FLOW MEASUREMENT Edited by Gustavo Urquiza Beltrán and Laura L. Castro Gómez           Flow Measurement Edited by Gustavo Urquiza Beltrán and Laura L. Castro Gómez Published by InTech Janeza Trdine 9, 51000 Rijeka, Croatia Copyright © 2012 InTech All chapters are Open Access distributed under the Creative Commons Attribution 3.0 license, which allows users to download, copy and build upon published articles even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. After this work has been published by InTech, authors have the right to republish it, in whole or part, in any publication of which they are the author, and to make other personal use of the work. Any republication, referencing or personal use of the work must explicitly identify the original source. As for readers, this license allows users to download, copy and build upon published chapters even for commercial purposes, as long as the author and publisher are properly credited, which ensures maximum dissemination and a wider impact of our publications. Notice Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published chapters. The publisher assumes no responsibility for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained in the book. Publishing Process Manager Vana Persen Technical Editor Teodora Smiljanic Cover Designer InTech Design Team First published March, 2012 Printed in Croatia A free online edition of this book is available at www.intechopen.com Additional hard copies can be obtained from orders@intechopen.com Flow Measurement, Edited by Gustavo Urquiza Beltrán and Laura L. Castro Gómez p. cm. ISBN 978-953-51-0390-5    Contents  Preface IX Part 1 Microflows Measurement 1 Chapter 1 Challenges in Microflow Measurements 3 Boguslaw Kruczek and Siamak Lashkari Part 2 Biphasic Flow Measurement 37 Chapter 2 Gas-Liquid Two-Phase Flow Rate Measurements by Flow Division and Separation Method 39 Dong Wang Chapter 3 Measurement of Two-Phase Flow Structure in a Narrow Rectangular Channel 73 Daisuke Ito and Horst-Michael Prasser Chapter 4 Development of Capacitance Void Fraction Measurement Method for BWR Test 95 Hironori Watanabe, Hidesada Tamai, Takashi Satoh, Mitsuhiko Shibata and Toru Mitsutake Part 3 Gas Flow Measurement 107 Chapter 5 Experimental Procedure for Rotating Ventilated Disk 109 Kannan M. Munisamy Chapter 6 The LDV and PIV Study of Co-Rotating Disks Flow with Closed Shroud 127 Shen-Chun Wu Part 4 Indirect Flow Measurement 149 Chapter 7 Flow Measurement Methods Applied to Hydro Power Plants 151 Gustavo Urquiza, Miguel A. Basurto, Laura Castro, Adam Adamkowski and Waldemar Janicki VI Contents Chapter 8 Microfabricated Implantable Pressure Sensor for Flow Measurement 169 Sheng Liu, Reginald Farrow and Gordon Thomas    Preface  Flow measurement is a basic tool in industry, engineering and research. The existing applications reveal the evolution and development of new methods and devices through the years. Some of the latest emerging technologies, such as microelectronics and nanotechnology, have put forward new challenges in the flow measurement and are treated at the beginning of this book. This book comprises 8 chapters divided into 4 sections, starting with “microflows”, followed by the “biphasic” and “gas flow”. Fourth and the final section deals with the “indirect methods of flow measurement” involving two different applications. In particular, the first section revolves around the challenges in microflow measurements and the importance of studying their governing laws. Second section deals with the measurement of fluids composed of two phases through different methods, initially with the separation of the two phases accompanied by the measurement of the liquid film thickness and void fraction in the narrow gap by liquid film sensors and others methods. In third section, the flow of gases has been studied with the help of the proposed experimental setup for measuring the passage of air through a rotating disk. In another chapter, the same phenomenon has been studied using different other setups and devices. Fourth and final section includes two chapters describing the pressure measurement as an indirect method to calculate the flow. First chapter deals with the large volumes such as hydropower plants, and the second chapter presents the measurement of low flows by pressure microsensors. I would like to thank all the contributing authors in this book, besides the valuable cooperation of the co-editors Dr. Miguel A. Basurto Pensado and Dr. Laura L. Castro Gómez, for their meaningful help in the scientific review of some chapters published here. Special thanks to the kind attention of the publishing head Ms. Vana Persen. Dr. Gustavo Urquiza Beltrán and Dr. Laura L. Castro Gómez Research Center on Engineerging and Applied Science (CIICAp) from the Autonomous University of Morelos State (UAEM), Mexico . Challenges in Microflow Measurements 3 Boguslaw Kruczek and Siamak Lashkari Part 2 Biphasic Flow Measurement 37 Chapter 2 Gas-Liquid Two-Phase Flow Rate Measurements by Flow Division and Separation. of accurate measurement of microflows. The microflows in microfluidics are measured using both the CP and CV techniques. 3. Microflow measurement Indirect measurements of microflows may involve. given time, the primary measurement is based on an equation of state. For the level of accuracy of flow measurements the ideal gas law suffice: pV nRT (1) Flow Measurement 4 where,