Well geometry is another factor that contributes to the difference in flow pattern. This study aims to calculate the friction factor of two-phase flow in EOR injection wells based on different flow patterns. The friction factor calculated in this study is a function of wellbore temperature, as temperature affects the mixture density and thus the void fraction.
Ultimately, the friction factor of the EOR injection well bore can be calculated using this program by inputting PVT data, which will help optimize the production of the well. He spent his valuable time discussing the details of the friction factor in two-phase flow. Process flow of work for project Process flow of calculation program Temperature and steam quality with depth Effect of pipe ID on friction factor Effect of temperature on friction factor Effect of steam quality on friction factor Effect of pipe roughness on friction factor Effect of pit slope on friction Factor.
Relationships between Temperature, Grade and Friction Factor Effect of Tubing ID on Friction Factor with Different Grades Effect of Tubing Roughness on Friction Factor with Different Grades Label of Well Slope on Friction Factor with Different Grades.
Flow pattern
Depending on the density of the particles and on the continuous liquid phase, gravity can cause the particles to settle or rise.
Pressure loss
Economic considerations are the main reason for high injection rates, resulting in high velocities, which then cause significant friction losses. If friction losses are neglected, any injection speed becomes theoretically possible and thus the possibility of performing heat loss and quality calculations for an injection speed that is impossible due to excessive friction losses. Modeling is approximation in which the physics of the problem is approximated and formulated in a format by analytical or numerical means.
Mechanistic modeling is adopted by taking into account the important processes and neglecting the less important effects. There are many types of mechanistic models available and few of the examples are Beggs and Brill (1973), Hasan and Kabir (J 988) and Ansari et al (1994).
Problem statement
Problem Identification
Significant of project
Objectives
Scope of Study
Relevancy of the Study
Feasibility of the project within the scope and time frame
LITERATURE REVIEW
Analysis of References
The objective of this paper was to present the basis for several mechanical models used in various two-phase flow problems. The objective of this paper is to better understand the pressure drop, flow patterns, and liquid holdup in two-phase downward flow using experiments. This paper was concerned with a model that was introduced in the void fraction for two main flow models that are.
This paper presented a simplified two-phase flow model using a slip flow model to calculate liquid holdup for 4 main flow patterns, which are bubble flow, bubble flow, slug flow, straining flow and circular flow. In this paper, the pressure gradient occurring in flow and gas wells was discussed in order to determine the optimal dimensions of the flow train and to design gas lift devices. In this paper, it was found that the pressure gradient correlation must consist of two parts, one part being the correlation for fluid retention and the other for wall friction.
In this paper, a mathematical model was formulated to describe oil well pipe injection with saturated steam under constant inlet conditions.
Theory
- Liquid Holdup
- Superficial Velocity
- Hasan and Kabir model
- Drift flux model
Flow patterns refer to the distribution of each phase in the pipe relative to the other phase. This is because for horizontal flow, the phases tend to separate due to changes in density and the effect of gravity is low causing the flow pattern to be stratified most of the time. As the gas flow rate increases, the number of bubbles increases, and due to coalescence, the average bubble size increases.
As the gas flow rate is further increased, the larger bubbles become longer and spherical in shape. The liquid phase flows around the outside of the Taylor bubble as a broken film, although the resulting liquid and gas flow is upward. A Taylor bubble is defined as large bubbles of a lighter phase formed by the coalescence of small bubbles under certain fluid flow conditions.
Foam flow is highly unstable because an oscillatory up-down motion occurs in the liquid phase, especially in larger diameter pipes. In small diameter pipes the breakdown of the Taylor bubbles is not so sudden as the transition is more gradual without the appearance of hum. As the gas flow rate is further increased, an upwardly moving undulating annular liquid layer develops at the pipe wall, and the gas flows at a significantly greater velocity in the middle of the pipe.
With a further increase in the gas flow rate, the liquid film becomes increasingly thinner while the number of droplets in the core flow increases. The general drift-flux expression that takes into account the effect of non-uniform flow and concentration profiles, in addition to the effect of the local relative velocity between the phases, was developed by Zuber and Findlay. The effect of the parameter on the predictions depends on the value of the mixture rate.
For simplicity, in the drift-flux model this parameter is set to vary with fluid retention. It was noted that in gas/liquid flow, the increase in the rate of rise of Taylor bubbles with increasing deviation from the vertical for near-vertical systems has been observed by a.
CHAPTER3:METHODOLOGY
- Research Methodology
- Gantt Chart and Key Milestone
- Tools required
- RESULTS AND DISCUSSION
- Flow Pattern Transition
- Void fraction
- Friction Factor
- Computation Algorithm
- Relationship between flow pattern and friction factor
- Parameters analysis
It starts from the input of data to the calculation of the final result which is friction factor. The result of the calculation using Mathematica was plotted in graphs using Microsoft Office Excel. This is because at high gas flow rates, the shear force of the gas on the liquid will pull it upwards, allowing the liquid to flow at the wall of the pipe and the gas in the center of the pipe.
Void fraction is a factor in determining the friction factor because void fraction is a variable in the mixture density calculation. The density of the mixture is the weighted volume average of the two-phase pL and pg and the viscosity is the mass average viscosity of the mixture. The calculation procedure of two-phase flow friction factor done using Hasan and Kabir's model is translated into computer codes using Mathematica calculation software.
A computer program is developed to calculate the friction factor according to the specific flow pattern based on the input data. The final calculation will be in calculating the mixing Reynolds number (Eq. 32) followed by the friction factor (Eq. 31). The final output of the program will show the flow pattern, void fraction and friction factor based on the input data.
In fact, if the flow direction of the liquid film in co-current vertical slug flow is properly investigated, it can be found that it sometimes flows down the walls and the frictional pressure loss can be negative. The speed of the waves appears to be completely controlled by the gas flow rate, while the number of waves is controlled by the liquid velocity. This fact has been recognized by many researchers who have found that the frictional pressure drop in the gas core depends on the shape and amplitude of the waves on top of the liquid film.
For example, Chien and lbele showed that the two-phase frictional pressure drop in annular two-phase downwards is a function of the surface friction factor, the mean surface velocity of the gas, and the waviness of the liquid film. Flood waves near the transition of the slug-to-annular flow pattern are even more difficult to study and predict due to their erratic and unsteady behavior. Different regions of the liquid film are observed simultaneously flowing upwards or downwards.
Measurements of the interfacial friction factor performed by Bharathan, Wallis and Abe showed that the interfacial friction factor is much higher than the values predicted from correlations for disturbed waves.
Effect of Tubing ID on Friction factor
Effect of temperature on friction factor
Effect of Temperature on Friction factor
Effect of quality on friction factor
Effect of Quality on Friction factor
Effect of pipe roughness on friction factor
Effect of Pipe Roughness on Friction factor
Effect of well inclination on friction factor
Effect of Well inclination on Friction factor
Relationship between Temperature, Quality and Friction factorFigure
After the vicinity of 535 and beyond, the friction factor increases with respect to decrease in quality. This shows that the increase in temperature lowers the quality and increases the friction factor.
Sensitivity Analysis
Effect of Tubing 10 on Friction Factor with different Quality{ X)
Effect of Pipe Roughness on Friction Factor with different Quality{X)
Effect of pipe roughness on friction factor of different qualities{X) .. Effect of wellbore slope on friction factor of different qualities{X).
Effect of Well Inclination on Friction Factor with different Quality{X)
CONCLUSIONS AND RECOMMENDATIONS
- Conclusions
The mechanical model of Hasan and Kabir was chosen for use due to the use of a slip flow model in the calculation. The Moody friction factor is based on the pipe roughness and the Reynolds number, and in the case of two-phase flow, the Reynolds number would be the Reynolds number of the mixture. The calculation of mixture density, viscosity and surface tension is done with temperature as an independent factor in the equation.
Well configurations and fluid PVT data play a major effect in determining friction factor in EOR injection wells. Friction factor is lowest in large tube diameter, low temperature, low pipe roughness, high steam quality and in bubbling or slug flow regime. The relationship between flow pattern and friction factor is still not very clear and more in-depth research can be done to analyze the effect flow pattern on friction factor.
After all the analysis of results it can be said that the effect of well slope on friction factor does show an interesting trend. Further research can be done on this matter to find the relationship between well slope and friction factor. Knowing the estimation of friction factor with different well slope and flow patterns will surely help to reduce friction factor in the operating application and thus reduce pressure loss.
1995, "Void Fraction in Bubbly and Slug Flow in Downward Vertical and Inclined Systems," SPE Annual Technical Conference and Exhibition, SPE 26522 A.R.Hasan and C.S.Kabir. 2007, "A Basic Approach to Modeling Two-Phase Flow in a Borehole," SPE Annual Technical Conference and Exposition: SPE. 1989, "Functional Correlations of Saturated Steam Properties for Fully Implicit Simulation of Thermal Reservoirs," SPE Reservoir Engineering: SPE 17094.
APPENDIX A
