Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels
As for two-phase flow in rectangular channels, the flow regimes especially like churn-turbulent and annular flow are significant for the physical problem like Countercurrent Flow Limitation (CCFL). In this study, the rectangular channels with cross-sections of 4 × 66 mm, 6 × 66 mm, 8 × 66 mm are ado...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2023-11-01
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| Series: | Nuclear Engineering and Technology |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S1738573323003273 |
| _version_ | 1797653717544075264 |
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| author | Qingche He Liang-ming Pan Luteng Zhang Wangtao Xu Meiyue Yan |
| author_facet | Qingche He Liang-ming Pan Luteng Zhang Wangtao Xu Meiyue Yan |
| author_sort | Qingche He |
| collection | DOAJ |
| description | As for two-phase flow in rectangular channels, the flow regimes especially like churn-turbulent and annular flow are significant for the physical problem like Countercurrent Flow Limitation (CCFL). In this study, the rectangular channels with cross-sections of 4 × 66 mm, 6 × 66 mm, 8 × 66 mm are adopted to investigate the flow regimes of air-water vertical upward two phase flow under adiabatic condition. The gas and liquid superficial velocities are 0≤jg≤20m/s and 0.25≤jf≤3m/s respectively which covering bubbly to annular flow. The flow regimes are identified by random forest algorithm and the flow regime maps are obtained. As the results, the transitional void fraction from slug to churn turbulent flow fluctuate from 0.47 to 0.58 which is significantly affected by the dimensional size of channel and flow rate. Besides, the void fraction at transitional points from churn-turbulent (slug) to annular flow are 0.66–0.67, which are independent with the gap size. Furthermore, a new criteria of slug to churn-turbulent flow is established in this study. In addition, by introducing the interfacial force model, the criteria of churn-turbulent (slug) flow to annular flow is verified. |
| first_indexed | 2024-03-11T16:48:39Z |
| format | Article |
| id | doaj.art-daeeba5623424f56adf2127e2a518fdf |
| institution | Directory Open Access Journal |
| issn | 1738-5733 |
| language | English |
| last_indexed | 2024-03-11T16:48:39Z |
| publishDate | 2023-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Nuclear Engineering and Technology |
| spelling | doaj.art-daeeba5623424f56adf2127e2a518fdf2023-10-22T04:48:27ZengElsevierNuclear Engineering and Technology1738-57332023-11-01551139733982Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channelsQingche He0Liang-ming Pan1Luteng Zhang2Wangtao Xu3Meiyue Yan4Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; Department of Nuclear Engineering and Technology, Chongqing University, Chongqing, 400044, ChinaKey Laboratory of Low-Grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; Department of Nuclear Engineering and Technology, Chongqing University, Chongqing, 400044, China; Guizhou Institute of Technology, 1st, Caiguan Road, Yunyan District, Guiyang City, Guizhou, 550003, PR China; Corresponding author. Chongqing University, No.174,Shazheng street, Shapingba district, Chongqing, 400044, PR China.Key Laboratory of Low-Grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; Department of Nuclear Engineering and Technology, Chongqing University, Chongqing, 400044, ChinaKey Laboratory of Low-Grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; Department of Nuclear Engineering and Technology, Chongqing University, Chongqing, 400044, ChinaKey Laboratory of Low-Grade Energy Utilization Technologies and Systems, Ministry of Education, Chongqing University, Chongqing, 400044, PR China; Department of Nuclear Engineering and Technology, Chongqing University, Chongqing, 400044, ChinaAs for two-phase flow in rectangular channels, the flow regimes especially like churn-turbulent and annular flow are significant for the physical problem like Countercurrent Flow Limitation (CCFL). In this study, the rectangular channels with cross-sections of 4 × 66 mm, 6 × 66 mm, 8 × 66 mm are adopted to investigate the flow regimes of air-water vertical upward two phase flow under adiabatic condition. The gas and liquid superficial velocities are 0≤jg≤20m/s and 0.25≤jf≤3m/s respectively which covering bubbly to annular flow. The flow regimes are identified by random forest algorithm and the flow regime maps are obtained. As the results, the transitional void fraction from slug to churn turbulent flow fluctuate from 0.47 to 0.58 which is significantly affected by the dimensional size of channel and flow rate. Besides, the void fraction at transitional points from churn-turbulent (slug) to annular flow are 0.66–0.67, which are independent with the gap size. Furthermore, a new criteria of slug to churn-turbulent flow is established in this study. In addition, by introducing the interfacial force model, the criteria of churn-turbulent (slug) flow to annular flow is verified.http://www.sciencedirect.com/science/article/pii/S1738573323003273Rectangular channelTwo phase flowFlow regime mapRegime transition |
| spellingShingle | Qingche He Liang-ming Pan Luteng Zhang Wangtao Xu Meiyue Yan Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels Nuclear Engineering and Technology Rectangular channel Two phase flow Flow regime map Regime transition |
| title | Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels |
| title_full | Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels |
| title_fullStr | Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels |
| title_full_unstemmed | Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels |
| title_short | Experimental research on flow regime and transitional criterion of slug to churn-turbulent and churn-turbulent to annular flow in rectangular channels |
| title_sort | experimental research on flow regime and transitional criterion of slug to churn turbulent and churn turbulent to annular flow in rectangular channels |
| topic | Rectangular channel Two phase flow Flow regime map Regime transition |
| url | http://www.sciencedirect.com/science/article/pii/S1738573323003273 |
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