Crack arrest analysis of dense-phase CO2 pipelines reinforced with CFRP wraps using a coupled fluid–structure–damage model

Abstract

Carbon capture, utilization, and storage (CCUS) technologies are widely regarded as critical pathways toward achieving carbon peaking and carbon neutrality goals, where the pipeline transportation of CO₂ plays a pivotal role. Due to the extended decompression plateau of CO₂ in dense-phase or supercritical states, pipeline rupture events can lead to rapid crack propagation because the crack tip pressure cannot be relieved promptly, potentially triggering long-range ductile fracture (RDF) accidents. Therefore, investigating crack propagation control and arrest technologies for CO₂ pipelines holds significant engineering value. In this study, the effectiveness of carbon fiber composite crack arrestors in mitigating crack propagation in dense-phase CO₂ pipelines was systematically evaluated through a combined approach of numerical simulations and full-scale burst tests. Firstly, fracture strain data under multiple stress triaxialities were extracted based on different tensile specimen types to calibrate the Johnson–Cook (J–C) damage model. A finite element model incorporating an initial crack was developed. The coupled Eulerian–Lagrangian (CEL) method was employed to simulate the fluid–structure interaction (FSI) between dense-phase CO₂ decompression behavior and crack propagation, while the Hashin damage criterion was applied to the composite arrestor to accurately capture its failure evolution mechanisms. The crack propagation velocity and path were measured and validated through self-designed full-scale CO₂ pipeline burst tests. Results demonstrated that the external carbon fiber composite arrestor significantly reduced crack propagation speed and length, thereby enhancing the fracture control capacity of dense-phase CO₂ pipelines. The simulation predictions showed good agreement with experimental data, verifying the accuracy and applicability of the developed FSI–damage coupled modeling approach. Furthermore, a parametric study was conducted to systematically analyze the effects of arrestor layer, axial length, and initial pipeline pressure on the arrest performance, and minimum design parameters for crack arrestors were proposed. This study establishes a " CO₂–pipeline damage–composite crack arrestor Hashin damage model" framework, providing theoretical references and engineering guidance for the design and optimization of novel composite crack arrestors for CO₂ pipelines.