Browsing by Author "Al-Lababidi, Salem"
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Item Open Access Multiphase flow measurement in the slug regime using ultrasonic measurement techniques and slug closure model(Cranfield University, 2006-06) Al-Lababidi, Salem; Sanderson, M. L.Multiphase flow in the oil and gas industry covers a wide range of flows. Thus, over the last decade, the investigation, development and use of multiphase flow metering system have been a major focus for the industry worldwide. However, these meters do not perform well in slug flow conditions. The present work involves experimental investigations of multiphase flow measurement under slug flow conditions. A two-phase gas/liquid facility was designed and constructed at Cranfield University. It consisted of a 0.05 m diameter 25 m long horizontal pipeline with the necessary instrumentation. An ultrasonic multiphase metering concept has been proposed and investigated. The concept was based on the combination of non-invasive and non-intrusive ultrasonic sensors and a slug closure model. The slug closure model was based on the "slug unit" model to infer the gas and liquid phase volumetric flowrates. The slug characteristics obtained by non-invasive and non-intrusive ultrasonic techniques were inputs to slug closure model which calculates the factors KI (Liquid), K2 (Liquid), K3 (Gas) and K4 (Gas). These factors are function of the slip ratio in the slug body, flow profile (CO), drift velocity (Vd), liquid holdup and gas void fraction in slug body, slug length, film length, and the total length of the slug unit. Based on ultrasonic sensor measurements, the slug translational velocity was estimated and the slug closure model then calculates the gas and liquid phase volumetric flowrates. Air water slug flow data were gathered and processed for a range of superficial velocities VSL=0.3 to 1.03 ms'1 and VsG=0.6 to 3.01 ms'1. The overall goal of a 5% relative error metering for both phases was not achieved for the conditions tested. The liquid phase percentage errors were from -63.6% to 45.4% while the gas phase percentage errors were from 42% to -14.6%. Key words: slug flow, slug characteristics, slug closure model, non-invasive ultrasonic, non-intrusive ultrasonic, clamp-on transit time ultrasonic flowmeter.Item Open Access Viscosity effects on sand flow regimes and transport velocity in horizontal pipelines(Elsevier, 2017-08-26) Yeung, Hoi; Yan, Wei; Al-Lababidi, Salem; Zorgani, E.; Fairhurst, C. P.; Al-Awadi, H.Solids transport in multiphase systems is one of the issues under the umbrella of ‘‘flow assurance.’ But unlike issues such as waxes and hydrates, solids transport has received relatively little interest to date. The overall aim of this research was to investigate the fluid viscosity effects on sand particle transport characteristics in pipelines. Investigations were conducted using a 3-inch test facility for oil and a 4- inch flow loop for water and CMC experiments. Three oil viscosities were used including 105 cP, 200 cP and 340 cP. The sand used had a density of 2650 kg/m3 and a median diameter of 0.2 mm. The sand loadings were 50 lb/1000 bbl and 200lb/1000bbl. Based on the King et al (2000) sand minimum transport condition definition, the sand transport velocity for water, CMC solutions and oil (105 cP, 200 cP and 340 cP) were determined by visual observation and camera. The observed sand/oil flow regimes were compared. For oil/sand tests, it was observed that the dominant regime when approaching the critical sand transport velocity was the sliding sand bed, sand dunes were notably absent. However, for water and 7 cP CMC solution, sand dunes and sliding sand bed regimes were observed when approaching the sand transport velocity. For 20cP CMC solution, it was observed that the sand particles in the region between the main dunes were very active compared to those within the dunes.