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چكيده انگليسي :

Investigation on the Behavior of Flow in a Finger Type Slug Catcher BabakSoltaniDehnavi atabakan1@gmail com 14 April 2012 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiA Alemrajabi rajabi@cc iut ac irA Sabounchi ahmadsab@cc iut ac irAbstract Nowadays there are multiphase flows in different industries and it is important to investigate these flows Sofar many people have researched on these flows and investigated from different aspects The most importantchallenge for investigation of these flows is presentation of a suitable model for them The multiphase flowinside the pipelines has different forms that are called flow regimes In fact flow regimes are different statesof flow that different phases in a multiphase flow have relative to each other Since the flow regimes areeffective in pipeline design a lot of researches have been done for flow regimes prediction Stratified andSlug flows are samples of flow regimes The slug flow exerts additional stresses on pipelines It is desirableto prevent this regime in the pipelines One of the equipments that is used for this application is slug catcher The slug catchers have various types Finger type slug catchers are usually used in downstream of pipeline orentrance of gas refineries The flow regime in slug catcher is stratified to prevent slugs flows enter refinery In slug catchers flow is splited into different phases to improve performance of downstream equipments In this thesis different types of flow regimes are investigated and map of flow regimes are shown Alsodifferent types of slug catchers and splitting mechanisms in them are discussed Thereafter equations forstratified and slug regimes are given Types of stratified regimes with flat curved and wavy interfaces andtheir equations are investigated Thereafter different kinds of turbulence models are used At the end flow ina slug catcher is simulated with ANSYS CFX and influence of fingers slope flow rate and adding reducers atentrance of fingers on flow in slug catcher are investigated The results indicated that increasing the pressureat a given flow rate leads to decreasing the flow level in slug catcher fingers Diagram of inlet volume flowrate related to different finger slopes are drawn and compared with same diagram for St Fergus and DenHelder slug catchers According to this diagram optimum slope for South Pars slug catchers is about 1 5 Inthis thesis also effect of inlet gas and liquid superficial velocity on flow distribution in fingers and inletvolume of liquids into the gas risers investigated The results showed that in general increasing the amount ofliquid superficial velocity at a fixed gas superficial velocity decreases gas inlet to the risers and increasing thegas superficial velocity at a fixed liquid superficial velocity will increase inlet of liquid to gas risers Theresults showed that if the expander inserted instead of equal size pipe distribution of mass flow in the fingerswill be improved In this case mass flow distribution in fingers with 44 48 expander is better than 42 48 and 40 48 expanders The results showed that with increasing the size of expanders from 40 48 to44 48 inlet momentum of liquid and gas and volume of liquids in fingers will be decreased Also in thisthesis showed that best turbulence model to simulate the flow in slug catcher is SST Keywords Multiphase flow Stratified flow Slug flow Turbulence Models Finger Type Slug Catcher

سلطاني دهنوي، بابك

بربسي عددي رفتار جريان در يك لخته گيرانگشتي

جريان چند فازي , رژيم لايه اي , رژيم اسلاگ , مدلهاي توربولاتسي