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1
Content available Evaluation of liquid-gas flow in pipeline using gamma-ray absorption technique and advanced signal processing
Hanus Robert, Zych Marcin, Mosorov Volodymyr, Golijanek-Jędrzejczyk Anna, Jaszczur Marek, Andruszkiewicz Artur
Metrology and Measurement Systems
|
2021
|
Vol. 28, nr 1
145--159
EN
Liquid-gas flows in pipelines appear in many industrial processes, e.g. in the nuclear, mining, and oil industry. The gamma-absorption technique is one of the methods that can be successfully applied to study such flows. This paper presents the use of the gamma-absorption method to determine the water-air flow parameters in a horizontal pipeline. Three flow types were studied in this work: plug, transitional plug-bubble, and bubble one. In the research, a radiometric set consisting of two Am-241 sources and two NaI(TI) scintillation detectors have been applied. Based on the analysis of the signals from both scintillation detectors, the gas phase velocity was calculated using the cross-correlation method (CCM). The signal from one detector was used to determine the void fraction and to recognise the flow regime. In the latter case, a Multi-Layer Perceptron-type artificial neural network (ANN) was applied. To reduce the number of signal features, the principal component analysis (PCA) was used. The expanded uncertainties of gas velocity and void fraction obtained for the flow types studied in this paper did not exceed 4.3% and 7.4% respectively. All three types of analyzed flows were recognised with 100% accuracy. Results of the experiments confirm the usefulness of the gamma-ray absorption method in combination with radiometric signal analysis by CCM and ANN with PCA for comprehensive analysis of liquid-gas flow in the pipeline.
2
Content available Design and simulation of a multienergy gamma ray absorptiometry system for multiphase flow metering with accurate void fraction and water-liquid ratio approximation
Khayat Omid, Afarideh Hossein
Nukleonika
|
2019
|
Vol. 64, No. 1
19--29
EN
Multiphase flow meters are used to measure the water-liquid ratio (WLR) and void fraction in a multiphase fluid stream pipeline. In the present study, a system of multiphase flow measurement has been designed by application of three thallium-doped sodium iodide scintillators and a radioactive source of 133Ba simulated by Monte Carlo N-particle (MCNP) transport code. In order to capture radiations passing across the pipe, two direct detectors have been installed on opposite sides of the radioactive source. Another detector has been placed perpendicular to the transmission beam emitted from the 133Ba source to receive radiations scattered from the fluid flow. Simulation was done by the MCNP code for different volumetric fractions of water, oil, and gas phases for two types of flow regimes, namely, homogeneous and annular; training and validation data have been provided for the artificial neural network (ANN) to develop a computation model for pattern recognition. Depending on applications of the neural system, several structures of ANNs are used in the current paper to model the flow measurement relations, while the detector outputs are considered as the input parameters of the neural networks. The first, second, and third structures benefit from two, three, and five multilayer perceptron neural networks, respectively. Increasing the number of ANNs makes the system more complicated and decreases the available data; however, it increases the accuracy of estimation of WLR and gas void fraction. According to the results, the maximum relative difference was observed in the scattering detector. It was clear that transmission detectors would demonstrate the difference between the flow regimes as well. It is necessary to note that the error calculated by the MCNP simulator is <0.5% for the direct detectors (TR1 and TR2). Due to the difference between the data of the two flow regimes and the errors of data in the simulation codes of the MCNP, it was possible to separate these flow regimes. The effect of changing WLR on the efficiency for a constant void fraction confi rms a considerable variance in the results of annular and homogeneous flow s occurring in the scattering detector. There is a similar trend for the void fraction; hence, one can easily distinguish changes in efficiency due to the WLR. Analysis of the simulation results revealed that in the proposed structure of the multiphase flow meter and the computation model used for simulation, the two flow regimes are simply distinguishable.
3
Content available Designing a simple radiometric system to predict void fraction percentage independent of flow pattern using radial basis function
Roshani G. H., Nazemi E., Shama F., Imani M. A., Mohammadi S.
Metrology and Measurement Systems
|
2018
|
Vol. 25, nr 2
347--358
EN
The void fraction is one of the most important parameters characterizing a multiphase flow. The prediction of the performance of any system operating with more than single phase relies on our knowledge and ability to measure the void fraction. In this work, a validated simulation study was performed in order to predict the void fraction independent of the flow pattern in gas-liquid two-phase flows using a gamma ray 60Co source and just one scintillation detector with the help of an artificial neural network (ANN) model of radial basis function (RBF). Three used inputs of ANN include a registered count under Compton continuum and counts under full energy peaks of 1173 and 1333 keV. The output is a void fraction percentage. Applying this methodology, the percentage of void fraction independent of the flow pattern of a gas-liquid two-phase flow was estimated with a mean relative error less than 1.17%. Although the error obtained in this study is almost close to those obtained in other similar works, only one detector was used, while in the previous studies at least two detectors were employed. Advantages of using fewer detectors are: cost reduction and system simplification.
4
Content available remote Badania przepływu ciecz-gaz w rurociągu metodą absorpcji promieniowania gamma
Hanus R., Zych M., Petryka L.
Przegląd Elektrotechniczny
|
2017
|
R. 93, nr 9
97--100
PL
Artykuł omawia zastosowanie metody absorpcji promieniowania gamma do wyznaczania parametrów przepływu ciecz-gaz w rurociągu poziomym. Sygnały z zestawu radiometrycznego wykorzystano do wyznaczania prędkości fazy rozproszonej, współczynnika wypełnienia oraz identyfikacji struktury przepływu. Przedstawiono przykładowe wyniki badań przeprowadzonych na stanowisku laboratoryjnym wyposażonym w zamknięte źródła promieniowania 241Am i sondy scyntylacyjne z kryształami NaI(Tl).
EN
The article presents application of the gamma-ray absorption method to determine the parameters of the liquid-gas flow in a horizontal pipeline. The signals from radiometric set were used for determining the velocity of the dispersed phase, void fraction and identification of flow structure. Results of experiments carried out on a laboratory stand equipped with sealed gamma-ray sources 241Am and scintillation probes with NaI(Tl) crystals are presented.
5
Content available Udział objętościowy faz w mieszaninie dwufazowej gaz-ciecz przepływającej przez kanał wypełniony pianą metalową
Płaczek M., Dyga R., Witczak S.
Inżynieria i Aparatura Chemiczna
|
2015
|
Nr 6
348--349
PL
Przedstawiono wyniki badań doświadczalnych udziału objętościowego gazu w przepływie dwufazowym powietrze-woda oraz powietrze-olej przez poziomy kanał wypełniony pianą aluminiową. Zbadano trzy piany o gęstości upakowania porów 20, 30 i 40 PPI. Zmiany wartości udziałów objętościowych powiązano ze strukturami prze pływu. Wyniki badań wskazują na brak istotnego wpływu parametrów strukturalnych piany metalowej na wartość udziału objętościowego faz.
EN
The paper presents the experimental results of gas void fraction in air-water and oil-water two-phase flow through a horizontal channel filled with aluminum metal foam. Three metal foams with the pore density equal to 20, 30 and 40 PPI were examined. A change of void fraction values in given flow conditions was coupled with flow patterns. The research results indicate that there is no significant effect of metal foam structural parameters on void fraction.
6
Content available Ocena metod wyznaczania udziałów objętościowych faz w odniesieniu do przepływu gaz-ciecz w kanałach wypełnionych pianami metalowymi
Płaczek M., Dyga R.
Inżynieria i Aparatura Chemiczna
|
2015
|
Nr 6
346--347
PL
Przedstawiono wyniki badań udziału objętościowego gazu w przepływie powietrze-olej przez poziomy kanał wypełniony pianą aluminiową (20, 30 i 40 PPI). Ocena statystyczna metod obliczeniowych opracowanych dla ośrodków porowatych wykazała, że nie pozwalają one przewidywać wartości udziałów objętościowych faz w przepływie przez kanały wypełnione pianą z zadowalającą dokładnością. Ocena modeli opracowanych dla przepływów przez kanały niewypełnione wykazała, że najlepszą zgodność danych eksperymentalnych z obliczonymi otrzymano wykorzystując modele GE RAMP oraz Zubera-Findlaya.
EN
Experimental results of gas void fraction in air – oil two-phase flow through a horizontal channel filled with aluminum metal foam (20, 30 and 40 PPI) are presented in the paper. A statistical evaluation of methods used for the calculation of gas void fraction in porous media indicated incapability of predicting such values in foam packing channels with acceptable accuracy. The evaluation of models developed for the flow through channels without packing showed that the best agreement between experimental and calculated gas void fraction values was obtained using the GE RAMP and Zuber-Findlay models.
7
Content available Pomiar lokalnego stopnia zapełnienia, stopnia suchości oraz współczynnika przejmowania ciepła w prostokątnym minikanale asymetrycznie ogrzewanym
Kaniowski R.
Pomiary Automatyka Kontrola
|
2013
|
R. 59, nr 5
477--480
PL
W artykule omówiono technikę jednoczesnego pomiaru stopnia zapełnienia przy wrzeniu w przepływie i rozkładu temperatury powierzchni grzejnej. Przedmiotem badań było rozpoznanie struktur przepływu dwufazowego, stopnia zapełnienia i stopnia suchości oraz zmiennych wraz z nimi współczynników przejmowania ciepła przy wrzeniu w przepływie płynu przez pionowy, prostokątny minikanał.
EN
Heat transfer to boiling liquid flowing through narrow minichannels has become a modern solution to heat transfer enhancement in small, mainly electronic devices. The paper discusses the method for simultaneous measurement of the flow boiling void fraction and heating surface temperature distribution, which aims at determining local values of the vapor quality and heat transfer coefficients. The studies were conducted for boiling FC-72 in a rectangular, vertical and asymmetrically heated minichannel. Employing a high-speed camera on the measurement stand constructed by the author helped to determine, for the set sections, the void and liquid fractions as a function of variable thermal and flow parameters such as channel hydraulic diameter, heat flux, pressure, mass flux and temperature of liquid subcooling at the minichannel inlet. Measurements of the heating surface temperature distribution and photographic observations of the two-phase flows, when conducted simultaneously, allow deter-mining the dependence of the recorded local void fraction on the local temperature. The liquid crystal thermography technique helped to perform the repetitious measurements of the temperature on the heating surface. One of the advantages of this technique is a possibility of observing the instantaneous temperature field of the heating surface. There were observed the following flow patterns: bubbly flow, bubbly-slug flow, slug flow, slug-wispy flow and wispy flow.
8
Content available Determination of the temperature field using liquid crystal thermography and analysis of two-phase flow structures in research on boiling heat transfer in a minichannel
Piasecka M.
Metrology and Measurement Systems
|
2013
|
Vol. 20, nr 2
205--216
EN
The paper presents the application of liquid crystal thermography for temperature determination and visualisation of two phase flow images on the studied surface. Properties and applications of thermochromic liquid crystals are discussed. Liquid crystals were applied for two-dimensional detection of the temperature of the heating foil forming one of the surfaces of the minichannel along which the cooling liquid flowed. The heat flux supplied to the heating surface was altered in the investigation and it was accompanied by a change in the color distribution on the surface. The accuracy of temperature measurements on the surface with liquid crystal thermography is estimated. The method of visualisation of two-phase flow structures is described. The analysis of monochrome images of flow structures was employed to calculate the void fraction for some cross-sections. The flow structure photos were processed using Corel graphics software and binarized. The analysis of phase volumes employed Techsystem Globe software. The measurement error of void fraction is estimated.
9
Content available Measurements of two-phase flow patterns and local void fraction in vertical rectangular minichannel
Kaniowski R., Poniewski M.
Archives of Thermodynamics
|
2013
|
Vol. 34, no. 2
3--21
EN
Technology advancements entail a necessity to remove huge amounts of heat produced by today’s electronic devices based on highly integrated circuits, major generators of heat. Heat transfer to boiling liquid flowing through narrow minichannels is a modern solution to the problem of heat transfer enhancement. The study was conducted for FC-72 boiling in a rectangular, vertical and asymmetrically heated minichannel that had depths of 0.5–1.5 mm, a width of 20 mm and a length of 360 mm. The heat flux increased and decreased within the range of 58.3–132.0 kWm-2, the absolute pressure ranged from 0.116 to 0.184 MPa and the mass flux was 185–1139.2 kgm-2s-1. The boiling process took place on a flat vertical heating surface made of Haynes-230 0.1 mm thick acid-proof rolled plate with the surface roughness of 121 μm.
10
Content available Void fraction and flow regime determination by means of MCNP code and neural network
Rabiei A., Shamsaei M., Kafaee M., Shafaei M., Mahdavi N.
Nukleonika
|
2012
|
Vol. 57, No. 3
345-349
EN
One of the non-intrusive and accurate methods of measuring void fraction in two-phase gas liquid pipe flows is the use of the gamma-transmission void fraction measurement technique. The goal of this study is to describe low-energy gamma-ray densitometry using an 241Am source for the determination of void fraction and flow regime in water/gas pipes. The MCNP code was utilized to simulate electron and photon transport through materials with various geometries. Then, a neural network was used to convert multi-beam gamma-ray spectra into a classification of the flow regime and void fraction. The simulations cover the full range of void fraction with Bubbly, Annular and Droplet flows. By using simulation data as input to the neural networks, the void fraction was determined with an error less than 3% regardless of the flow regime. It has thus been shown that multi-beam gamma-ray densitometers with a detector response examined by neural networks can analyze a two-phase flow with high accuracy.
11
Content available Wpływ wypełnienia porowatego na wymianę ciepła oraz hydrodynamikę przepływu gaz-ciecz przez metale komórkowe
Dyga R., Witczak S.
Inżynieria i Aparatura Chemiczna
|
2012
|
Nr 6
314-315
PL
Przedstawiono analizę wyników badań doświadczalnych dotyczących wymiany cicpla oraz hydrodynamiki przepływu dwufazowego gaz - ciecz przez kanał wypełniony pianą aluminiową. Stwierdzono, że zarówno z punktu widzenia wymiany ciepła jak i hydrodynamiki przepływu, dominującą rolę w przepływie odgrywa ciecz. Zwraca uwagę fakt, że obecność piany aluminiowej nie powoduje rozproszenia płynów, a kształtujące się struktury przepływu odpowiadają strukturom w kanałach niewypełnionych.
EN
Analysis of experimental results dealing with heat exchange and hydrodynamics of two-phase gas-liquid flow through a channel filled with aluminium foam is presented. It was found that from heat transfer and flow hydrodynamics point of view liquid plays predominant role. It is also worth noting that the presence of aluminium foam does not cause fluid dispersion and the formed flow structures correspond to those occurring in unfilled channels.
12
Content available Experimental investigations into the impact of the void fraction on the condensation characteristics of R134a refrigerant in minichannels under conditions of periodic instability
Kuczyński W., Charun H.
Archives of Thermodynamics
|
2011
|
Vol. 32, no. 2
21-37
EN
This paper present the results of experimental investigations of condensation of R134a refrigerant in pipe minichannels with internal diameters 0.64, 0.90, 1.40, 1.44, 1.92 and 3.30 mm subject to periodic pressure instabilities. It was established that as in conventional channels, the displacement velocity of the pressure instabilities distinctly depends on the frequency of their hydrodynamic generation. The void fraction distinctly influences the velocity of the pressure instabilities. The form of this relationship depends on the internal diameter of the minichannels and on the method of calculating the void fraction.
13
Content available remote Capacitance sensor for void fraction measurement
Krupa A., Jaworek A.
Przegląd Elektrotechniczny
|
2010
|
R. 86, nr 7
196-198
PL
Wyznaczono charakterystyki pomiarowe przetwornika pojemnościowego do pomiaru stopnia zapełnienia w przepływach dwufazowych o strukturze korkowej, pierścieniowej i pęcherzowej. Przetwornik pojemnościowy składa się z dwóch elektrod umieszczonych na zewnętrznej ściance rury. Zmiany pojemności przetwornika spowodowane zmianą zawartości faz w przepływie mierzone są w obwodzie rezonansowym generatora w.cz. Zmiany częstotliwości generatora są miarą zawartości fazy gazowej w rurze.
EN
Characteristics of capacitance sensor used for void fraction measurements in two phase flow of slug, annular or bubble flows patterns have been determined. The sensor consists of two electrodes mounted on outer side of the pipeline. The capacitance changes due to void fraction variations were measured in a radio-frequency resonant circuit. The frequency deviations are the measure of void fraction in the pipeline.
14
Content available Wpływ ciśnienia na hydrodynamikę przepływu mieszaniny dwufazowej ciecz - gaz w minikanale
Sowiński J., Fidos H.
Inżynieria i Aparatura Chemiczna
|
2010
|
Nr 4
72-73
PL
W pracy zbadano wpływ ciśnienia panującego podczas przepływu mieszanina dwufazowej ciecz - gaz w minikanale na wartości wyznaczanych udziałów faz. Ciśnienia w minikanale zmieniano poprzez zwiększanie ciśnienia hydrostatycznego na jego wylocie. W wyniku przeprowadzonych badań stwierdzono, istotny wpływ wielkości ciśnienia w minikanale na rejestrowane wartości udziału faz oraz na wielkości i kształty przepływających w mieszaninie dwufazowej pęcherzy gazowych.
EN
The aim of this study was to investigate an influence of pressure during flow of two-phase gas - liquid mixture in a mini-channel on values of determined phase fractures. Pressure in the mini-channel was changed by increasing hydrostatic pressure at the outlet. As a result of investigations it was found the significant influence of pressure in the minichannel on recorded values of phase fracture, size and shape of gas bubbles in two-phase mixture.
15
Content available Ocena metod obliczania udziałów objętościowych faz we wznoszącym przepływie trójfazowym
Płaczek M., Witczak S.
Inżynieria i Aparatura Chemiczna
|
2010
|
Nr 2
97-98
PL
Przedstawiono metody wyznaczania współczynnika przejmowania ciepła przy wrzeniu w przepływie płynu chłodniczego w minikanale. Zastosowana technika termografli ciekłokrystalicznej pozwala określić wystąpienie inicjacji wrzenia. Zagadnienie rozwiązywane jest za pomocą funkcji Trefftza, którymi aproksymuje się nieznane temperatury. Ponadto funkcje Trefftza służą do tworzenia funkcji bazowych w metodzie elementów skończonych (MEST). Porównano wyniki otrzymane przy wykorzystaniu obu metod.
EN
Results of research of three-phase air - water - oil flow in vertical pipes are presented in the paper. The limitations and possibilities of using two- and three-phase flow calculating methods available in literature to predicting void fractions in three-phase flow are described. The analysis and evaluation of accuracy of these models confirmed that the drift-flux model was the most advantageous. A new model-based method for void fractions calculations in three-phase upflow is presented.
16
Content available remote Local void fraction and liquid turbulence measurements of two-phase flow downstream of a sudden expansion
Ahmed W. H., Ching C. Y., Shoukri M.
Transactions of the Institute of Fluid-Flow Machinery
|
2006
|
nr 118
3-14
EN
The flow structure of horizontal air-oil two-phase flow downstream of a sudden area expansion has been experimentally investigated using hot-folm anemometry. The time averaged local profiles of the void fraction, mean liquid velocity and the liquid turbulence intensity for elongated bubble flow downstream of the expansion are presented in this paper. The development of the flow pattern downstream of the expansion was investigated using dorect observations of the flow using a high speed video camera. The sudden expansion was found to have a strong effect on the phase redistribution immediately downstream of the expansion. However, the "fully developed" flow regime and void fraction are found to be dependent only on the downstream flow parameters.
17
Udziały objętościowe faz w przepływie trójfazowym powietrze - woda - olej w rurach pionowych
Nowak M., Troniewski L., Witczak S.
Inżynieria i Aparatura Chemiczna
|
2006
|
Nr 6s
168-169
EN
An attempt to connect the gas void fraction with flow patterns in three-phase air - water - oil flow was undertaken in the paper. A comparison of the measured and calculated gas void fractions for several models were described. The best agreement between the measured and calculated gas void fractions were obtained for strongly dispersed water - oil flow.
18
Content available remote Hydrodynamics of the gas-liquid flow in the pipe bend
Witczak S., Pietrzak M.
Archives of Thermodynamics
|
2006
|
Vol. 27, no. 4
227-234
EN
This paper presents two phase air-oil flow in pipe bend with tube inside diameter D = 0.016 m, curvature radius R = 0.11 in and angle 0 = 180[degrees]. The mixture of gas-liquid flowed upwards and downwards across the bend. In the paper upflow and downflow in pipe bend are compared. As a result, flow patterns formed in pipe bend are determined as well as determined void fractions of gas phase.
19
Określenie udziału objętościowego metodami stereologicznymi
Masiukiewicz M.
Zeszyty Naukowe. Mechanika / Politechnika Opolska
|
2005
|
z. 80
103-111
PL
W prezentowanej pracy przedstawiono metodę identyfikacji struktury opartą na analizie obrazu metodami stereologicznymi. Tak opracowany system pomiarowy umożliwia dokonanie oceny zmian struktury mieszaniny dwufazowej zachodzących w czasie na podstawie wybranej grupy stereologicznych parametrów struktury. Cała analiza dokonywana jest na sekwencjach filmowych zarejestrowanych cyfrową kamerą do zdjęć szybkich.
EN
Pattern identification method, based on image analysis with stereological techniques, is presented in this paper. Developed measurement method allows estimation of changes of two phase mixture flow pattern in time. The measurements are taken on selected group of stereological parameters of the pattern. The analysis is done on movie clips of investigated process. Recorded images are taken with the use of high speed CCD camera.
20
A new model of bubble - liquid interaction in the boundary layer
Mikielewicz D.
Zeszyty Naukowe Politechniki Świętokrzyskiej. Mechanika
|
1999
|
Z. 67
283--292
EN
In the present work a new approach to modelling of the void fraction in the upward flow in the boundary layer is presented. The circulation around the bubble is modified to what has been previously assumed in the literature. The circulation is composed of two mechanisms which rotate in opposite directions. The resulting model predicts the wall peaking as well as the core peaking depending primarily on the bubble diameter. The proposed mechanism is entirely new in the available approaches. It is relatively general and enables future modifications.
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