Liquid holdup in two phase flow pdf

Gasliquid two phase flow occurs extensively in petroleum industry. Summary liquid holdup behavior in twophase inclined flow was studied in an inclined pipeflow simulator. Due to gravitational differentiation, oilwater twophase flow pattern, the local velocity and local phase holdup along the radial direction of pipe in near horizontal wells. In order to extend the applicable range of existing liquid holdup prediction models and improve its prediction accuracy, a of gasliquid twophase flow experiment was carried out using a pipe of inner diameter 60mm and length of 11. Although such analyses attempt to give some physical insight into the flow mechanism, they inevitably entail gross simplifications and empiricism.

Two sets of empirical equations, one each for uphill and downhill flow, are presented. Void fraction measurement of gasliquid twophase flow. Measured liquid holdup at various gas and liquid flow rates in. The holdup of a particular fluid is not the same as the proportion of the total flow rate due to that fluid, also known as its cut.

Experimental study of the interfacial waves in horizontal. The liquid slugs and gas pockets propagate alternatively in the pipe. Hydrodynamics of gasliquid flow in micropacked beds. The gas and liquid phases are separated by an interface that can be smooth or wavy. When the flow rate is increased, the liquid holdup in the line decreases. A decrease, not far from linear, in the liquid holdup was observed as the gas flow increases. Liquid holdup correlations for inclined twophase flow. Holdup for twophase flow of gasnonnewtonian liquid mixtures in horizontal and vertical pipes. The subscripts g and f indicate the vapor and liquid phase at saturation, respectively. Here, we only consider the qualitative features of gasliquid flow in a horizontal pipe to give you an appreciation of the complexity of twophase flow when compared with the flow of a single fluid phase. A new model for predicting liquid holdup in twophase flow. Spe 10923 liquid holdup correlations for inclined two. The predictions of flow pattern, liquid holdup and pressure losses.

Flow regimes in horizontal twophase flow typical velocities ms regime 1. The twouid model was developed by establishing and solving a momentum equation for. Such annular flow is frequently appeared in many types of. Calculation of the twophase density requires knowledge of the liquid holdup. Pdf estimating slug liquid holdup in high viscosity oil. Liquid hold up occurs in 2phase gas and liquid flow through pipelines where the gas superficial velocity is higher than the liquid and some degree of liquid inventory is held up in the pipeline. The engineers developed the terminology rather than the chemists.

Slug flow of gasliquid twophase is invariably encountered in inclined wells and horizontal wells of a producing environment. Experimental study of pressure gradients occurring during. This change in holdup can either exit the line as a steady flow with increased liquid production, or it can come out in the form of a slug, depending on the flow rate change. In order to correct the measuring equipment, not only is the liquid holdup needed, but also the flow pattern of the twophase flow 3. Gasliquid two phase flow through a vertical 90 degrees. There are several flow patterns of twophase flow in a horizontal pipe, and one of them is stratified twophase flow pattern 7. Multiphase flow correlations are used to predict the liquid holdup and frictional pressure gradient. Liquid holdup in horizontal twophase gasliquid flow. In multiphase flow, each fluid moves at a different speed due to different gravitational forces and other factors, with the heavier phase moving slower, or being more held up, than the lighter phase.

For higher liquid rates, the flow pattern was always pseudoslug flow. Liquid holdup in horizontal twophase gasliquid flow sciencedirect. In twophase gasliquid flow, the slug flow always happens due to an increasing gas superficial velocity. Pdf a new model for prediction of liquid holdup in twophase. In the packed column with a novel internal, which is made of several structured porous passages, gas is divided into two branches which meet liquid in countercurrent and crosscurrent, respectively, so the excessive pressure drop and flooding of conventional gas. Liquid holdup and dispersion in packed columns pdf free. The liquid volume fraction in the slug body of gasliquid twophase flow is recognized as the slug liquid holdup. Flow regimes in vertical upward two phase flow according to hewitt 2012 8 fig. A condition in twophase flow through a vertical pipe. Analysis of low liquid loading twophase flow using cfd. For downhill stratified flow, a third equation is presen.

They are therefore more correctly termed twophase flow correlations. Martinelli type of correlation for horizontal flow. Analysis of gas and liquid twophase slug flow production. Pdf liquid holdup in horizontal twophase gasliquid flow. The correlation is based on 112 pressure profiles consisting of 960 field measured pressure losses 340 tests for horizontal, 500 for vertical and 120 for inclined flow cover very wide range of all flow parameters. A model for predicting dynamic liquid holdup is presented. Neither liquid holdup nor flow pattern was measured during the hagedorn and brown study, although a correlation for the calculated liquid holdup is presented. Schematic flow diagram of the apparatus used by the author. Then the liquid holdup can be calculated as water cut is defined as the ratio of the water volumetric flowrate to. Pressure drop, holdup and flow pattern data were successfully obtained simultaneously in the three vertical tubes, each 17. Lecture 14 multiphase flows applied computational fluid. Hughmark 1962 slip correlation either horizontal or vertical flow. Effects of surface tension on the liquid holdup and wave. Relief valves for twophase gas liquid flow, chemical engineering, 109, no.

When gas and liquid flow concurrently in a pipe, the gas normally travels faster than the liquid, causing a slippage between the phases. The sketches on the following pages depict various regimes of cocurrent twophase flow. Liquid holdup equations are functions of dimensionless liquid and gas velocity numbers in addition to liquid viscosity number and angle of inclination. Keywords twophase flow, annular flow, surface tension, interfacial friction 1. Notes on twophase flow, boiling heat transfer, and. Liquid holdup in horizontal twophase gasliquid flow article pdf available in journal of petroleum science and engineering 1524.

Abstract twophase flow in pipes occurs frequently in refineries, oil and gas production facilities and petrochemical. Some researchers used the twouid model to calculate liquid holdup of strati ed and annular ow regimes 2224. Materials with different chemical properties but in the same state or phase i. This paper presents a new correlation for estimating liquid holdup in horizontal, vertical and inclined upward twophase flow. Effects of surface tension on liquid film behavior and. Introduction gasliquid annular twophase flow is the flow which is composed of annular liquid film on the tube wall and a continuous gas core with or without liquid entrainments. Ratio of the velocity of the gas phase to the velocity of the liquid phase. Pdf liquid holdup correlation for horizontal, vertical. Calculated liquid depth against specific energy for the free surface channel flow in a downward inclined circular conduit 4. Liquid holdup article about liquid holdup by the free. The prediction of liquid holdup in horizontal pipe with bp. A new model for predicting liquid holdup in twophase ow. The development of shale gas reservoir is mainly based on horizontal well production.

All of this makes the modelling and analysis of low liquid loading, or wet gas, flow very important for the industry. Estimation of pressure drop, liquid holdup and flow. Argonwater is an instance of twophase twocomponent flow. Airwater is an example of twophase multi component flow. Pdf a new model for prediction of liquid holdup in two. The wave characteristics of horizontal annular twophase flow in 16 mm diameter pipe were experimentally investigated using flushmounted constant electric current method cecm sensors and visual observations. Due to gravitational differentiation, oilwater twophase flow pattern, the local velocity and local phase holdup along the radial direction of pipe in near horizontal wells will perform complicatedly. Liquid holdup behavior in twophase inclined flow was studied in an inclined pipeflow simulator.

The superficial gas and liquid velocity ranges were. In homogeneous gas and liquid two phase flow, there is not slippage between gas and liquid, and the slip velocity equals zero. Holdup in twophase, gasliquid flowitheoretical aspects. Experimental study of pressure gradients occurring during continuous twophase flow in smalldiameter vertical conduits abstract alton r. A new model for prediction of liquid holdup in two phase flow under higher gas and liquid velocities article pdf available october 2018 with 214 reads how we measure reads. Liquid holdup correlations for inclined twophase flow onepetro. Experimental investigations have been carried out to evaluate the twophase pressure drop and the holdup for flow through helical coils. Some researchers used the two uid model to calculate liquid holdup of strati ed and annular ow regimes 2224. Identification of the range of small diameter conduits regarding twophase flow patterns transitions.

It is recognized by the liquid phase flows along the bottom of the pipe whereas the gas phase flows cocurrently above it. The coils were made of thick wall transparent pvc tube of diameter 0. The correlation was developed by assuming that the twophase friction factor would be obtained from the moody diagram, based on two phase reynolds number. Actually, the terms twocomponent flow and twophase flow are often used rather loosely in the literature to mean liquidgas flow and liquidvapor flow respectively. The wavystratified flow pattern was observed for the liquid rates of 610. The two uid model was developed by establishing and solving a momentum equation for. For twophase flow, it is necessary to supplement mass, momentum and energy balance relations by empirical correlations for 1 friction factor, and 2 liquid holdup. It is the difference between the velocity of gas and liquid. Based on the measured data, it was found that taiteldukler model tends to overestimate liquid holdup for stratified wavy, slug and annular flow. To extend the applicable range of existing liquid holdup prediction models and improve their prediction accuracy, a gasliquid twophase flow.

In this study, set of explicit equations to predict the liquid holdup in inclined stratified, twophase, gasliquid flow has been developed. The fluid flow in a geothermal well is not amenable to strict analytical treatment. Holdup in two phase flow 331, a i s e i,j stratified fw o 6. Estimating slug liquid holdup in high viscosity oilgas two phase flow article pdf available in flow measurement and instrumentation 65 october 2018 with 221 reads how we measure reads. Pdf holdup in twophase, gasliquid flowitheoretical. The value of liquid holdup varies from zero for singlephase gas flow to one for single phase liquid. Liquid holdup correlation for horizontal, vertical and. Experimental study of gasliquid twophase flow for high. Schematic diagram of the two phase pressure loss in a horizontal. The liquid hold up is dependant of the gas velocity relative to the liquid velocity as well as fluid properties density and viscosity, interfacial. In the homogeneous model, the two phases are assumed to be travelling at the same velocity in the channel and the flow is treated as being analogous to a single phase flow see article on multiphase flow separated flow models. A twophase flow model to predict liquid holdup and pressure. Tell a friend about us, add a link to this page, or. Spe 10923 liquid holdup correlations for inclined twophase flow.

Liquid holdup for twophase countercurrent flow in the. Liquid holdup in concurrent gas liquid upflow through. I am still of opinion that controlling twophase flow is impossible in real systems, simply because of high influence of hydraulics liquid holdup, flow regime on control valve performance and actual flow and that was the original question estimating phase flows through a valve with known cv of both liquid and vaporgas phases through the. Liquid holdup correlation for inclined twophase stratified flow in pipes ahmed saib naji abstract. A wide range of models have been developed for twophase flow systems. Experimental study of liquid holdup of liquidgas two. The pressure drop, residence time distribution, and liquid holdup are measured with gas and liquid flow rates varying from 4. Slug flowa description bubbles of gas dispersed throughout the liquid plugs of gas in liquid phase layer of liquid with a.

Variation of total liquid holdup with gas f low rate as a function of liquid flow rate for airwater sys tem fig. This study is similar to abdul majeeds study for predict the liquid holdup in horizontal pipes. Flow pattern transitions in two phase liquidliquid horizontal tubes international journal of multiphase flow 18. A statistical correlation for holdup was developed to include fluid physical properties, total mass. Correlations in common use consider liquidgas interactions the oil and water are lumped together as one equivalent fluid. Three equations for twophase density are used by various investigators in twophase flow. Existing liquid holdup models are generally based on low gas and liquid velocities. Moody diagram, as the use of the smoothpipe equation results in. To examine the effect of surface tension on the wave velocity and frequency, air and three kinds of liquids with different surface tension were used, i.

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