title: A modelling study of the multiphase leakage flow from pressurised CO2 pipeline.
abstract: The accidental leakage is one of the main risks during the pipeline transportation of high pressure CO2. The decompression process of high pressure CO2 involves complex phase transition and large variations of the pressure and temperature fields. A mathematical method based on the homogeneous equilibrium mixture assumption is presented for simulating the leakage flow through a nozzle in a pressurised CO2 pipeline. The decompression process is represented by two sub-models: the flow in the pipe is represented by the blowdown model, while the leakage flow through the nozzle is calculated with the capillary tube assumption. In the simulation, two kinds of real gas equations of state were employed in this model instead of the ideal gas equation of state. Moreover, results of the flow through the nozzle and measurement data obtained from laboratory experiments of pressurised CO2 pipeline leakage were compared for the purpose of validation. The thermodynamic processes of the fluid both in the pipeline and the nozzle were described and analysed.
authors.affiliation: Department of Safety Science Engineering & State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Xuejin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Safety Science Engineering & State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Kang
authors.initials: K
authors.lastname: Li
authors.affiliation: College of Mechanical Engineering and Automation, Huaqiao University, Jimei, Xiamen 361000, China.
authors.forename: Ran
authors.initials: R
authors.lastname: Tu
authors.affiliation: Department of Safety Science Engineering & State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Yi
authors.affiliation: Department of Safety Science Engineering & State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui 230026, China.
authors.forename: Qiyuan
authors.initials: Q
authors.lastname: Xie
authors.affiliation: Engineering Department, Lancaster University, Lancaster LA1 4YR, United Kingdom. Electronic address: x.jiang@lancaster.ac.uk.
authors.forename: Xi
authors.initials: X
authors.lastname: Jiang
keywords: CO(2); Choked flow; Crack flow; Equation of state; Pipeline transport