CPU-accelerated parallel SPH method for modelling 3D rock hydraulic fracturing problems and its applications

To explore the crack propagation mechanisms of 3D hydraulic fracturing in rocks, a 3D hydro-mechanical coupling crack propagation simulation method based on the Smoothed Particle Hydrodynamics (SPH) framework is proposed, and parallel processing is realized with the help of the OPEN-MP technology. Firstly, the parallel effect evaluation of SPH is carried out. Then numerical simulations of hydro-mechanical coupling crack propagation in rock models with internal fissures are carried out. Results show that: The parallel processing method of SPH based on OPEN-MP technology has achieved remarkable results. The crack propagation processes of single-internal-fissure and double-internal-fissure specimens under hydro-mechanical coupling are analyzed, and it is found that the internal water pressure significantly affects the crack propagation modes. When there is no internal water, multiple types of cracks are generated, and under the action of internal water pressure, the specimens are split due to the penetration of “wing cracks”. The inclination angle of the internal fissure also has a significant impact on crack propagation morphologies. Finally, the fracture mechanisms of rock hydraulic fracturing influenced by the inclination angle and number of fissures are discussed. The research results can provide certain references for the applications of the SPH method in large-scale rock numerical calculations.