Review of Oil–Water Flow Characteristics of Emptying by Water Displacing Oil in Mobile Pipelines

Yan Chen, Guang Li, Jimiao Duan (), Huishu Liu (), Shuo Xu, Yang Guo, Weixing Hua and Junze Jiang
Additional contact information
Yan Chen: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Guang Li: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Jimiao Duan: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Huishu Liu: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Shuo Xu: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Yang Guo: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Weixing Hua: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China
Junze Jiang: Department of Petroleum, Army Logistics Academy, Chongqing 401331, China

Energies, 2023, vol. 16, issue 5, 1-16

Abstract: Water displacing oil is one of the main emptying methods for mobile pipelines. It has the advantages of being a simple process and highly safe. At present, the determination of a water displacing oil scheme of mobile pipelines is based on the oil–oil alternating transport theory of product oil pipelines. However, the insolubility of the oil phase and the water phase results in a great difference between the flow characteristics of water displacing oil and the oil–oil alternating transport of a product oil pipeline. In addition, due to the effect of buoyancy, the oil phase gathers at the high point of the pipeline and forms a liquid accumulation, which is difficult to carry away by water flow, resulting in the low emptying efficiency of the mobile pipeline. The essence of water displacing oil in a mobile pipeline is an oil–water two-phase unsteady displacement flow, involving liquid–liquid displacement flow, oil–water two-phase flow and water carrying oil. Aiming at such problems, domestic and foreign scholars have carried out a large number of theoretical and experimental studies, established the oil–water mixing model of water displacing oil and the relationship between macroscopic quantity (flow pattern, pressure drop and water content) and microscopic quantity (local flow field and droplet dispersion pattern, etc.) under each flow type, and explored the influence of pipeline diameter, oil phase velocity, pipeline inclination angle and other parameters on the capacity of carrying liquid accumulation. On this basis, this paper analyzes the shortcomings of the current research on the oil–water flow characteristics of water displacing oil in a mobile pipeline from three aspects: the formation mechanism of the oil–water mixture, displacing flow characteristics of immiscible fluids and flow characteristics of water carrying oil. Five future research directions are proposed, including the interface morphology and flow field characteristics of oil–water two-phase layered flow, local mixing characteristics of an oil–water two-phase dual continuous flow interface, droplet distribution and flow characteristics of oil–water two-phase dispersed flow, unsteady flow characteristics of the oil–water mixture of water displacing oil and oil accumulation and flow characteristics in topographic relief pipes.

Keywords: mobile pipeline; empty by water displacing oil; flow characteristics (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2023
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/16/5/2174/pdf (application/pdf)
https://www.mdpi.com/1996-1073/16/5/2174/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:16:y:2023:i:5:p:2174-:d:1078701

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().