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Sthener R V Campos - One of the best experts on this subject based on the ideXlab platform.
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orifice plate meter field performance formulation and validation in multiphase flow conditions
2014Co-Authors: Sthener R V Campos, Jorge Luis Balino, Ivan Slobodcicov, Durval Florencio FilhoAbstract:Abstract The performance of orifice plates in real-time monitoring of oil, gas and water standard flow rates was investigated. To this end, a multi-rate test was implemented in two production wells routed individually to a test separator in field operational conditions. The well flow rate was varied in steps by changing the choke opening. The ranges of fluid properties and flow conditions achieved during the experiment were: wellhead pressure from 9073 kPa to 13,278 kPa, wellhead temperature from 47.8 °C to 53.5 °C, downstream choke pressure from 6770 kPa to 7913 kPa, downstream choke temperature from 41.6 °C to 49.1 °C, gas–oil-ratio from 1144 Sm 3 / Sm 3 to 2068 Sm 3 / Sm 3 , water-cut from 4.64% to 58.35%, standard oil specific gravity from 0.7988 to 0.8058, standard gas specific gravity from 0.7340 to 0.7550, standard oil flow rate from 46.86 Sm 3 / d to 266.65 Sm 3 / d , standard gas flow rate from 62.68 × 10 3 Sm 3 / d to 296.65 × 10 3 Sm 3 / d , standard water flow rate from 18.06 m 3 / d to 159.33 m 3 / d . The wells tested showed a different dynamic behavior: while well #2 did not vary significantly the stream composition with flow rate, well #1 produced under gas coning, a near well-reservoir phenomenon that governs the contribution of the reservoir gas-cap to the total stream composition. The multi-rate tests generated two data sets with 1424 flow conditions through two flange-tap orifice plates installed upstream (wellhead) and downstream of a cage choke valve. The ranges of orifice variables were: orifice diameter from 0.03479 m to 0.0430 m, beta factor from 0.4946 to 0.6507, differential pressure from 15 kPa to 187 kPa. The virtual metering system presented in Paz et al. (2010) was used to correlate the experimental data. The associated model, suitable for differential pressure measuring devices, includes effects such as flow concentration and slip (through Chisholm’s correlation), generalizing the mass flow rate versus pressure drop relationship for multiphase flow. The total mass flow rate depends on a set of variables evaluated at metering conditions: density and viscosity of the liquid and gas phase, mass quality, pressure drop across the flow meter and geometry (contraction area and beta factor). The determination of the fluid properties at metering conditions was made by using black-oil correlations. These correlations are based on a set of input variables at standard condition that characterizes the stream composition such as gas–oil ratio, water–oil ratio and specific gravities of each phase. A comparison was made between the multiphase flow rates predicted by the model and the ones simultaneously measured at the test separators. The oil, gas and water standard volumetric flow rate deviations (coefficients of variation of the root mean square deviations) were below 3.52 % . It was theoretically demonstrated and experimentally verified that a systematic error exists when the homogeneous model (equal phase velocities) is considered in the formulation, resulting in a flow rate underestimation. When the homogeneous model was used to correlate the data, this effect increased the deviation up to 10.5 % . Flow pattern at the wellhead was characterized as intermittent and annular-mist. Lockhart–Martinelli Parameter varied from 0.362 to 0.836; despite of the experimental data being beyond the wet gas region, the multi-rate tests showed that Chisholm’s over-reading can be successfully extrapolated to these range.
Durval Florencio Filho - One of the best experts on this subject based on the ideXlab platform.
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orifice plate meter field performance formulation and validation in multiphase flow conditions
2014Co-Authors: Sthener R V Campos, Jorge Luis Balino, Ivan Slobodcicov, Durval Florencio FilhoAbstract:Abstract The performance of orifice plates in real-time monitoring of oil, gas and water standard flow rates was investigated. To this end, a multi-rate test was implemented in two production wells routed individually to a test separator in field operational conditions. The well flow rate was varied in steps by changing the choke opening. The ranges of fluid properties and flow conditions achieved during the experiment were: wellhead pressure from 9073 kPa to 13,278 kPa, wellhead temperature from 47.8 °C to 53.5 °C, downstream choke pressure from 6770 kPa to 7913 kPa, downstream choke temperature from 41.6 °C to 49.1 °C, gas–oil-ratio from 1144 Sm 3 / Sm 3 to 2068 Sm 3 / Sm 3 , water-cut from 4.64% to 58.35%, standard oil specific gravity from 0.7988 to 0.8058, standard gas specific gravity from 0.7340 to 0.7550, standard oil flow rate from 46.86 Sm 3 / d to 266.65 Sm 3 / d , standard gas flow rate from 62.68 × 10 3 Sm 3 / d to 296.65 × 10 3 Sm 3 / d , standard water flow rate from 18.06 m 3 / d to 159.33 m 3 / d . The wells tested showed a different dynamic behavior: while well #2 did not vary significantly the stream composition with flow rate, well #1 produced under gas coning, a near well-reservoir phenomenon that governs the contribution of the reservoir gas-cap to the total stream composition. The multi-rate tests generated two data sets with 1424 flow conditions through two flange-tap orifice plates installed upstream (wellhead) and downstream of a cage choke valve. The ranges of orifice variables were: orifice diameter from 0.03479 m to 0.0430 m, beta factor from 0.4946 to 0.6507, differential pressure from 15 kPa to 187 kPa. The virtual metering system presented in Paz et al. (2010) was used to correlate the experimental data. The associated model, suitable for differential pressure measuring devices, includes effects such as flow concentration and slip (through Chisholm’s correlation), generalizing the mass flow rate versus pressure drop relationship for multiphase flow. The total mass flow rate depends on a set of variables evaluated at metering conditions: density and viscosity of the liquid and gas phase, mass quality, pressure drop across the flow meter and geometry (contraction area and beta factor). The determination of the fluid properties at metering conditions was made by using black-oil correlations. These correlations are based on a set of input variables at standard condition that characterizes the stream composition such as gas–oil ratio, water–oil ratio and specific gravities of each phase. A comparison was made between the multiphase flow rates predicted by the model and the ones simultaneously measured at the test separators. The oil, gas and water standard volumetric flow rate deviations (coefficients of variation of the root mean square deviations) were below 3.52 % . It was theoretically demonstrated and experimentally verified that a systematic error exists when the homogeneous model (equal phase velocities) is considered in the formulation, resulting in a flow rate underestimation. When the homogeneous model was used to correlate the data, this effect increased the deviation up to 10.5 % . Flow pattern at the wellhead was characterized as intermittent and annular-mist. Lockhart–Martinelli Parameter varied from 0.362 to 0.836; despite of the experimental data being beyond the wet gas region, the multi-rate tests showed that Chisholm’s over-reading can be successfully extrapolated to these range.
Yuri S. Muzychka - One of the best experts on this subject based on the ideXlab platform.
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A SIMPLE ASYMPTOTIC COMPACT MODEL FOR TWO-PHASE FRICTIONAL PRESSURE GRADIENT IN HORIZONTAL PIPES
2020Co-Authors: M M Awad, Yuri S. MuzychkaAbstract:ABSTRACT A simple semi-theoretical method for calculating two-phase frictional pressure gradient in horizontal pipes using asymptotic analysis is presented. Two-phase frictional pressure gradient is expressed in terms of the asymptotic single-phase frictional pressure gradients for liquid and gas flowing alone. The proposed model uses an asymptotic correlation method to develop a robust compact model. The proposed model can be transformed into either a two-phase frictional multiplier for liquid flowing alone (φ l 2 ) or two-phase frictional multiplier for gas flowing alone (φ g 2 ) as a function of the Lockhart-Martinelli Parameter, X. Single phase friction factors are calculated using the Churchill model which allows for prediction over the full range of laminar-transition-turbulent regions and to allow for pipe roughness effects. The proposed model is compared against published data for a number of pipe diameters. Effect of mass flux on two-phase frictional pressure gradient is also investigated. Comparison with other existing correlations for two-phase frictional pressure gradient such as the Chisholm correlation, the Friedel correlation, and the Müller-Steinhagen and Heck correlation, is also presented Comparison with other existing correlations and experimental data for both φ l and φ g versus X is also presented NOMENCLATURE INTRODUCTION The pressure drop in two-phase gas-liquid flow is an important design Parameter in many engineering applications. Due to its importance, numerous investigations on this topic can be found in the literature. Examples of engineering applications include: chemical industry, nuclear industry, petroleum industry, refrigeration and air-conditioning applications, and space station applications. Total pressure drop for two-phase flow in pipes consists of frictional, acceleration, and gravitational components. It is necessary to know the void fraction (the ratio of gas flow area to total flow area) to compute the acceleration, and gravitational components. To compute the frictional component of pressure drop, either the two-phase friction factor or the twophase frictional multiplier must be known The research on pressure drop in two-phase flow began in the 1940's. Since then, pressure drop and holdup data have been collected for horizontal, vertical, and inclined gas-liquid systems. From the pressure drop and holdup data, many attempts have been made to develop general procedures for predicting these quantities. There are two principal types of frictional pressure drop models in two phase flow: the homogeneous model and the separated model. In the first, both liquid and vapor phases move at the same velocity (slip ratio = 1). Consequently, the homogeneous model has also been called the zero slip model. The homogeneous model considers the two-phase flow as a single-phase flow having average fluid properties depending on mass quality. Thus, the frictional pressure drop is calculated by assuming a constant friction coefficient between the inlet and outlet sections of the pipe. In the second, two-phase flow is considered to be divided into liquid and vapor streams. Hence, the separated model has been referred to as the slip flow model. The separated model was originated from the classical work of Lockhart and Martinelli [2] that was followed by Martinelli and Nelson [3]. The Lockhart-Martinelli method is one of the simplest procedures for calculating two-phase frictional pressure drop and hold up. One of the biggest advantages of the Lockhart-Martinelli method is that it can be used for all flow patterns. However, relatively low accuracy must be accepted for this flexibility. The separated model is popular in the power plant industry. Also, the separated model is relevant for the prediction of pressure drop in heat pump systems and evaporators in refrigeration. The success of the separated model is due to the basic assumptions in the model which are closely met by the flow patterns observed in the major portion of the evaporators
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Bounds on Two-Phase Frictional Pressure Gradient and Void Fraction in Circular Pipes
2014Co-Authors: M M Awad, Yuri S. MuzychkaAbstract:Simple rules are developed for obtaining rational bounds for two-phase frictional pressure gradient and void fraction in circular pipes. The bounds are based on turbulent-turbulent flow assumption. Both the lower and upper bounds for frictional pressure gradient are based on the separate cylinders formulation. For frictional pressure gradient, the lower bound is based on the separate cylinders formulation that uses the Blasius equation to represent the Fanning friction factor while the upper bound is based on the separate cylinders equation that represents well the Lockhart-Martinelli correlation for turbulent-turbulent flow. For void fraction, the lower bound is based on the separate cylinders formulation that uses the Blasius equation to predict the Fanning friction factor while the upper bound is based on the Butterworth relationship that represents well the Lockhart-Martinelli correlation. These two bounds are reversed in the case of liquid fraction (1-α). For frictional pressure gradient, the model is verified using published experimental data of two-phase frictional pressure gradient versus mass flux at constant mass quality. The published data include different working fluids such as R-12, R-22, and Argon at different mass qualities, different pipe diameters, and different saturation temperatures. The bounds models are also presented in a dimensionless form as two-phase frictional multiplier (ϕ l and ϕ g) versus Lockhart-Martinelli Parameter ( X) for different working fluids such as R-12, R-22, and air-water and steam mixtures. For void fraction, the bounds models are verified using published experimental data of void fraction versus mass quality at constant mass flow rate. The published data include different working fluids such as steam, R-12, R-22, and R-410A at different pipe diameters, different pressures, and different mass flow rates. It is shown that the published data can be well bounded for a wide range of mass fluxes, mass qualities, pipe diameters, and saturation temperatures.
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Modeling of Interfacial Component for Two-Phase Frictional Pressure Gradient at Microscales
2014Co-Authors: M M Awad, Yuri S. MuzychkaAbstract:A simple approach for calculating the interfacial component of frictional pressure gradient in two-phase flow at microscales is presented. This approach is developed using superposition of three pressure gradients: single-phase liquid, single-phase gas, and interfacial pressure gradient. The proposed model can be transformed in two different ways: first, two-phase interfacial multiplier for liquid flowing alone (ϕl,i2) as a function of two-phase frictional multiplier for liquid flowing alone (ϕl2) and the Lockhart-Martinelli Parameter, X, and, second, two-phase interfacial multiplier for gas flowing alone (ϕg,i2) as a function of two-phase frictional multiplier for gas flowing alone (ϕg2) and the Lockhart-Martinelli Parameter, X. This proposed model allows for the interfacial pressure gradient to be easily modeled. Comparisons of the proposed model with experimental data for microchannels and minichannels and existing correlations for both ϕl and ϕg versus X are presented.
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A Robust Asymptotically Based Modeling Approach for Two-Phase Flows
2014Co-Authors: M M Awad, Yuri S. MuzychkaAbstract:A simple semitheoretical method for calculating two-phase frictional pressure gradient in horizontal circular pipes using asymptotic analysis to develop a robust compact model is presented. Two-phase frictional pressure gradient is expressed in terms of the asymptotic single-phase frictional pressure gradients for liquid and gas flowing alone. The proposed model can be transformed into either a two-phase frictional multiplier for liquid flowing alone (ϕl2) or two-phase frictional multiplier for gas flowing alone (ϕg2) as a function of the Lockhart-Martinelli Parameter, X. Single-phase friction factors are calculated using the Churchill model which allows for prediction over the full range of laminar-transition-turbulent regions and allows for pipe roughness effects. The proposed model is compared against published data to show the asymptotic behavior. Comparison with other existing correlations for two-phase frictional pressure gradient such as the Chisholm correlation, the Friedel correlation, and the Müller-Steinhagen and Heck correlation, is also presented. Comparison with experimental data for both ϕl and ϕl versus X is also presented. At the end of the paper, the present asymptotic model is also extended to minichannels and microchannels
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Modeling of Interfacial Component for Two-Phase Frictional Pressure Gradient in Microchannels and Minichannels
2011Co-Authors: M M Awad, Yuri S. MuzychkaAbstract:A simple approach for calculating the interfacial component of frictional pressure gradient in two-phase flow in microchannels and minichannels is presented. This approach is developed using superposition of three pressure gradients: single-phase liquid, single-phase gas, and interfacial pressure gradient. The proposed model can be transformed in two different ways. First, two-phase interfacial multiplier for liquid flowing alone (φl,i2) as a function of two-phase frictional multiplier for liquid flowing alone (φl2) and the Lockhart-Martinelli Parameter, X. Second, two-phase interfacial multiplier for gas flowing alone (φg,i2) as a function of two-phase frictional multiplier for gas flowing alone (φg2) and the Lockhart-Martinelli Parameter, X. This proposed model allows for the interfacial pressure gradient to be easily modeled. Comparisons of the proposed model with experimental data for microchannels and minichannels and existing correlations for both φl and φg versus X are presented.Copyright © 2011 by ASME
Yasuyuki Ikegami - One of the best experts on this subject based on the ideXlab platform.
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local boiling heat transfer characteristics of ammonia in a vertical plate evaporator
2010Co-Authors: Hirofumi Arima, A Okamoto, Yasuyuki IkegamiAbstract:Abstract Ocean thermal energy conversion systems are expected to be the next-generation energy production systems. In these systems, a plate heat exchanger is used for improving the power generation efficiency, and ammonia or an ammonia/water mixture is used as a working fluid. In this study, boiling heat transfer coefficients of pure ammonia are measured on a vertical flat PHE (a plate heat exchanger), for elucidating and characterizing the behavior of ammonia on a compact plate evaporator, a type of PHE The measurement results show that local boiling heat transfer coefficients increase with increasing vapor quality. Further, the effects of saturation pressure, mass flow rate, and average heat flux on the boiling heat transfer coefficient are elucidated. An empirical correlation for the local boiling heat transfer coefficient is derived using the Lockhart-Martinelli Parameter. Further, a visualization experiment of boiling phenomena of ammonia is performed to elucidate the relation between boiling behavior and heat transfer.
Bofeng Bai - One of the best experts on this subject based on the ideXlab platform.
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Comparison of throttle devices to measure two-phase flowrates of wet gas with extremely-low liquid loading
2020Co-Authors: Xuebo Zheng, Fan Zhao, Bofeng BaiAbstract:Abstract The online measurement of wet gas with extremely-low liquid loading (Lockhart-Martinelli Parameter lower than 0.02) remains a challenge. In this study, three types of throttle devices, Venturi, orifice plate and cone, are compared experimentally with air-water two-phase flow in a horizontal pipe of inner diameter of 50 mm. High-precision correlations are established to measure the gas and liquid flowrates via a single throttle device. Results show that the two-phase mass flow coefficient (K) of the three throttle devices all increase linearly with the liquid densiometric Froude number and the K correlations are established respectively to correct the gas mass flowrate deviation. The pressure loss ratio (δ) for Venturi is sensitive and monotonous to the liquid loading, which contributes to the high accuracy of liquid flowrate measurement. By incorporating the K correlations, both the gas and liquid mass flowrates can be predicted precisely. The relative error of the gas mass flowrate predicted by the Venturi is within ±2.0% at 95% confidence level, and that of the liquid mass flowrate is within ±15% at 90% confidence level.
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flow patterns and pressure drop of downward two phase flow in a capsule type plate heat exchanger
2019Co-Authors: Chen Jiang, Bofeng BaiAbstract:Abstract Capsule-type plate heat exchanger has wide industrial applications for its low flow resistance and less deposition and fouling. To broaden its application in phase-change heat transfer processes, the flow behaviors including flow patterns and pressure drop were experimentally studied in a vertical downward transparent capsule-type plate channel. Three main flow regimes are identified, which are film flow, plug flow and churn flow. Flow pattern transition criteria for downward two-phase flow in plate channel have been developed. Liquid block forms when the shear stress on the wavy film interface is much larger than the surface tension, which indicates the transition to plug or churn flow from film flow. And plug flow transits to churn flow when the liquid block is over aerated due to the flow turbulence. The transition boundries proposed for capsule-type plate channel show good agreement with the corresponding boundries of chevron-type plate channels. To predict the friction pressure drop, a new correlation containing the mixture Reynolds number is proposed to describe the law between the Lockhart-Martinelli Parameter and liquid two-phase multiplier, which can reflect the effect of mass flux. The comparison of predicted data and experimental results shows good agreement by 82.4% of the data in ±15% error bands.
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A new correlation for wet gas flow rate measurement with Venturi meter based on two-phase mass flow coefficient
2014Co-Authors: Bofeng BaiAbstract:Abstract Much attention has been devoted to the study of the correlation of the wet gas flow rate measurement with a Venturi meter. However, up to now a widely-accepted correlation or model is not available. In this study, a new correlation for wet gas flow rate measurement with Venturi meter based on a two-phase mass flow coefficient was proposed. The two-phase mass flow coefficient was found to linearly increase with the Lockhart–Martinelli Parameter and decrease with the increase of the gas-to-liquid density ratio. It also decreased with the gas densiometric Froude number increasing. The relationships of the two-phase mass flow coefficient with the Lockhart–Martinelli Parameter, the gas densiometric Froude number and the ratio of gas to liquid density were concluded. Comparisons with the existing correlations showed that the new correlation predicted the wet gas flow rate more accurately than other correlations under the following conditions: the Lockhart–Martinelli Parameter ranging from 0 to 0.3, the gas densiometric Froude number from 0.6 to 4.7, the ratio of gas to liquid density from 0.01 to 0.081 and the inlet diameter of the Venturi meter from 50 to 200 mm. The present work provided an alternative approach to the study on the wet gas flow rate measurement with the Venturi meter.