PSI - Issue 2_A

Reza H. Talemi et al. / Procedia Structural Integrity 2 (2016) 2439–2446

2445

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Reza H. Talemi et al. / Structural Integrity Procedia 00 (2016) 000–000

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Fig. 4. Variation of normalised (a) mode I (opening crack propagation mode) and (b) mode II (shearing crack propagation mode) during crack propagation and pipeline decompression.

The proposed model was successfully verified by comparing its predictions against those obtained from the avail able analytical High Strength Line Pipe approach. Based on the application of the rigorous hybrid fluid-structure interaction model to a realistic API X70 steel CO 2 pipeline containing typical operating at conditions expected in CCS, it was shown that in case of a brittle fracture, the propagating crack is arrested at a short distance along the pipe length following its initiation.

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≈11 0 2 4 6 8 10 0 100 200 300 400 500 600 700 800 Millions Pressure [MPa] Velocity [m/s] CO 2 decompression curve Simulated crack propagation using XFEM+CFD Initial pressure

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( ) ( ) Fig. 5. comparison between the variation of gas pressure versus decompression velocity for CO 2 and the predicted crack velocity during decom pression.