Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes
Experimental investigations were conducted to study the effect of micro-bubbles injected into water flowing through straight and helical pipes with different curvature ( 0.025, 0.05 and 0.1). The micro-bubbles were produced using two hydrocyclone micro-bubble generators positioned face to face with...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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The Japan Society of Mechanical Engineers
2009-03-01
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| Series: | Journal of Fluid Science and Technology |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/jfst/4/1/4_1_156/_pdf/-char/en |
| _version_ | 1819364505347424256 |
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| author | Mohammed M. E. SHATAT Shinichiro YANASE Toshihiro TAKAMI Toru HYAKUTAKE |
| author_facet | Mohammed M. E. SHATAT Shinichiro YANASE Toshihiro TAKAMI Toru HYAKUTAKE |
| author_sort | Mohammed M. E. SHATAT |
| collection | DOAJ |
| description | Experimental investigations were conducted to study the effect of micro-bubbles injected into water flowing through straight and helical pipes with different curvature ( 0.025, 0.05 and 0.1). The micro-bubbles were produced using two hydrocyclone micro-bubble generators positioned face to face with opposite direction of swirl flow. The mean diameter of the micro-bubbles generated was about 60μ m, while the maximum diameter observed was 174μ m, with air fraction, which will be defined in Eq.(4), ranging from 0.21% to 0.44%. The effect of the Reynolds number on the drag reduction is also presented. The experimental results show that, the micro-bubble has an effect of drag reduction on both straight and helical pipes, though the drag reduction in a straight pipe is much higher than that in a helical pipe, because of the secondary flow in a helical pipe. It is found that the drag reduction increases with the decrease of curvature and the increase of air fraction. The maximum value of drag reduction ratio was 51% in case of a straight pipe, while that for a helical pipe was 16%. |
| first_indexed | 2024-12-24T23:00:00Z |
| format | Article |
| id | doaj.art-dc884e6c1e7d44c5ac4e5324303ce1b8 |
| institution | Directory Open Access Journal |
| issn | 1880-5558 |
| language | English |
| last_indexed | 2024-12-24T23:00:00Z |
| publishDate | 2009-03-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Journal of Fluid Science and Technology |
| spelling | doaj.art-dc884e6c1e7d44c5ac4e5324303ce1b82022-12-21T16:35:09ZengThe Japan Society of Mechanical EngineersJournal of Fluid Science and Technology1880-55582009-03-014115616710.1299/jfst.4.156jfstDrag Reduction Effects of Micro-Bubbles in Straight and Helical PipesMohammed M. E. SHATAT0Shinichiro YANASE1Toshihiro TAKAMI2Toru HYAKUTAKE3Graduate School of Natural Science and Technology, Okayama UniversityGraduate School of Natural Science and Technology, Okayama UniversityDepartment of Mechanical Engineering, Okayama University of ScienceGraduate School of Natural Science and Technology, Okayama UniversityExperimental investigations were conducted to study the effect of micro-bubbles injected into water flowing through straight and helical pipes with different curvature ( 0.025, 0.05 and 0.1). The micro-bubbles were produced using two hydrocyclone micro-bubble generators positioned face to face with opposite direction of swirl flow. The mean diameter of the micro-bubbles generated was about 60μ m, while the maximum diameter observed was 174μ m, with air fraction, which will be defined in Eq.(4), ranging from 0.21% to 0.44%. The effect of the Reynolds number on the drag reduction is also presented. The experimental results show that, the micro-bubble has an effect of drag reduction on both straight and helical pipes, though the drag reduction in a straight pipe is much higher than that in a helical pipe, because of the secondary flow in a helical pipe. It is found that the drag reduction increases with the decrease of curvature and the increase of air fraction. The maximum value of drag reduction ratio was 51% in case of a straight pipe, while that for a helical pipe was 16%.https://www.jstage.jst.go.jp/article/jfst/4/1/4_1_156/_pdf/-char/enpipe flowsecondary flowpressure dropdrag reductionmicro-bubblecurved pipevoid fraction |
| spellingShingle | Mohammed M. E. SHATAT Shinichiro YANASE Toshihiro TAKAMI Toru HYAKUTAKE Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes Journal of Fluid Science and Technology pipe flow secondary flow pressure drop drag reduction micro-bubble curved pipe void fraction |
| title | Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes |
| title_full | Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes |
| title_fullStr | Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes |
| title_full_unstemmed | Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes |
| title_short | Drag Reduction Effects of Micro-Bubbles in Straight and Helical Pipes |
| title_sort | drag reduction effects of micro bubbles in straight and helical pipes |
| topic | pipe flow secondary flow pressure drop drag reduction micro-bubble curved pipe void fraction |
| url | https://www.jstage.jst.go.jp/article/jfst/4/1/4_1_156/_pdf/-char/en |
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