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Experimental Investigation of Two-Phase (Gas/Liquid) Flow in Intermediate Sized, Horizontal and Inclined Pipes

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Experimental Investigation of Two-Phase (Gas/Liquid) Flow in Intermediate Sized, Horizontal and Inclined Pipes University of South Carolina Scholar Commons Theses and Dissertations Fall 2018 Experimental Investigation of Two-Phase (Gas/ Liquid) Flow in Intermediate Sized, Horizontal and Inclined Pipes Noble C. Anumbe Follow this and additional works at: https://scholarcommons.sc.edu/etd Part of the Mechanical Engineering Commons Recommended Citation Anumbe, N. C.(2018). Experimental Investigation of Two-Phase (Gas/Liquid) Flow in Intermediate Sized, Horizontal and Inclined Pipes. (Doctoral dissertation). Retrieved from https://scholarcommons.sc.edu/etd/5052 This Open Access Dissertation is brought to you by Scholar Commons. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Experimental investigation of two-phase (gas/liquid) flow in intermediate sized, horizontal and inclined pipes by Noble C. Anumbe Bachelor of Engineering Nnamdi Azikiwe University, 2001 Master of Science The Robert Gordon University, 2007 Submitted in Partial Fulfillment of the requirements For the Degree of Doctor of Philosophy in Mechanical Engineering College of Engineering and Computing University of South Carolina 2018 Accepted by: Jamil Khan, Major Professor Chen Li, Committee Member Jasim Imran, Committee Member Tanvir Farouk, Committee Member Cheryl L. Addy, Vice Provost and Dean of the Graduate School Copyright © 2018 by Noble C. Anumbe All rights reserved ii Dedication To my late dad (Mr. Samuel Chukwuemeka Anumbe) who was my model and a great inspiration. Thank you for laying this foundation right! To my mum (Mrs Abigail Nwure Chukwuemeka)...who remains my rock and support. For your wise counsel, sympathetic ear and indeed, all the sacrifices you made to get me to this point To my siblings...Kinglsey (Chinedu), Queen (Enyinne), Sharon (Nnenna) and Prince (Chinemerem)...for your enduring love, patience, fraternal friendship and unending camaraderie. And finally...to the only wise GOD and creator of the heavens and the earth, before whom all men of courage, knowledge and wisdom, shall yet bow. Thank YOU! Words cannot express how much I appreciate and love you all. iii Acknowledgments First, I would like to thank the Mechanical Engineering Department at the University of South Carolina for the provision of the space and support to work through this program. I am extremely grateful and would like to express my deepest appreciation to my adviser and committee chair Professor Jamil Khan, whose support and faith were unflinching. His patience, "fatherly" guidance and intense support can best be described as immeasurable. I know for a certainty that without his guidance and persistent help, this dissertation and my overall journey at the University of South Carolina would have played out rather differently. I also wish to thank members of my dissertation committee (Dr. Tanvir I. Farouk, Dr. Chen LI, and Dr. Jasim Imran) their support as my research interests morphed from ideas to a completed study. I appreciate the many hours of direct counsel, listening to presentations, reviewing my findings and asking tough questions. Similar, gratitude goes to the Mechanical Lab Manager: Bill Bradley, who spent countless hours listening to my design ideas, contributing his "two cents", and patiently working through many iterations to arrive at that "near perfect" test facility. I still have fond memories of my time in the workshop, particularly of the recollections of students asking if I was a technical staff at the workshop because of my long and constant presence in the machine shop. You also have Nabeel M. Abdulrazzaq, Azzam S. Salman, Ahmed Musfi Abir, Amitav Tikadar and Saad K. Oudah; members of my research group. During the experimental campaign, this team spent countless hours deliberating over and resolving "pop-up" experimental problems and discussing findings, not to mention constantly listening to me talk and sometimes just ramble about my research. iv I am also hugely appreciative of the help of the administrative staff at the de- partment (Renee Jenkins, Misty O'Donnell & Lalitha Ravi). Special mention goes to Lalitha Ravi who supported me greatly and was always willing to help me even beyond the call of duty. I appreciate the office of the Vice President for Research at the University of South Carolina for co-funding this work through the SPARC Graduate Research Grant. I am indepted to the Institute of Fluid Dynamics, Helmholtz-Zentrum Dresden- Rossendorf (HZDR), Germany for their technical partnership.They graciously supplied the Wire-mesh sensor (WMS) and the on-going technical for this project. I feel extremely privileged to have had the opportunity to partner with this world renown research Institute. I would like to specifically thank Prof. Dr.-Ing. habil. Uwe Hampel, for the project support. Special mention to Eckhard Schleicher and Christoph Schunk who were my direct contacts. Their availability and technical support were both unbelievably timely, prompt and invaluable. Finally, I use this opportunity to express my gratitude to my family for their undying love, unfailing commitment and unconditional support. Special mention to my Uncle, Ikechi Ubani who was always there in the course of the journey especially when it mattered most. v Abstract Multiphase flow models and correlations are indispensable tools for the design and operation of vital flow systems that power various industries. The development, validation and tuning of these flow models & correlations depend on the availability of reliable and accurate data. This dissertation reports on an experimental campaign that not only generated crucial two-phase flow data but also evaluated the effect of inclination angle on several flow parameters of interest. The report details the experimental investigation of upward, adiabatic, co-current two-phase (gas/liquid) flow through a 101.6 mm inner diameter (ID) pipe. Experimental data for the investigation were acquired using an industrial scale, inclinable test rig designed and commissioned at the University of South Carolina. The fully instrumented test rig was equipped with a 7.3 m long, 101.6 mm inner diameter (ID) pipe and outfitted with a range of flow control devices, measurement instrumentation, flow condition monitoring sensors and a robust flow supply, transmission and storage system. The test fluids employed were air (1.2 kg/m3, 2.0 × 104Pa·s ) and water (998 kg/m3, 0.001 Pa·s, 0.072 N/m). All tests were operated at ambient temperature and pressure, approximately. The superficial gas and liquid velocities (JL &JG) ranged between (0.311-2.489 m/s) and (0.622-2.801 m/s), respectively. Two-phase flow regime, void fraction and pressure drop data were acquired using a high-speed camera, a dual Wire mesh sensor (WMS) and a differential pressure (DP) gauge, respectively. All data were collected at six (6) different orientation angles between 0° and 75° (from horizontal). The effect of the variation of inclination angles on different flow parameters including flow regime, void fraction and pressure drop were investigated and reported. It was determined that inclination angle has significant effect on all flow parameters. vi The observed variations were found to have been dictated by specific flow conditions and the effect of several forces including buoyancy, gravity, surface tension, inertia etc. Flow regime maps were also developed for all orientations investigated, and local processes within the regime transition zones analyzed. The data acquired provided insight into the hydrodynamic behavior of two-phase (gas/liquid) flow in relatively large diameter pipes at various inclinations, extending beyond the near-horizontal and near-vertical range that are commonplace in literature. The data would also be a valuable contribution to the two-phase (gas/liquid) database and provide potential future value for flow model and correlation development/improvement. vii Preface This dissertation is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the University of South Carolina. The bulk of the research conducted for this dissertation is the subject of an international collaboration between the University of South Carolina, Columbia SC (hereafter referred to as Univ. of SC and Helmholtz-Zentrum Dresden-Rossendorf (hereafter referred to as HZDR), Germany. While HZDR provided the Wire-mesh sensor, sensor electronics & software, alongside with all necessary technical support, I served as the lead investigator on the Univ. of SC side and performed all experimental work and subsequent data analysis. Prof. Jamil Khan served as the Principal Investigator (PI) and lead sponsor on the Univ. of SC side while Prof. Dr.-Ing. Habil. Uwe Hampel and Eckhard Schleicher led the HZDR representation. All the experimental work was conducted at the Univ. of SC, Columbia, SC. The test facility referred to in Chapter (4) was primarily designed by the author, with the assistance of Professor Jamil Khan, and inputs from Dr. Dale McCants and Bill Bradley (Univ. of SC Mechanical Workshop Manager). The dissertation introduction in Chapter (1), subject matter technical overviews in Chapter (2) & (3), data analysis in chapter (6)(7) & (8) and discussions/concluding remarks in (9) are all my original work except where acknowledgments and references are made to previous work. Some portions of the work have been presented at the 2018 annual American Society of Thermal and Fluids Engineers (ASTFE) conference and published in the ASTFE Conference Proceedings. The publication is entitled, The effect of inclination on pressure drop in a two-phase (gas-liquid) pipe system and is available in in the ASTFE Digital Library. viii The ASTFE Digital Library was developed by and is maintained by Begell House Publishers, Inc. Several other publications from this work are either under review or in consideration. ix Table of Contents Dedication . iii Acknowledgments . iv Abstract . vi Preface . viii List of Figures . xiv List of Tables . xvii Chapter 1: Introduction . 1 1.1 Background . 1 1.2 Motivation and Background to the research . 3 1.3 Problem Statement . 4 1.4 The objective of the study: .
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