Analysis of the water‐filling process for crude oil pipelines with a large drop in height

Abstract

To explore the problem of the slack flow and waterhead having a huge impact on the low point of a pipeline during the water-filling process of a large-drop pipeline, the crossing section of the Nujiang China-Myanmar crude oil pipeline (for which the maximum height difference is 1480 m) is taken as an actual case, and water filling of an oil pipe segment with a large drop is simulated based on an OLGA multiphase flow transient simulation. The maximum velocity, pressure, and corresponding liquid holdup at different low points of the pipeline are studied, and the variations of water flow velocity, pressure, and liquid holdup with time at different low points under different load conditions are obtained. A stress analysis of the pipeline is performed through CAESAR II. The results showed that, when the volume flow rate was 900-2000 m 3 /h, the probability of slug flow in pipe could be reduced by 57%. Meanwhile, the tube pressure fluctuation and damage to the pipeline and equipment are reduced and pipeline transportation efficiency is improved, thereby providing an effective basis for engineering practice.

Numerical simulation and simplified calculation method for heat exchange performance of dry air cooler in natural gas pipeline compressor station

“…When solving the air cooler outlet temperature, it is only necessary to solve the temperature drop value of the air cooler to the hot fluid natural gas by fitting the formula, instead of performing a large number of iterative calculations based on the heat transfer calculation process, which greatly simplifies the heat transfer calculation process. The method used in this article can be used not only for the calculation of natural gas pipeline systems, but also for the analysis of the production process of oil and gas pipelines, [39][40][41] and the analysis and calculation of air coolers in gas storage systems. [42][43][44]…”

Performance evaluation of multiple fractured horizontal wells in shale gas reservoirs

“…1,2 To analyze the characteristics of fluid flow in shale gas reservoirs, many mathematical models were established and solved. 3,4 Due to the low permeability and porosity and complicated flow characteristics in shale reservoirs, horizontal well and volume fracturing technology are used to improve gas well productivity. In general, there are differences in fluid flow ability between shale matrix and fractures, and these differences were taken into consideration to analyze the fluid flow characteristics in shale gas reservoirs.…”

“…Twenty percent to eighty percent of the shale gas is absorbed into the matrix surface, and the rest in pores and fractures as free gas 1,2 . To analyze the characteristics of fluid flow in shale gas reservoirs, many mathematical models were established and solved 3,4 . Due to the low permeability and porosity and complicated flow characteristics in shale reservoirs, horizontal well and volume fracturing technology are used to improve gas well productivity.…”

Research on the steady‐state operation optimization technology of oil pipeline

“…1 At present, there are many problems in oil and gas pipelines, including the mechanism of oil mixing, flow noise, and particle deposition. [2][3][4][5][6][7][8][9][10] The energy consumption of the hot oil pipeline system is also the focus of many scholars' research. Through a lot of literature research, we can set the energy consumption of the pipeline system in the following two directions:…”