Experimental Study of DRA for Vertical Two-Phase Annular Flow

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
R. L. J. Fernandes ◽  
B. A. Fleck ◽  
T. R. Heidrick ◽  
L. Torres ◽  
M. G. Rodriguez
Keyword(s):  
Pressure Gradient ◽  
Drag Reduction ◽  
Production Rate ◽  
Annular Flow ◽  
Liquid Holdup ◽  
Two Phase ◽  
High Production Rate ◽  
High Production ◽  
Feasibility Test ◽  
Main Effects

Experimental investigation of drag reduction in vertical two-phase annular flow is presented. The work is a feasibility test for applying drag reducing additives (DRAs) in high production-rate gas-condensate wells where friction in the production tubing limits the production rate. The DRAs are intended to reduce the overall pressure gradient and thereby increase the production rate. Since such wells typically operate in the annular-entrained flow regime, the gas and liquid velocities were chosen such that the experiments were in a vertical two-phase annular flow. The drag reducers had two main effects on the flow. As expected, they reduced the frictional component of the pressure gradient by up to 74%. However, they also resulted in a significant increase in the liquid holdup by up to 27%. This phenomenon is identified as “DRA-induced flooding.” Since the flow was vertical, the increase in the liquid holdup increased the hydrostatic component of the pressure gradient by up to 25%, offsetting some of reduction in the frictional component of the pressure gradient. The DRA-induced flooding was most pronounced at the lowest gas velocities. However, the results show that in the annular flow the net effect will generally be a reduction in the overall pressure gradient by up to 82%. The findings here help to establish an envelope of operations for the application of multiphase drag reduction in vertical flows and indicate the conditions where a significant net reduction of the pressure gradient may be expected.

scholarly journals Isotope separation of 176Lu a precursor to 177Lu medical isotope using broadband lasers

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
M. V. Suryanarayana
Keyword(s):  
Production Rate ◽  
Isotope Separation ◽  
Medical Applications ◽  
Optimum Conditions ◽  
High Production Rate ◽  
Laser Isotope Separation ◽  
High Production ◽  
System Requirements ◽  
Medical Isotope ◽  
Rhodamine Dye

AbstractA new photoionization scheme accessible by Rhodamine dye lasers is proposed for the isotope separation of 176Lu.$$5d6s^{2}\,{^{2}D_{{3/2}}} (0.0\, {\text{cm}}^{{ - 1}} )\mathop{\longrightarrow}\limits^{{573.8130\, {\text{nm}}}}5d6s6p\,{^{4}F_{{3/2}}^{o}} \left( {17427.28\, {\text{cm}}^{{ - 1}} } \right)\mathop{\longrightarrow}\limits^{{560.3114\, {\text{nm}}}}$$ 5 d 6 s 2 2 D 3 / 2 ( 0.0 cm - 1 ) ⟶ 573.8130 nm 5 d 6 s 6 p 4 F 3 / 2 o 17427.28 cm - 1 ⟶ 560.3114 nm $$6s{6p}^{2}\,{^{4}{P}_{5/2}}\left(35274.5 \,{\text{cm}}^{-1}\right){\to } Autoionization\, State {\to }{Lu}^{+}$$ 6 s 6 p 2 4 P 5 / 2 35274.5 cm - 1 → A u t o i o n i z a t i o n S t a t e → Lu + Optimum conditions for the laser isotope separation have been theoretically computed and compared with the previously reported work. The enrichment of ~ 63% can be obtained with > 22 mg/h production rate even when broadband lasers with bandwidth of 500 MHz are employed for the two step excitation. The simplified system requirements for the photoionization scheme combined with a high production rate of 176Lu than previously reported is expected to reduce the global shortage of 176Lu isotope for medical applications.

scholarly journals Can Frequency Account for the Grammatical Choices of Children and Adults in Nominal Modification Contexts? Evidence from Elicited Production and Child-Directed Speech

Languages ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. 35
Author(s):  
Emanuela Sanfelici ◽  
Petra Schulz
Keyword(s):  
Language Acquisition ◽  
Production Rate ◽  
Relative Clauses ◽  
Language Use ◽  
Spontaneous Speech ◽  
Production Task ◽  
Specific Context ◽  
High Production Rate ◽  
High Production ◽  
Acquisition Order

There is consensus that languages possess several grammatical variants satisfying the same conversational function. Nevertheless, it is a matter of debate which principles guide the adult speaker’s choice and the child’s acquisition order of these variants. Various proposals have suggested that frequency shapes adult language use and language acquisition. Taking the domain of nominal modification as its testing ground, this paper explores in two studies the role that frequency of structures plays for adults’ and children’s structural choices in German. In Study 1, 133 three- to six-year-old children and 21 adults were tested with an elicited production task prompting participants to identify an agent or a patient referent among a set of alternatives. Study 2 analyzed a corpus of child-directed speech to examine the frequency of passive relative clauses, which children, similar to adults, produced very often in Study 1. Importantly, passive relatives were found to be infrequent in the child input. These two results show that the high production rate of rare structures, such as passive relatives, is difficult to account for with frequency. We claim that the relation between frequency in natural speech and use of a given variant in a specific context is indirect: speakers may opt for the less grammatically complex computation rather than for the variant most frequently used in spontaneous speech.

Numerical Investigation on Multiphase Erosion-Corrosion Problem of Steel of Apparatus at a Well Outlet in Natural Gas Production

2018 ◽  
Vol 140 (12) ◽  
Author(s):  
Zhang Jianwen ◽  
Jiang Aiguo ◽  
Xin Yanan ◽  
He Jianyun
Keyword(s):  
Fluid Flow ◽  
Natural Gas ◽  
Production Rate ◽  
Gas Production ◽  
Two Phase ◽  
Gas Well ◽  
Chemical Corrosion ◽  
High Production Rate ◽  
Erosion Corrosion ◽  
Corrosion Problem

The erosion-corrosion problem of gas well pipeline under gas–liquid two-phase fluid flow is crucial for the natural gas well production, where multiphase transport phenomena expose great influences on the feature of erosion-corrosion. A Eulerian–Eulerian two-fluid flow model is applied to deal with the three-dimensional gas–liquid two-phase erosion-corrosion problem and the chemical corrosion effects of the liquid droplets dissolved with CO2 on the wall are taken into consideration. The amount of erosion and chemical corrosion is predicted. The erosion-corrosion feature at different parts including expansion, contraction, step, screw sections, and bends along the well pipeline is numerically studied in detail. For dilute droplet flow, the interaction between flexible water droplets and pipeline walls under different operations is treated by different correlations according to the liquid droplet Reynolds numbers. An erosion-corrosion model is set up to address the local corrosion and erosion induced by the droplets impinging on the pipe surfaces. Three typical cases are studied and the mechanism of erosion-corrosion for different positions is investigated. It is explored by the numerical simulation that the erosion-corrosion changes with the practical production conditions: Under lower production rate, chemical corrosion is the main cause for erosion-corrosion; under higher production rate, erosion predominates greatly; and under very high production rate, erosion becomes the main cause. It is clarified that the parts including connection site of oil pipe, oil pipe set, and valve are the places where erosion-corrosion origins and becomes serious. The failure mechanism is explored and good comparison with field measurement is achieved.

scholarly journals Rapid Turnover and High Production Rate of Myeloid Cells in Adult Rhesus Macaques with Compensations during Aging

2018 ◽  
Vol 200 (12) ◽  
pp. 4059-4067 ◽  
Author(s):  
Ziyuan He ◽  
Carolina Allers ◽  
Chie Sugimoto ◽  
Nursarat Ahmed ◽  
Hideki Fujioka ◽  
...  
Keyword(s):  
Production Rate ◽  
Rhesus Macaques ◽  
Myeloid Cells ◽  
Rapid Turnover ◽  
High Production Rate ◽  
High Production

High production rate of crystallization process in TFA-MOD method for YBCO coated conductors

2006 ◽  
Vol 445-448 ◽  
pp. 553-557
Author(s):  
Ryo Teranishi ◽  
Sukeharu Nomoto ◽  
Junko Matsuda ◽  
Yuji Aoki ◽  
Koichi Nakaoka ◽  
...  
Keyword(s):  
Production Rate ◽  
Crystallization Process ◽  
Coated Conductors ◽  
High Production Rate ◽  
High Production ◽  
Ybco Coated Conductors

Designing compartmentalized hydrogel microparticles for cell encapsulation and scalable 3D cell culture

2015 ◽  
Vol 3 (3) ◽  
pp. 353-360 ◽  
Author(s):  
Yen-Chun Lu ◽  
Wei Song ◽  
Duo An ◽  
Beum Jun Kim ◽  
Robert Schwartz ◽  
...  
Keyword(s):  
Cell Culture ◽  
Production Rate ◽  
3D Cell Culture ◽  
Cell Encapsulation ◽  
Uniform Size ◽  
Size And Shape ◽  
Hydrogel Microparticles ◽  
High Production Rate ◽  
High Production

Compartmentalized hydrogel microparticles with high production rate, uniform size and shape, and tunable ECM support were developed for various scalable 3D cell culture applications.

CFD Simulation of Two-Phase Vertical Annular Flow in Both Upward and Downward Direction in a Small Pipe

2019 ◽  
Author(s):  
Ekhwaiter Abobaker ◽  
Abadelhalim Elsanoose ◽  
John Shirokoff ◽  
Mohammad Azizur Rahman
Keyword(s):  
Film Thickness ◽  
Multiphase Flow ◽  
Pressure Gradient ◽  
Annular Flow ◽  
Cfd Simulation ◽  
Flow Direction ◽  
Flow Behavior ◽  
Two Phase ◽  
Downward Flow ◽  
Disturbance Wave

Abstract Computational fluid dynamics (CFD) simulation is presented to investigate the annular flow behavior in the vertical pipe by using ANSYS Fluent platform 17.2. The study was analyzed complex behavior of annular flow in two cases (upward and downward flow) for different air superficial velocities and range of Reynolds number for water, in order to obtain the effect of orientation flow and increasing superficial gas and liquid velocities on the base film, mean disturbance wave thickness, the average longitudinal size of disturbance wave as well as pressure gradient. For multiphase flow model, the volume of fluid method (VOF) for two-phase flow modelling was used and coupled with RNG k-ε turbulence model to predict fully annular flow structures in the upward and downward flow direction. From CFD simulation results, it is clear to see how increases in air velocity result in reductions in film thickness and increase in pressure gradient. Additionally, the results showed monotonic enhancement of film thickness occurring in tandem with increases in the liquid flow rate. However, due to the effect of gravitational force and interfacial friction, the film thickness and pressure gradient are slightly larger for the upward flow than for the downward flow. The results agree with the recent experimental data that studied the annular flow behavior and pressure drop in the upward and downward flow direction. This study will be very helpful in understanding multiphase flow behavior in natural gas wells.

Towards the practical PLD-IBAD coated conductor fabrication – Long wire, high production rate and Jc enhancement in a magnetic field

2006 ◽  
Vol 445-448 ◽  
pp. 504-508 ◽  
Author(s):  
Yutaka Yamada ◽  
Akira Ibi ◽  
Hiroyuki Fukushima ◽  
Reiji Kuriki ◽  
Seiki Miyata ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Production Rate ◽  
Coated Conductor ◽  
High Production Rate ◽  
High Production
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