The Study of Hydrodynamics of Slug Flow in 10 Degrees Inclined Pipe Using Electrical Capacitance Tomography Data

ABSTRACT

flow along slightly inclined horizontal pipes is a major in gas-liquid , it is very pronounced in chemical, oil and gas processing industries. In reality, there is no absolute pipe due to the undulating nature/ Topography of the laid pipe .

Very little research has been done in this area because of lack of experimental data. This work is proposed to use raw experimental data from 10 degrees inclined horizontal pipe to analyze the flow properties and pattern.

The experimental data obtained will be analyzed in order to improve the fundamental understanding of the flow regime promoted through them.

The following parameters concerned with slug flow in a slightly inclined horizontal pipe: void fraction in the liquid slug, void fraction in the Taylor bubble, translational velocity, slug frequency, length of liquid slug and Taylor bubble will be determined using processed data obtained from Electrical Capacitance Tomography (ECT).

The correlations from other studies such as Dukler et al(1975) ,Taitel et al (1990) etc will be used to validate the experimental results.

TABLE OF CONTENTS

CHAPTER ONE INTRODUCTION

• General introduction……………. 1
  • Multiphase flow in pipes………….. 1
  • Flow patterns in gas-liquid pipe flow………….. 1
  • Flow patterns in horizontal systems………. 2
  • Flow patterns in vertical ……………….. 3
  • Flow patterns in upward inclined systems…………. 4
• Background to the research……. 5
• Problem statement………... 5
• Aim and objectives……….. 6
  • Aim……………… 6
  • Objectives……………………. 6
• Structure of the thesis….. 6

CHAPTER TWO LITERATURE REVIEW

• Flow patterns in horizontal pipes………………… 8
• Slug flow………………. 11
  • Slug velocity……………. 13
  • Slug holdup……………. 16
  • Slug frequency……….. 20
  • Mean Slug length………… 24

CHAPTER THREE EXPERIMENTATION

• Introduction…….. 27
• Overview of the experimental facility…….. 27
• Description of flow facility…………….. 29
• Flow facility components…………. 31
  • Gas-liquid mixing section…….. 31
  • Gas-liquid separation cyclone……… 32
  • Flow measurement section…….. 32
• Pressure drop calculation………………... 33
• Determination of the characterization parameters……….. 34
  • Translational velocity of a Taylor bubble……… 34
  • Liquid film thickness…… 35
  • Slug frequency……. 35
  • Lengths of the slug unit, the Taylor bubble and the liquid slug….. 35
• Schematic diagram of horizontal pipe…………… 36
• Electrical Capacitance Tomography (ECT)………….. 36
• Experimental measurement used to obtain the parametric characterization of the slug flow regime39

CHAPTER FOUR RESULTS AND DISCUSSIONS

• Introduction……………. 40
• Flow pattern in inclined pipe……………. 40
• Translational (Structure) velocity……… 42
• Pressure drop………………. 45
• Void fraction in liquid slug….. 48
• Void fraction in Taylor bubble……… 53
• Mixture density variation with gas superficial velocity……….. 56
• Lengths of the liquid slug, Taylor bubble and the slug unit….. 57
  • Length of the liquid slug…………………. 57
  • Length of Taylor bubble………………… 58
  • Length of liquid slug unit……… 61

4.9 Slug frequency……. 62

CHAPTER FIVE CONCLUSION AND RECOMMENDATIONS

Conclusion….. 67

NOMENCLATURE……… 71

Greek Symbols……………….. 75

REFERENCES………. 76

APPENDIX………………. 87

INTRODUCTION

Multiphase flows are of great interest to a  large variety of industries. The power generation, nuclear reactor technology, food production, chemical process, petroleum, aerospace, and automotive industries are all driving forces in this complex field.

This work is concerned only with gas-liquid flows in inclined pipes with particular interest towards oil and gas industry applications.

 Multiphase flow in pipes

The mixtures of two fluids in pipes are frequently encountered. Flow instabilities may cause the mixture to arrange itself into different geometric configurations.  These geometric configurations are usually referred to as flow patterns or regimes.

A little reflection will show that the orientation of the pipe makes a difference in the flow regime because of the role played by gravity and the density difference between the two fluids.

Flow patterns in gas-liquid pipe flow

When a gas-liquid mixture flows along a pipe, different flow patterns can be produced, influenced by several variables.  Many flow patterns have been named in vertical, horizontal, and inclined gas/liquid flow in pipes.

REFERENCES

Abdul-Majeed, G. H., (2000), “Liquid slug holdup in horizontal and slightly inclined two- phase slug flow”. Journal of Petroleum Science and Engineering, 27, pp. 29.

Abdulkadir, M., (2011), “Experimental and Computational Fluid Dynamics (CFD) studies of gas-liquid flow in bends” PhD thesis, University of Nottingham, UK.

Andreussi, P., Bendiksen, K. H. and Nydal, O. J., (1993), “Void distribution in slug flow”. International Journal on Multiphase Flow, pp. 817.

Andritsos, N., Williams, L., and Hanratty, T. J., (1989), “Effect of liquid viscosity on the stratified slug transition in horizontal pipe flow”. Int. 1. Multiphase Flow. Vol. 15. NO.6. pp. 877.

Arirachakaran, S., Oglesky, K.D., Malinowsky, M.S., Shoham, O., and Brill, P. (1989), “An analysis of oil-water flow phenomenon in horizontal pipes”, SPE 18836, pp. 235.

StudentsandScholarship Team