrSmart geo-engineering integrated fracturing design software

Background. The strong heterogeneity, nanodarcy-scale permeability (1—100 nD), and nonlinear flow characteristics of unconventional low-permeability reservoirs result in negligible natural productivity, making hydraulic fracturing the only economically viable development method.

Aim. To address this challenge, the China National Petroleum Corporation (CNPC) has developed the proprietary FrSmart 2.0 solution based on 20 years of research, enabling geo-engineering optimization throughout the fracturing workflow.

Materials and methods. The software integrates nine synergistic modules, including the following. (1) Geomechanical Modeling constructs 1D—3D models using well-log and field data via finite-element algorithms. (2) Artificial Fracture Simulation employs non-planar 3D fracture modeling for complex scenarios (e.g., multi-cluster staged fracturing in horizontal wells). (3) Post-Fracturing Production Prediction leverages Embedded Discrete Fracture Modeling (EDFM) for accurate productivity forecasting and development optimization. (4) Real-Time Decision-Making dynamically analyzes stimulated rock volume (SRV) and fracture morphology using microseismic data. (5) Pre-Fracturing Design optimizes “sweet spot” intervals and cluster placement via entropy weighting and clustering algorithms. (6) Casing Deformation Risk Analysis evaluates fault stability using Mohr-Coulomb failure criteria. (7) Economic Evaluation offers lump-sum and itemized cost models. (8) The Diagnostic Fracturing Tests module determines closure pressure and fluid efficiency. (9) Database Management centralizes proppant, fluid, tubular, and rock mechanics parameters.

Conclusion. FrSmart 2.0 enables less than 5% deviation from international benchmarks and supports GPU acceleration. This software has been deployed at over 2000 workstations across 90% of Chinese oil and gas companies and universities. It has allowed optimization of over 18,200 stages/ intervals with 96% user satisfaction. Its integrated design, high-performance algorithms, and adaptability render FrSmart as a critical domestic solution for enhancing recovery in unconventional low-permeability reservoirs.

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