Falling film thickness measurement using air-coupled ultrasonic transducer
| Autor: | Annamalai Mani, Akhil Balachandran, Arjun Jayakumar, Krishnan Balasubramaniam |
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| Rok vydání: | 2019 |
| Předmět: |
Fluid Flow and Transfer Processes
Materials science Mechanical Engineering General Chemical Engineering Acoustics Aerospace Engineering Reynolds number Ranging 02 engineering and technology 01 natural sciences 010305 fluids & plasmas Volumetric flow rate symbols.namesake Transducer 020401 chemical engineering Nuclear Energy and Engineering 0103 physical sciences symbols Ultrasonic sensor Tube (fluid conveyance) 0204 chemical engineering Falling (sensation) Sensitivity (electronics) |
| Zdroj: | Experimental Thermal and Fluid Science. 109:109906 |
| ISSN: | 0894-1777 |
| DOI: | 10.1016/j.expthermflusci.2019.109906 |
| Popis: | In this work, a new, non-intrusive, increased sensitivity technique based on air-coupled ultrasonics was developed to measure the falling liquid film thickness. Air-coupled transducer of frequency 1 MHz was used to make static and dynamic measurements of water level/film thickness. The air-coupled method were compared with a metal-side contact ultrasonic approach as well as calculating water levels in the collection tank. The falling film thickness measurement over inclined plate was used in this study. Measurement of film thickness was taken at flow rates in the range of 0.34–0.9 lpm. Relatively good agreement was found between the readings, which validates the dynamic measurement capability of the new technique. The technique was applied to measure the horizontal tube falling film thickness for falling film Reynolds number ranging from 130 to 350, at different circumferential angles ranging from 40° to 130° and at tube spacing of 5 mm and 15 mm. Measurements were compared with correlations available in the literature and found to be in good agreement. |
| Databáze: | OpenAIRE |
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