{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,16]],"date-time":"2025-10-16T20:30:43Z","timestamp":1760646643148,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2017,5,8]],"date-time":"2017-05-08T00:00:00Z","timestamp":1494201600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2016M2B2A9911742","NRF-2010-0020077"],"award-info":[{"award-number":["NRF-2016M2B2A9911742","NRF-2010-0020077"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this study, a new and improved electrical conductance sensor is proposed for application not only to a horizontal pipe, but also an inclined one. The conductance sensor was designed to have a dual layer, each consisting of a three-electrode set to obtain two instantaneous conductance signals in turns, so that the area-averaged void fraction and structure velocity could be measured simultaneously. The optimum configuration of the electrodes was determined through numerical analysis, and the calibration curves for stratified and annular flow were obtained through a series of static experiments. The fabricated conductance sensor was applied to a 45 mm inner diameter U-shaped downward inclined pipe with an inclination angle of 3\u00b0 under adiabatic air-water flow conditions. In the tests, the superficial velocities ranged from 0.1 to 3.0 m\/s for water and from 0.1 to 18 m\/s for air. The obtained mean void fraction and the structure velocity from the conductance sensor were validated against the measurement by the wire-mesh sensor and the cross-correlation technique for the visualized images, respectively. The results of the flow regime classification and the corresponding time series of the void fraction at a variety of flow velocities were also discussed.<\/jats:p>","DOI":"10.3390\/s17051063","type":"journal-article","created":{"date-parts":[[2017,5,8]],"date-time":"2017-05-08T11:45:16Z","timestamp":1494243916000},"page":"1063","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Dual Conductance Sensor for Simultaneous Measurement of Void Fraction and Structure Velocity of Downward Two-Phase Flow in a Slightly Inclined Pipe"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6023-1589","authenticated-orcid":false,"given":"Yeon-Gun","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Nuclear and Energy Engineering, Jeju National University, Jeju 63243, Korea"}]},{"given":"Woo-Youn","family":"Won","sequence":"additional","affiliation":[{"name":"Department of Nuclear and Energy Engineering, Jeju National University, Jeju 63243, Korea"}]},{"given":"Bo-An","family":"Lee","sequence":"additional","affiliation":[{"name":"Institute for Nuclear Science and Technology, Jeju National University, Jeju 63243, Korea"}]},{"given":"Sin","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Energy Systems Engineering, Chung-Ang University, Seoul 06974, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2017,5,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"777","DOI":"10.1016\/0301-9322(88)90074-2","article-title":"An impedance method for the measurement of liquid hold-up in two-phase flow","volume":"14","author":"Andreussi","year":"1988","journal-title":"Int. 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