Semi-Emperical Model to Determine Liquid Velocity and Pressure Loss of Two-Phase Flow in A Horizontal Bend–Part I (Stratified Flow)


stratified flow
pressure loss.

How to Cite

Amir Alwazzan. Semi-Emperical Model to Determine Liquid Velocity and Pressure Loss of Two-Phase Flow in A Horizontal Bend–Part I (Stratified Flow). Int. J. Petrol. Technol. [Internet]. 2015 Apr. 20 [cited 2022 Jun. 30];2(1):29-3. Available from:


The objectives of this study are to conduct a thorough literature review on the subject of multiphase flow through bends and to develop and evaluate a semi-empirical model to determine liquid velocity and pressure loss during stratified gas-liquid flow in a horizontal bend. The model is based on incorporating the momentum balance equations of both phases (air and water). Extensive experiments were carried out to acquire data using air and water in a 0.05 m diameter horizontal pipe simulator with an intermediate bend of 0.5 m radius of curvature.

The results show that due to the disturbance nature of the two-phase flow in general, it is quite convenient to describe the pressure drop in terms of the energy loss. It was also found that stratified flow does not cause a significant change in the energy during the flow along the bend traverse due to its stable nature. The semi-empirical model developed for predicting the superficial water velocity during stratified flow shows an acceptable agreement with the experimental data.

The work presented in this paper may help flow assurance, production, pipeline and process engineers to have reliable design and operations through counting for the losses caused by such components.


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