Field-Scale Evaluation of Leak Detection for Gas-Liquid Two-Phase Flow in Deepwater Production Systems

2005 ◽  
Author(s):  
John M. Griffin ◽  
John Rogers Smith
Keyword(s):  
Pressure Loss ◽  
Two Phase Flow ◽  
Production Systems ◽  
Average Rate ◽  
Theoretical Method ◽  
Internal Diameter ◽  
Phase Flow ◽  
Field Scale ◽  
Flow Loop ◽  
Two Phase

This paper focuses on validating a theoretical method for the detection of leaks in deep water, multi-phase pipelines. [1] Six field-scale, two-phase flow tests were conducted to compare small leaks with a no-leak condition. These tests qualitatively demonstrate the feasibility of Scott’s concept. Knowing the characteristic pressure loss versus throughput in a line without a leak provides a basis for determining the presence of a leak by measuring pressure loss and flowrate out of the line. If the pressure loss is higher than expected for that flowrate, a leak is a likely possible cause. In these full-scale tests, a leak was readily detectable once the leak rate exceeded 16 percent for the case where the average rate exiting the line was 547 MCFPD. These tests were performed on a 3.64 inch (9.25 cm) internal diameter 9,640 foot (2,938 m) long flow loop with the leak occurring at the midpoint.

Suitability of Eutectic Field’s Metal for Use in an Electromagnetohydrodynamically-Enhanced Experimental Two-Phase Flow Loop

2012 ◽  
Author(s):  
A. Lipchitz ◽  
Lilian Laurent ◽  
G. D. Harvel
Keyword(s):  
Liquid Metal ◽  
Two Phase Flow ◽  
Nuclear Reactors ◽  
Liquid Metals ◽  
Metal Flow ◽  
Phase Flow ◽  
Laboratory Setting ◽  
Flow Loop ◽  
Fast Reactors ◽  
Two Phase

Several Generation IV nuclear reactors, such as sodium fast reactors and lead-bismuth fast reactors, use liquid metal as a coolant. In order to better understand and improve the thermal hydraulics of liquid metal cooled GEN IV nuclear reactors liquid metal flow needs to be studied in experimental circulation loops. Experimental circulation loops are often located in a laboratory setting. However, studying liquid metal two phase flow in laboratory settings can be difficult due to the high temperatures and safety hazards involved with traditional liquid metals such as sodium and lead-bismuth. One solution is to use a low melt metal alloy that is as benign as reasonably achievable. Field’s metal is a eutectic alloy of 51% Indium, 32.5% Bismuth and 16.5% Tin by weight and has a melting point of 335K making it ideal for use in a laboratory setting. A study is undertaken to determine its suitability to use in a two-phase experimental flow loop enhanced by magnetohydrodynamic forces. The study investigated its reactivity with air and water, its ability to be influenced by magnetic fields, its ability to flow, and its ease of manufacture. The experiments melted reference samples of Field’s metal and observed its behaviour in a glass beaker, submerged in water and an inclined stainless steel pipe. Then Field’s metal was manufactured in the laboratory and compared to the sample using the same set of experiments and standards. To determine Field’s metal degree of magnetism permanent neodymium magnets were used. Their strength was determined using a Gaussmeter. All experiments were recorded using a COHU digital camera. Image analysis was then performed on the video to determine any movements initiated by the magnetic field forces. In conclusion, Field’s metal is more than suitable for use in experimental settings as it is non-reactive, non-toxic, simple to manufacture, easy to use, and responds to a magnetic force.

Experimental Comparison of Newtonian and Non-Newtonian Multiphase Flow in Horizontal Pipes

2020 ◽  
Author(s):  
Faraj Ben Rajeb ◽  
Mohamed Odan ◽  
Amer Aborig ◽  
Syed Imtiaz ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Newtonian Fluid ◽  
Two Phase Flow ◽  
Newtonian Fluids ◽  
Theoretical Research ◽  
Experimental Comparison ◽  
Phase Flow ◽  
Flow Loop ◽  
Two Phase ◽  
Mixture Flow ◽  
Pressure Drops

Abstract Two-phase flow of gas/Newtonian and gas/non-Newtonian fluid through pipes occurs frequently in the chemical industry as well as in petroleum refining. Extensive experimental and theoretical research has been carried out on these systems in order to better understand their behaviour under different conditions regarding pressure, temperature and mixture concentrations. In this study, experimental apparatuses are used to investigate two-phase flow of gas/liquid systems through pipes. Air is used as the gas in the experiments, while water is used as the Newtonian fluid and Xanthan gum as the non-Newtonian fluid. The objectives of the study are to compare pressure drops when the same gas flows simultaneously with Newtonian and non-Newtonian fluids through tubes. The comparison here is between experimental pressure drops and estimated pressure drops, based on available empirical correlations for gas/Newtonian and gas/non-Newtonian flow. The trend exhibited by the pressure drops in both systems helps us to better understand the relationship between mixture flow pressure drops in Newtonian and non-Newtonian fluids and thereby develop a new experimental model. The tube diameter for the flow loop is 3/4 inch and the flow type ranges from transient to turbulent.

Investigation of Liquid Loading in Gas Well: Simultaneous Measurements of Drop-Size, Film Thickness and Pressure Drop

2010 ◽  
Author(s):  
Mhunir B. Alamu ◽  
Barry J. Azzopardi ◽  
Gerrit P. van der Meulen ◽  
Valente Hernandez-Perez
Keyword(s):  
Pressure Drop ◽  
Film Thickness ◽  
Drop Size ◽  
Two Phase Flow ◽  
Measurement Instrument ◽  
Dominant Frequency ◽  
Internal Diameter ◽  
Phase Flow ◽  
Two Phase ◽  
Frequency Space

The mechanism of atomization of part of the liquid film to form drops in annular two-phase flow is not entirely understood. It has been observed that drop creation only occurs when there are large disturbance waves present on the film interface. Woodmansee and Hanratty [1] observed that ripples on these waves were a precursor to drops. Though it has been reported that drops occur in bursts by Azzopardi [2], all previous drop size or concentration measurements have always been time integrated to simplify data analysis. Dynamic time averaged drop-size measurements are reported for the first time for annular two-phase flow. Experiments were carried out on a 19mm internal diameter vertical pipe with air and water as fluids. Spraytec, a laser diffraction-based, drop size measurement instrument, was used in the data acquisition. Simultaneous time-resolved measurements were made of: film thickness using conductance probes employing a pair of flush mounted rings as electrodes; and pressure gradient. The gas superficial velocity was 13–43 m/s at liquid superficial velocities of 0.05 and 0.15 m/s. Additional tests were carried out with the gas velocity at 14 m/s for liquid superficial velocities of 0.03–0.18 m/s. Though structures are not clearly visible in the signals acquired, they have been analyzed in amplitude and frequency space to yield Probability Density Function (PDF) and to identify the dominant frequency. Cross-correlation between two film thickness probes provides the wave velocities. Based on the signal analysis, links between film thickness, drop concentration and pressure drop have been identified.

Transition of Bubbly to Slug Flow in a Short Vertical Channel of Gas-Liquid Two-Phase Flow

2014 ◽  
Vol 881-883 ◽  
pp. 721-725
Author(s):  
Mohd Zamri Zainon ◽  
Mohd Ardan Zubir ◽  
Rahizar Ramli
Keyword(s):  
Slug Flow ◽  
Two Phase Flow ◽  
Vertical Channel ◽  
Superficial Velocity ◽  
Phase Flow ◽  
Flow Loop ◽  
Two Phase ◽  
Slip Ratio ◽  
Wide Range ◽  
Simple Flow

Transitions of bubbly to slug flow have been investigated for wide range of flow conditions via visualization technique. The effects of velocities of both phases were examined with variety of combinations and the experimentations were focused on the air-water flow with an industrial scale two-phase flow loop. The results show that the formations of slugs were easy with the increasing gas superficial velocity during a fixed liquid superficial velocity and were difficult when velocity of the liquid phase increases. These transitions were then evaluated using the ratio of velocities of both phases or called the slip ratio and from there a simple flow pattern map was constructed.

Measurement of Pressure Loss Throughout a Clogged Steam Generator Tube Support Plate in Single Phase Flow

2010 ◽  
Author(s):  
Olivier Brunin ◽  
Geoffrey Deotto ◽  
Franck David ◽  
Joe¨l Pillet ◽  
Gilles Dague ◽  
...  
Keyword(s):  
Pressure Loss ◽  
Single Phase ◽  
Experimental Approach ◽  
Two Phase Flow ◽  
Loss Coefficient ◽  
Phase Flow ◽  
Single Phase Flow ◽  
Steam Generators ◽  
Two Phase ◽  
Pressure Loss Coefficient

After a period of several years of operation, steam generators can be affected by fouling and clogging. Fouling means that deposits of sludge accumulate on tubes or tube support plates (TSP). That results in a reduction of heat exchange capabilities and can be modelled by means of a fouling factor. Clogging is a reduction of flow free area due to an accumulation of sludge in the space between TSP and tubes. The increase of the clogging ratio results in an increase of the overall TSP pressure loss coefficient. The link between the clogging ratio and the overall TSP pressure loss coefficient is the most important aspect of our capability to accurately calculate the thermal-hydraulics of clogged steam generators. The aim of the paper is to detail the experimental approach chosen by EDF and AREVA NP to address the calculation uncertainties. The calculation method is classically based on the computation of a single-phase (liquid-only) pressure loss coefficient, which is multiplied by a two-phase flow factor. Both parameters are well documented and can be derived on the basis of state of the art methods such as IDEL’CIK diagrams and CHISHOLM formula. The experimental approach consists of a validation of the correlations by performing tests on a mock-up section with an upward flow throughout a vertical array of tubes. A mixture of water and vapour refrigerant R116 is used to represent two-phase flows. The tube bundle is composed of a 25 tubes array in a square arrangement. The overall height of the mock-up is 2 m. Eight test TSPs were manufactured, considering eight different clogging configurations: six plates with a typical clogging profile at six clogging ratios (0, 44%, 58%, 72%, 86%, 95%), and two plates with a clogging ratio of 72% associated with two different clogging profiles (large bending radius profile and rectangular profile). A series of tests were performed in 2009 in single-phase flow conditions. Two-phase flow tests with a mixture of liquid water and vapour refrigerant R116 will be performed in 2010. The paper illustrates the main results obtained during the single-phase tests performed in 2009.

Effects of Curved Section on Gas-Liquid Two-Phase Flow in Milli-Channel

2013 ◽  
Author(s):  
Kazuki Takeda ◽  
Shinpei Okamoto ◽  
Kenji Yoshida ◽  
Isao Kataoka
Keyword(s):  
Pressure Loss ◽  
High Speed ◽  
Two Phase Flow ◽  
Flow Behavior ◽  
Narrow Channel ◽  
Phase Flow ◽  
Straight Section ◽  
Industrial Products ◽  
Two Phase ◽  
Curved Section

In recent years, we can easily find the gas-liquid two-phase flow in narrow channel which has straight section and curved section in many industrial products. In order to improve the performance of these industrial products, it is important to clarify the effects of curved section on gas-liquid two-phase flow behavior in narrow channel. In this study, we have measured the pressure loss precisely on straight section and curved section in milli-channel respectively. From the measured pressure loss, we evaluated the mean pressure loss and its intensity. Flow visualization by using high-speed video camera was additionally performed to make clear the relation between modification of pressure loss and flow pattern in curved section. As a result, effects of curved section on gas-liquid two-phase flow in narrow channel were evaluated.

Void Fraction Measurements for Air-Water Pipe Flows Using Quick-Closing Valves and Wire-Mesh Sensors

2018 ◽  
Author(s):  
Étienne Lessard ◽  
Jun Yang
Keyword(s):  
Void Fraction ◽  
Test Section ◽  
Two Phase Flow ◽  
Measurement Techniques ◽  
Wire Mesh ◽  
Axial Distance ◽  
Phase Flow ◽  
Flow Conditions ◽  
Flow Loop ◽  
Two Phase

In support of a header/feeder phenomena study, an adiabatic, near-atmospheric, air-water flow loop was commissioned simulating a single feeder of a Pressurized Heavy Water Reactor’s primary heat transport system under a postulated Loss of Coolant Accident scenario. An extensive database in representative two-phase flow conditions was collected, 750 tests in total, in order to create a two-phase flow map to be used in the more complex geometries such as header/feeder systems. The flow loop consists of two vertical test sections, for upwards and downwards flow, and one horizontal test section, each with an inner diameter of 32 mm and at least 120 diameters in length. Superficial velocities extended up to 6 m/s for the water and 10 m/s for the air. Void fraction was measured by means of quick-closing valves and a pair of wire-mesh sensors (WMS) in each test section. Two-phase repeatability tests showed that the liquid and gas superficial velocities varied by 1.1% and 0.6% at reference conditions of 2.0 and 2.8 m/s, respectively. The corresponding void fraction measurements varied for the quick-closing valves by at most 6.8%, which indicates a low sensitivity to the closure time of the valves and an appropriate axial distance between them, and 2.3% for the WMS. For both measurement techniques, the largest variations occurred in the vertical downwards test section. For the formal two-phase tests, over 600 distinct flow conditions were performed. The results showed that the two measurement techniques agreed within 5% at high void fractions and low liquid flow rates in vertical flow. For all other cases corresponding to the transitional or dispersed bubbly flow regime, the WMS over-estimated the void fraction by a consistent bias. An empirical correction is proposed, with a root-mean-square error of 6.6% across all tests. The void fraction map resulting from this database provides validation for the WMS measurements, a quantitative assessment of its uncertainty and range of applicability, and will be used as a reference in future tests under similar scale and flow conditions.

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