On the Feasibility of Heat Removal from Generator/ Transmitter Units for Assumed 10MW Space Solar Power System by Using Two-phase Flow Loop with Latent Heat Transportation

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.

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

Volume 2: Fluid Mechanics; Multiphase Flows ◽

10.1115/fedsm2020-20236 ◽

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.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.721 ◽

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.

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

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2005-77372 ◽

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.

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

Volume 2: Development and Applications in Computational Fluid Dynamics; Industrial and Environmental Applications of Fluid Mechanics; Fluid Measurement and Instrumentation; Cavitation and Phase Change ◽

10.1115/fedsm2018-83405 ◽

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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Problems in Development of Compact Two-Phase Flow Loop for Microgravity Experiments

The proceedings of the JSME annual meeting ◽

10.1299/jsmemecjo.2002.4.0_215 ◽

2002 ◽

Vol 2002.4 (0) ◽

pp. 215-216

Author(s):

Atsushi OKAMOTO ◽

Atsushi BABA ◽

Shogo KOKUBO ◽

Toshiyuki SUZUKI ◽

Haruo KAWASAKI ◽

...

Keyword(s):

Two Phase Flow ◽

Phase Flow ◽

Flow Loop ◽

Two Phase ◽

Microgravity Experiments

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Velocities Effects on the Void Fraction Distribution in a Vertical Gas-Liquid Two-Phase Flow Channel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.889-890.369 ◽

2014 ◽

Vol 889-890 ◽

pp. 369-373

Author(s):

Mohd Zamri Zainon ◽

Mohd Ardan Zubir ◽

Rahizar Ramli

Keyword(s):

Void Fraction ◽

Two Phase Flow ◽

Flow Channel ◽

Phase Flow ◽

Flow Loop ◽

Two Phase ◽

Void Fractions ◽

Conductance Method ◽

Wide Range ◽

Fraction Distribution

Measurement of void fraction in a vertically arranged gas-liquid two-phase flow channel has been conducted for wide range of flow conditions using a specially developed sensor based on electric conductance method. The effects of velocities of both phases were examined with variety of combinations using an industrial scale two-phase flow loop. The results show that at a constant rate of liquid superficial velocities the void fractions increases with the increasing gas superficial velocities and at higher velocities of liquid phase, the value of void fraction becoming lower. The average void fractions were also compared with other scholars results.

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