Numerical Investigation of the Leakage Flow from a Pressurized CO2 Pipeline

The accidental release of supercritical CO2 is one of the main risks during the pipeline transportation for carbon capture and storage and enhanced oil recovery. The leakage of high pressure CO2 involves phase transition and complex changes of the pressure and temperature fields in the pipelines. A mathematical method for simulating the leakage flow through a crack in a pressurized CO2 pipeline is presented. The validated and accurate method has been employed to simulate the flow inside the pipe, while the leakage flow through the crack was calculated using a capillary tube assumption. In the numerical simulation, a real gas equation of state was employed instead of the ideal gas equation of state. Moreover, results of the flow through the crack and measurement data obtained from laboratory experiments of pressurized CO2 pipeline leakage are compared for the purpose of validation. The pipeline pressure and the leakage flow rates are analysed, which reveal the complex nature of the leakage flow of supercritical CO2 pipeline transport.