Numerical simulation and safety evaluation of multi-source leakage of buried product oil pipeline

ABSTRACT

The leakage from a buried oil pipeline has the potential to inflict great economic losses and environmental pollution owing to the long-term and concealment. Therefore, studying the diffusion law and safety evaluation of buried product oil pipeline leakage is critical. In this study, the single-hole and double-hole leakage of buried diesel pipeline are used as examples, and the variation laws of inlet and outlet pressure, flow velocity, flow rate and diffusion range of buried product oil leakage is studied by means of computational fluid dynamics (CFD) method. Then, the risk of multi-source leakage of buried product pipeline is evaluated by analytic hierarchy process (AHP) and fuzzy synthetic evaluation (FSE). The results show that the product oil leakage diffusion in front of the orifice is similar to a jet phenomenon, and the diffusion velocity decreases with the increase of the distance. The maximum flow velocity and stable flow velocity of single-hole leakage are higher than those of double-hole leakage. The flow velocity of the single-hole leakage is stable at 28 m/s and that of the double-hole leakage is 16 m/s and 14 m/s and fluctuates in a small range. When the pipeline leaks, the inlet and outlet pressures change, and the inlet pressure changes 1.6 ~ 1.8 times the outlet pressure. Moreover, the oil leakage from the single and double holes achieved a stable level after 0.4s, and the difference was only 0.008 m³/s. At the initial stage of leakage, the longitudinal diffusion range of double-hole leakage is larger than that of single-hole leakage, but the gap is getting smaller with time, while the vertical diffusion is similar, and the leaked oil reaches the ground almost simultaneously. Finally, the synthetic evaluation of leakage accident risk probability is 81.3%, and the risk level is ‘high.’

KEYWORDS:

• Product oil
• buried pipeline
• multi-source leakage
• diffusion
• safety evaluation

Disclosure statement

The authors have no relevant financial or non-financial interests to disclose.

Ethical approval and consent to participate

Not applicable.

Consent to publish

Not applicable.

Authors contributions

All authors contributed to the study’s conception and design. Hongqing Zhu and Baozhen Zhang conceived and designed the study. The first draft of the manuscript was written by Rongxue Kang and Baozhen Zhang. Baozhen Zhang and Qi Yuan were involved in modelling and data analysis. Qing Zhang and Ximeng Zhou revised the first draft, and all authors commented on previous versions of the manuscript. All authors have read and approved the final manuscript.

Availability of data and materials

All data generated or analysed during this study are included in this published article. The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This study was funded by the National Natural Science Foundation of China (Grant No. 72034004).