Fully Predictive Model of RCP in Plastics Pipes

Fracture Mechanisms # 2001 Munich

This work presents a 3D coupled solid-fluid model for predicting fast failures in pressurised plastic pipes. It is developed within a unified computational procedure where both solid pipe and pressurising media are discretised using the Finite Volume method. The coupling is achieved across the pipe-fluid interface (pipe bore) via special interpolation procedure. Cohesive zone model, which describes the local separation (fracture) process, is incorporated into the model allowing the prediction of the crack growth along the pipe. The model is qualitatively validated against the Full Scale (FS) experimental observations on gas pressurised MDPE (PE80) 250SDR11 pipe. Predicted pressure and crack histories, crack front shape and behaviour of the pipe during rapid crack propagation (RCP) in general, agree with experimental observations.

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