1,720,961 research outputs found
Holdup Estimation In Core Flow Using Image Processing
No full textIn this work holdup is estimated through image processing and compared with the value calculated indirectly by the correlation presented by Rodriguez et al. in [1]. The tests were performed in the multiphase-flow test facilities of the Research Centre (CENPES) of PETROBRAS, Brazil. Flow images were obtained with a high-speed video camera at 1000 fps in a 2 7/8-inch and 300 meter deep pilot-scale well, conveying a mixture of heavy crude oil (2000 mPa.s and 950 kg/m3 at 35°C) and water at several combinations of the individual flow rates. In total, four tests were carried out with 100 images each. © 2013 IEEE.334338IEEE Instrumentation and Measurement Society (I and M)Rodriguez, O.M.H., Bannwart, A.C., Experimental study on interfacial waves in vertical core flow (2006) Journal of Petroleum Science and Engineering, 54 (3-4), pp. 140-148. , DOI 10.1016/j.petrol.2006.07.007, PII S0920410506001549Bannwart, A.C., Rodriguez, O.M.H., De Carvalho, C.H.M., Wang, I.S., Vara, R.M.O., Flow patterns in heavy crude oil-water flow (2004) Journal of Energy Resources Technology, 126 (3), p. 184Bannwart, A.C., Modeling aspects of oil-water core-annular flows (2001) Journal of Petroleum Science and Engineering, 32 (2-4), pp. 127-143. , DOI 10.1016/S0920-4105(01)00155-3, PII S0920410501001553, Petroleum Production Research in BrazilBannwart, A.C., Rodriguez, O.M.H., Biazussi, J.L., Martins, F.N., Selli, M.F., De Carvalho, C.H.M., Water-assisted flow of heavy oil in a vertical pipe: Pilot-scale experiments (2011) International Journal of Chemical Reactor Engineering, 10, pp. A32Ghosh, S., Mandal, T.K., Das, G., Das, P.K., Review of oil water core annular flow (2009) Renewable and Sustainable Energy Reviews, 13 (8), pp. 1957-1965. , OctPayne, G.A., Palmer, C.M., Brill, J.P., Beggs, H.D., Evaluation of inclined-pipe, tow-phase liquid holdup and pressure-loss correlations using experimental data (1979) JPT, Journal of Petroleum Technology, 31 (9), pp. 1198-1208Aslina, S., Mazlina, S., Hassan, M.J.W., Ehsan, S.D., In-situ phase fractions for oil and water occupied in pipe (2006) International Journal of Engineering, 3 (2), pp. 248-256Oddie, G., Shi, H., Durlofsky, L.J., Aziz, K., Pfeffer, B., Holmes, J.A., Experimental study of two and three phase flows in large diameter inclined pipes (2003) International Journal of Multiphase Flow, 29 (4), pp. 527-558. , DOI 10.1016/S0301-9322(03)00015-6Strazza, D., Demori, M., Ferrari, V., Poesio, P., Capacitance sensor for hold-up measurement in high-viscous-oil/ conductivewater core-annular flows (2011) Flow Measurement and Instrumentation, 22 (5), pp. 360-369. , OctMenotti, D., Najman, L., Facon, J., De Araujo, A.A., Multi-histogram equalization methods for contrast enhancement and brightness preserving (2007) IEEE Transactions on Consumer Electronics, 53 (3), pp. 1186-1194. , DOI 10.1109/TCE.2007.4341603Chan, T.F., Vese, L.A., Active contours without edges (2001) IEEE Transactions on Image Processing, 10 (2), pp. 266-277. , DOI 10.1109/83.902291Haralick, R.M., Sternberg, S.R., Zhuang, X., Image analysis using mathematical morphology (1987) IEEE Transactions on Pattern Analysis and Machine Intelligence, PAMI-9 (4), pp. 532-55
Interfacial Waves In Stratified Viscous Oil-water Flow
No full textThe analysis of the interfacial wave properties is an important point in understanding of many aspects of separated-flow patterns (annular and stratified). One may cite flow pattern stability, pressure drop and heat transfer as characteristics affected by the wave properties. Previous studies have shown that the phenomenon of flow pattern transition in stratified flow can be related to the interfacial wave structure (problem of hydrodynamic instability). The study of the wavy stratified flow pattern requires the characterization of the interface, i.e., average wave shape, wave speed, amplitude and wavelength as a function of flow properties. Studies on waves in stratified liquid-liquid flow are scanty, even more when related to viscous oils. This article offers new experimental data on interfacial waves collected in a glass test line of 12m and 0.026m i.d., oil (density and viscosity of 854kg/m3 and 0.3Pas at 20°C, respectively) and tap water as the working fluids; the stratified flow was filmed with a high speed video camera at several inclinations from horizontal (-5°, 0°, 5°, 10°). New experimental data and available literature data of interfacial waves in oil-water flow were collected, analyzed and correlated to the flow properties by dimensionless numbers of Reynolds, Froude and Weber. A second-order Fourier series is proposed to model the wave shape. The correlations can be used to predict the average wave geometry and wave speed of typical oil-water interfacial waves within a significant range of superficial velocities and pipe inclinations. Considering the simplicity of the proposed correlation, the agreement between data and predicted wave is encouraging.628598Frisk, D.P., Davis, J., The enhancement of heat transfer by waves in stratified gas-liquid flow (1972) Int. J. Heat Mass Transfer, 15, pp. 1537-1552Wallis, G.B., (1969) One Dimension Two-phase Flow, , McGraw-Hill, New YorkRodriguez, O.M.H., Baldani, L.S., Prediction of pressure gradient and holdup in wavy stratified liquid-liquid pipe flow (2012) J. Petrol. Sci. Eng., pp. 140-151Bontozoglou, V., Hanratty, T.J., Wave height estimation in stratified gas-liquid flows (1989) AIChE J., 35, pp. 1346-1350Bontozoglou, V., Weakly nonlinear Kelvin-Helmholtz waves between fluids of finite depth (1991) Int. J. Multiph. Flow, 17, pp. 509-518Li, G.J., Guo, L., Chen, X.J., An experimental investigation on the interfacial waves in air-water two-phase flow within horizontal pipelines (1997) Chin. J. Chem. Eng., 5, pp. 316-324Tzoti, C., Andritsos, N., Interfacial shear stress in wavy stratified gas-liquid flow in horizontal pipes (2013) Int. J. Multiph. Flow, 54, pp. 43-54Wang, Z.L., Gabriel, K.S., Manz, D.L., The influences of wave height on the interfacial friction in annular gas-liquid flow under normal and microgravity conditions (2004) Int. J. Multiph. Flow, 30, pp. 1193-1211Wang, Z.L., Gabriel, K.S., Zhu, Z.F., The effects of gravity on the features of the interfacial waves in annular two-phase flow (2004) Micrograv. Sci. Technol., 15, pp. 19-27Dyment, A., Boudlal, A., A theoretical model for gas-liquid slug flow in down inclined ducts (2004) Int. J. Multiph. Flow, 30, pp. 512-550Berthelsen, P.A., Ytrehus, T., Calculations of stratified wavy two-phase flow in pipes (2005) Int. J. Multiph. Flow, 31, pp. 571-592Andritsos, N., Hanratty, T.J., Influence of interfacial waves in stratified gas-liquid flows (1987) AIChE J., 33 (3), pp. 444-454Andritsos, N., Hanratty, T.J., Interfacial instabilities for horizontal gas-liquid flows in pipelines (1987) Int. J. Multiph. Flow, 13 (5), pp. 583-603Andritsos, N., Statistical analysis of waves in horizontal gas-liquid flow (1992) Int. J. Multiph. Flow, 18 (3), pp. 465-470Chakrabarti, D.P., Das, G., Ray, S., Pressure drop in liquid-liquid two phase horizontal flow: experiment and prediction (2005) Chem. Eng. Technol., 28 (9), pp. 1003-1009Chakrabarti, D.P., Das, G., Das, P.K., Identification of stratified liquid-liquid flow through horizontal pipes by a non-intrusive optical probe (2007) Chem. Eng. Sci., 62, pp. 1861-1876Charles, M.E., Lilleleht, L.U., An experimental investigation of stability and interfacial waves in co-current flow of two liquids (1965) J. Fluid Mech., 22 (2), pp. 217-224Castro, M.S., Pereira, C.C., Santos, J.N., Rodriguez, O.M.H., Geometrical and kinematic properties of interfacial waves in stratified oil water flow in inclined pipe (2012) Exp. Therm. Fluid Sci., 37, pp. 171-178Sotgia, G., Tartarini, P., Stalio, E., Experimental analysis of flow regimes and pressure drop reduction in oil-water mixtures (2008) Int. J. Multiph. Flow, 34, pp. 1161-1174Yusuf, N., Effect of oil viscosity on the flow structure and pressure gradient in horizontal oil-water flow (2012) Chem. Eng. Res. Des., 90, pp. 1019-1030Brauner, N., Rovinsky, J., Maron, D.M., Determination of the interface curvature in stratified two-phase systems by energy considerations (1996) Int. J. Multiph. Flow, 22, pp. 1167-1185Ng, T.S., Lawrence, C.J., Hewitt, G.F., Interface shapes for two-phase laminar stratified flow in a circular pipe (2001) Int. J. Multiph. Flow, 27, pp. 1301-1311Brauner, N., Maron, D.M., Rovinsky, J., A two-fluid model for stratified flows with curved interfaces (1989) Int. J. Multiph. Flow, 24, pp. 975-1004Raj, T.S., Chakrabarti, D.P., Das, G., Liquid-liquid stratified flow through horizontal conduits (2005) Chem. Eng. Technol., 28, pp. 899-907Taitel, Y., Dukler, A.E., A model for predicting flow regime transitions in horizontal and near horizontal gas-liquid flows (1976) AIChE J., 22, pp. 47-55Trallero, J.L., (1995), Oil-water Flow Patterns in Horizontal Pipes, Dissertation, University of Tulsa, TulsaTrallero, J.L., Sarica, C., Brill, J.P., A study of oil/water flow patterns in horizontal pipes (1997) SPE Prod. Facil., 12, pp. 165-172Elseth, G., An Experimental Study of Oil-water Flow in Horizontal Pipes (2001), Dissertation, Norwegian University of Science and Technology, TrodheimAlkaya, B., Jayawardena, S.S., Brill, J.P., Oil-water flow patterns in slightly inclined pipes (2000), pp. 14-17. , Proceeding of ETCE/OMAE2000 International Conference of Energy for the New Millennium, New Orleans, ASME, New YorkBannwart, A.C., Flow patterns in heavy crude oil-water flow (2004) J. Energy Resour. Technol., 126, pp. 184-189Ardron, K.H., One-dimensional two-fluid equations for horizontal stratified two-phase flow (1980) Int. J. Multiph. Flow, 6, pp. 295-304Jones, A.V., Prosperetti, A., On the suitability of first-order differential models for two-phase flow prediction (1985) Int. J. Multiph. Flow, 11, pp. 133-148Jones, A.V., Prosperetti, A., The linear stability of general two-phase flow models - II (1987) Int. J. Multiph. Flow, 13, pp. 161-171Song, J.H., Ishii, M., On the stability of a one-dimensional two-fluid model (2001) Nucl. Eng. Des., 204, pp. 101-115Brauner, N., Two-phase liquid-liquid annular flow (1991) Int. J. Multiph. Flow, 17, pp. 59-76Brauner, N., Maron, D.M., Stability analysis of stratified liquid-liquid flow (1992) Int. J. Multiph. Flow, 18, pp. 103-121Brauner, N., Maron, D.M., Flow pattern transitions in two-phase liquid-liquid flow in horizontal tubes (1992) Int. J. Multiph. Flow, 18, pp. 123-140Rodriguez, O.M.H., Oliemans, R.V.A., Mude, R.F., Stability analysis of slightly-inclined stratified oil-water flow, including the distribution coefficients and the cross-section curvature (2006) Proceedings of 5th North American Conference Multiphase Technol, pp. 229-245. , BanffRodriguez, O.M.H., Banwart, A.C., Stability analysis of core-annular flow and neutral stability wave number (2008) AIChE J., 54, pp. 20-31Crowley, C.J., Wallis, G.B., Barry, J.J., Validation of a one-dimensional wave model for the stratified-to-slug flow regime transition, with consequences for wave growth and slug frequency (1992) Int. J. Multiph. Flow, 18, pp. 249-271Ooms, G., The hydrodynamic stability of core-annular flow of two ideal liquid (1972) Appl. Sci. Res.Ooms, G., Seagal, A., Van Der Wees, A.J., Meerhoff, R., Oliemans, R.V.A., A theoretical model for core annular flow of a very viscous oil core and a water annulus through a horizontal pipe (1984) Int. J. Multiph. Flow, 10, pp. 41-60Oliemans, R.V.A., (1986), The Lubricating-film Model for Core-annular Flow, Dissertation, Technische Hogeschool Delft, Delft University, DelftFeng, Huang, P.Y., Joseph, D.D., Dynamic simulation of the motion of capsules in pipelines (1995) J. Fluid Mech., 286, pp. 201-227Huang, A., Joseph, D.D., Stability of eccentric core annular flow (1995) J. Fluid Mech., 282, pp. 233-245Hu, H.H., Patankar, N., Non-axisymmetric instability of core-annular flow (1995) J. Fluid Mech., 290, pp. 213-224Bai, Kelkar, K., Joseph, D.D., Direct simulation of interfacial waves in a high viscosity ratio and axisymmetric core annular flow (1996) J. Fluid Mech., 32, pp. 1-34Bai, R., Joseph, D.D., Steady flow and interfacial shapes of a highly viscous dispersed phase (2000) Int. J. Multiph. Flow, 26, pp. 1469-1491Rodriguez, O.M.H., Banwart, A.C., Experimental study on interfacial waves in vertical core flow (2006) J. Petrol. Sci. Eng., 54, pp. 140-148Rodriguez, O.M.H., Castro, M.S., Interfacial-tension-force model for the wavy-stratified liquid-liquid flow pattern transition (2014) Int. J. Multiph. Flow, 58, pp. 114-126Al-Wahaibi, T., Angeli, P., Transition between stratified and non-stratified horizontal oil-water flows. Part I: stability analysis (2007) Chem. Eng. Sci., 62, pp. 2915-2928Al-Wahaibi, T., Smith, M., Angeli, P., Transition between stratified and non-stratified horizontal oil-water flows. Part II: mechanism of drop formation (2007) Chem. Eng. Sci., 62, pp. 2929-2940Al-Wahaibi, T., Angeli, P., Experimental study on interfacial waves in stratified horizontal oil-water flow (2011) Int. J. Multiph. Flow, 37, pp. 930-940Barral, A.H., Angeli, P., Interfacial characteristics of stratified liquid-liquid flows using a conductance probe (2013) Exp. Fluids, 54 (1604)Rodriguez, I.H., Yamaguti, H.K.B., Castro, M.S., Da Silva, M.J., Rodriguez, O.M.H., Slip ratio in dispersed viscous oil-water pipe flow (2011) Exp. Therm. Fluid Sci., 35, pp. 11-19Bendat, J.S., Piersol, A.G., (2000) Random Data: Analysis and Measurement Procedures, , John Wiley & Sons, New YorkAl-Sarkhi, A., Sarica, C., Magrini, K., Inclination effects on wave characteristics in anular gas-liquid flows (2012) AIChE J., 58 (4), pp. 1018-1029Arney, M.S., Bai, R., Guevara, E., Joseph, D.D., Liu, K., Friction factor and holdup studies for lubricated pipeling - I (1993) Int. J. Multiph. Flow, 19 (6), pp. 1061-1076Rodriguez, O.M.H., Castro, M.S., Interfacial-tension-force model for the wavy-stratified liquid-liquid flow pattern transition (2014) Int. J. Multiph. Flow, 58, pp. 114-126Barnea, D., Taitel, Y., Non-linear interfacial instability of separated flows (1994) Chem. Eng. Sci., 49, pp. 2341-2349Salhi, Y., Si-Ahmed, E., Legrand, J., Degrez, G., Stability analysis of inclined stratified two-phase gas-liquid flow (2010) Nucl. Eng. Des., 240, pp. 1083-1086Banner, M.L., Melville, W.K., On the separation of air flow over water waves (1976) J. Fluid Mech., 77, pp. 825-84
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Pressure Drop In Water-assisted Three-phase Flow Of Heavy Oil And Gas In A Vertical Pipe
No full textThis paper presents measurements of pressure drop for three-phase water-assisted flow of heavy crude oil, water and air at several flow rates inside a 2.84 cm i.d. vertical glass pipe, at pressure and temperature close to ambient. The superficial velocities used in the tests ranged from 0.02 to 1.2 m/s for oil, 0.04 to 0.5 m/s for water and 0.04 to 9.0 m/s for air. The oil was crude dead oil with a viscosity of 5,040 mPa.s and a density of 971 kg/m 3 at 25°C. A representative physical model is proposed to interpret the experimental data gathered. © BHR Group 2006 Multiphase Technology 5.2006421433Tissot, B.P., Weite, D.H., (1984) Petroleum Formation and Occurrence, Second Edition, , Springer-Verlag, New YorkBriggs, P.J., Baron, R.P., Fulleylove, R.J., Wright, M.S., (1988) Development of Heavy - Oil Reservoirs, pp. 206-214. , SPE 15748Wehunt, C.D., Burke, N.E., Noonan, S.G., Bard, T.R., (2003) Technical Challenges for Offshore Heavy Oil Field Developments, , paper OTC 15281Pinto, A.C.C., Offshore heavy oil in Campos basin: The Petrobras experience (2003) 2003 Offshore Technology Conference, , Houston, May 5-8, paper SPE 15283Vanegas-Prada, J.W.V., (1999) Experimental Study of Annular Oil-water Flow (Core Flow) in Elevation of Ultra Viscous Oils (in Portuguese), , MSc. thesis, Department of Petroleum Engineering, State University of Campinas, FEM-UNICAMP, Campinas-SP, BrazilOoms, G., Segal, A., Van Der Wees, A.J., Meerhoff, R., Oliemans, R.V.A., A theoretical model of core annular flow of very viscous oil core and a water annulus through a horizontal pipe (1984) Int. J. Mult. Flow, 10, pp. 41-60Bannwart, A.C., Rodriguez, O.H.M., Carvalho, C.H.M., Wang, I.S., Vara, R.M., Flow patterns in heavy crude oil-water flow (2004) J. En. Res. Tech. ASME, 126, pp. 184-189Bannwart, A.C., Rodriguez, O.M.H., Trevisan, F.E., Vieira, F.F., Carvalho, C.H.M., Flow patterns and pressure gradient in horizontal, upward inclined and vertical heavy oil-water and heavy oil-water-gas flows: Experimental investigation and full-scale experiments (2004) Proc. 3 rd International Symposium on Multiphase Flow Modeling and Experimentation, 4, pp. 2605-2613. , Pisa, Italy, September 22-25Bannwart, A.C., Vieira, F.F., Carvalho, C.H.M., Oliveira, A.P., Water-assisted flow of heavy oil and gas in a vertical pipe (2005) 2005 SPE International Thermal Operations and Heavy Oil Symposium, , Calgary, Alberta, Canada, November 1-3, paper SPE-97875-PPZuber, N., Findlay, J.A., Average volumetric concentration in two-phase flow systems (1965) J. Heat Transfer ASME - Series C, 87, pp. 453-46
A High Spatial And Temporal Resolution Film Thickness Sensor In Oil - Water Flows
No full textThis work presents a study of a new technique for non-intrusive measurement of liquid-liquid flow. The evaluated film thickness sensor has 64 × 16 measuring points and a measuring area of 128 × 32 mm. This sensor measures the electrical conductance and, through a calibration procedure, converts those signals in water film thickness. The experimental work was carried out in the Swiss Federal Institute of Technology Zurich (ETHZ) in Zurich, Switzerland. © 2014 IEEE.5761 IEEE Instrumentation and Measurement Society (I and M)Clark, W.W., Liquid film thickness measurement (2002) Multiphase Science and Technology, 14 (1), pp. 1-74Tibiriçá, C.B., Do Nascimento, F.J., Ribatski, G., Film thickness measurement techniques applied to micro-scale two-phase flow systems (2010) Experimental Thermal and Fluid Science, 34 (4), pp. 463-473. , MayAlekseenko, S.V., Cherdantsev, A.V., Kharlamov, S.M., Markovich, D.M., Secondary instability of waves in annular two-phase flow with and without entrainment (2010) Journal of Physics: Conference Series, 216, p. 012006. , MarDamsohn, M., Prasser, H., High-speed liquid film sensor for two-phase flows with high spatial resolution based on electrical conductance (2009) Flow Measurement and Instrumentation, 20 (1), pp. 1-14. , MarThiele, S., Da Silva, M.J., Hampel, U., Capacitance planar array sensor for fast multiphase flow imaging (2009) IEEE Sensors Journal, 9 (5), pp. 533-540. , MaySilva, M.J.D., Schleicher, E., Hampel, U., Capacitance wire-mesh sensor for fast measurement of phase fraction distributions (2007) Measurement Science and Technology, 18 (7), pp. 2245-2251. , JulIto, D., Damsohn, M., Prasser, H.-M., Aritomi, M., Dynamic film thickness between bubbles and wall in a narrow channel (2011) Experiments in Fluids, 51 (3), pp. 821-833. , MayDamsohn, M., Prasser, H.M., High-speed liquid film sensor with high spatial resolution (2009) Measurement Science and Technology, 20 (11), p. 114001. , NovPrasser, H., A new electrode-mesh tomograph for gas-liquid flows (1998) Flow Measurement and Instrumentation, 9 (2), pp. 111-119. , JunBonilla Riano, A., Bannwart, A.C., Rodriguez, O.M.H., Holdup estimation in core flow using image processing (2013) IEEE Instrumentation and Measurement Technology Conference, pp. 334-338. , art. no. 6555435 Ma
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
