A Simple Model for Predicting the Two-Phase Heavy Crude Oil Horizontal Flow with Low Gas Fraction

Abstract

A two-phase heavy crude oil flow with low gas fraction is common in the oil transportation process. However, most of the studies of a gas–liquid flow are based on low viscosity fluid, such as water and light oil; as a result, the results cannot be introduced successfully into the mixture flow of gas and heavy crude oil. In this work, a two-phase flow of gas and heavy crude oil, which originated from the Bo-hai oilfield in China, was investigated in a horizontal pipe with 47-mm inner diameter. Data were acquired for the oil flow rate ranging from 2 m³/h to 10 m³/h, the input gas volume fraction ranging from 0.01 to 0.15, and the viscosity of crude oil ranging from 2.41 Pa·s to 0.34 Pa · s. Based on the drift-flux model, a new simplified correlation was developed to predict the void fraction and the pressure gradient. A comparison between the predicted and measured data demonstrates a reasonable agreement, and the correlation might be helpful for practical application in industry, especially in initially estimating the flow characteristic parameters.

Keywords:

• Drift-flux model
• Gas–liquid flow
• Heavy crude oil
• Pressure gradient
• Viscosity
• Void fraction