118 research outputs found

    Two-phase flow meter for determining water and solids volumetric flow rate in vertical and inclined solids-in-water flows

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    Multiphase flow can be defined as the simultaneous flow of a stream of two or more phases. Solids-in-water flow is a multiphase flows where solids and liquid are both present. Due to the density differences of the two phases, the results for such flow is often to have non-uniform profiles of the local volume fraction and local axial velocity for both phases in the flow cross-section. These non-uniform profiles are clearly noticeable in solids-in-water stratified flow with moving bed for inclined and horizontal pipelines. However in many industrial applications, such as oil and gas industry, food industry and mining industry, multiphase flows also exist and it is essentially important to determine the phase concentration and velocity distributions in through the pipe cross-section in order to be able to estimate the accurately the volumetric flow rate for each phase. This thesis describe the development of a novel non-intrusive flow meter that can be used for measuring the local volume fraction distribution and local axial velocity distributions of the continuous and discontinuous phases in highly non-uniform multiphase flows for which the continuous phase is electrically conducting and the discontinuous phase is an insulator. The developed flow meter is based on combining two measurement techniques: the Impedance cross correlation ICC technique and the electromagnetic velocity profiler EVP technique. Impedance cross correlation ICC is a non-invasive technique used to measure the local volume fraction distributions for both phases and the local velocity distribution for the dispersed phase over the pipe cross-section, whilst the electromagnetic velocity profiler EVP technique is used to v measure the local axial velocity profile of the continuous phase through the pipe cross-section. By using these profiles the volumetric flow rates of both phases can be calculated. A number of experiments were carried out in solid-in-water flow in the University of Huddersfield solids-in-water flow loop which has an 80 mm ID and an approximately 3m long working section. ICC and EVP systems were mounted at 1.6 m from the working section inlet which was inclined at 0 and 30 degree to the vertical. The obtained result for the flow parameters including phase volume fraction and velocity profiles and volumetric flow rates, have been compared with reference measurements and error sources of difference with their reference measurements have been identified and investigated

    Metering of two-phase slug flow

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    This thesis describes the development of a novel system, for metering of two-phase (gaswater) slug flows. The approach combines a model for stable slug flow, a non-intrusive set of conductance sensors, and appropriate closure relationships. This system allows each of the parameters in the model to be determined. The slug flow model is analysed, to determine the sensitivity of the phase flowrates to each measurement parameter. A metering system is then proposed which combines ring-shaped electrodes, electronic instrumentation, and processing software. The ring electrodes are optimised, for the measurement of the phase fraction and the translation velocity. New instrumentation is developed to activate the electrodes, with high measurement accuracy and a wide bandwidth. Analysis software is developed, to process the sensor data, provide suitable closure relations, and deliver the flowrates. A unique feature of this software is its ability to calculate uncertainty margins in the predicted flowrates. The NEL multiphase facility is used, to obtain data for developed, horizontal, gas-water slug flow in a 4-inch pipe. The data span the range of liquid phase superficial velocities 0.1 m s⁻Âč to 1.0 m s⁻Âč , and gas phase superficial velocities 0.6 m s⁻Âč to 6.0 m s⁻Âč. The analysis software is used to obtain the flowrate predictions and estimates for the uncertainty margins. The stable slug flow model does not give good results. The relative error in the gas phase prediction is between 10% and 100%, and for the liquid phase prediction, between 50% and 500%. The uncertainty margins are also of comparable magnitude. Proposals for improving the accuracy of the translation velocity measurement, and for directly measuring the local velocities in the slug body (using a pressure transducer) are presented. These proposals aim to reduce the uncertainty that is caused by the use of the empirical closure relationships in the model.This thesis describes the development of a novel system, for metering of two-phase (gaswater) slug flows. The approach combines a model for stable slug flow, a non-intrusive set of conductance sensors, and appropriate closure relationships. This system allows each of the parameters in the model to be determined. The slug flow model is analysed, to determine the sensitivity of the phase flowrates to each measurement parameter. A metering system is then proposed which combines ring-shaped electrodes, electronic instrumentation, and processing software. The ring electrodes are optimised, for the measurement of the phase fraction and the translation velocity. New instrumentation is developed to activate the electrodes, with high measurement accuracy and a wide bandwidth. Analysis software is developed, to process the sensor data, provide suitable closure relations, and deliver the flowrates. A unique feature of this software is its ability to calculate uncertainty margins in the predicted flowrates. The NEL multiphase facility is used, to obtain data for developed, horizontal, gas-water slug flow in a 4-inch pipe. The data span the range of liquid phase superficial velocities 0.1 m s⁻Âč to 1.0 m s⁻Âč , and gas phase superficial velocities 0.6 m s⁻Âč to 6.0 m s⁻Âč. The analysis software is used to obtain the flowrate predictions and estimates for the uncertainty margins. The stable slug flow model does not give good results. The relative error in the gas phase prediction is between 10% and 100%, and for the liquid phase prediction, between 50% and 500%. The uncertainty margins are also of comparable magnitude. Proposals for improving the accuracy of the translation velocity measurement, and for directly measuring the local velocities in the slug body (using a pressure transducer) are presented. These proposals aim to reduce the uncertainty that is caused by the use of the empirical closure relationships in the model

    Cumulative index to NASA Tech Briefs, 1970-1975

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    Tech briefs of technology derived from the research and development activities of the National Aeronautics and Space Administration are presented. Abstracts and indexes of subject, personal author, originating center, and tech brief number for the 1970-1975 tech briefs are presented

    Multiphase flow measurement using gamma-based techniques

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    The oil and gas industry need for high performing and low cost multiphase meters is ever more justified given the rapid depletion of conventional oil reserves. This has led oil companies to develop smaller/marginal fields and reservoirs in remote locations and deep offshore, thereby placing great demands for compact and more cost effective soluti8ons of on-line continuous multiphase flow measurement. The pattern recognition approach for clamp-on multiphase measurement employed in this research study provides one means for meeting this need. Cont/d

    Innovation: Key to the future

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    The NASA Marshall Space Flight Center Annual Report is presented. A description of research and development projects is included. Topics covered include: space science; space systems; transportation systems; astronomy and astrophysics; earth sciences; solar terrestrial physics; microgravity science; diagnostic and inspection system; information, electronic, and optical systems; materials and manufacturing; propulsion; and structures and dynamics

    Small business innovation research. Abstracts of 1988 phase 1 awards

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    Non-proprietary proposal abstracts of Phase 1 Small Business Innovation Research (SBIR) projects supported by NASA are presented. Projects in the fields of aeronautical propulsion, aerodynamics, acoustics, aircraft systems, materials and structures, teleoperators and robots, computer sciences, information systems, data processing, spacecraft propulsion, bioastronautics, satellite communication, and space processing are covered

    Ancient and historical systems

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    NASA Tech Briefs, December 1990

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    Topics: New Product Ideas; NASA TU Services; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences

    Cumulative index to NASA Tech Briefs, 1986-1990, volumes 10-14

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    Tech Briefs are short announcements of new technology derived from the R&D activities of the National Aeronautics and Space Administration. These briefs emphasize information considered likely to be transferrable across industrial, regional, or disciplinary lines and are issued to encourage commercial application. This cumulative index of Tech Briefs contains abstracts and four indexes (subject, personal author, originating center, and Tech Brief number) and covers the period 1986 to 1990. The abstract section is organized by the following subject categories: electronic components and circuits, electronic systems, physical sciences, materials, computer programs, life sciences, mechanics, machinery, fabrication technology, and mathematics and information sciences
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