Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit
Vibration and fatigue damage of pump shafts has become a prominent engineering problem, indicating the need for higher-quality reliability analysis of the pump unit in the design stage. In this study, the unsteady flow field in a large centrifugal dredge pump was numerically simulated via the unstea...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Isfahan University of Technology
2023-03-01
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| Series: | Journal of Applied Fluid Mechanics |
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| Online Access: | https://www.jafmonline.net/article_2197_ea180cfa8795352174507eb1084fc5dc.pdf |
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| author | L. Cao T. Wu T. Guo J. Hu J. Cao |
| author_facet | L. Cao T. Wu T. Guo J. Hu J. Cao |
| author_sort | L. Cao |
| collection | DOAJ |
| description | Vibration and fatigue damage of pump shafts has become a prominent engineering problem, indicating the need for higher-quality reliability analysis of the pump unit in the design stage. In this study, the unsteady flow field in a large centrifugal dredge pump was numerically simulated via the unsteady Reynolds-averaged Navier-Stokes (URANS) method with the SST k-ω model. An experiment was carried out to verify the numerical method. The hydraulic radial force on the impeller and the total radial load were calculated based on computational fluid dynamics. The flow field with a double volute was simulated, analyzed, and compared to the flow field with a single volute. The stress of the pump shaft caused by the radial load was also calculated and discussed. The results show that the impeller gravity determines the time-averaged value and fluctuation frequency of the total radial load on the shaft, which must be considered in the shaft stability analysis. The total radial load fluctuating in asymmetric cycle results in stress cycles with different features at different circumferential locations. The application of a double volute effectively reduces the radial load on the pump shaft, which decreases the time-averaged hydraulic radial force by 38% and its fluctuation amplitude by 3%, decreases the time-averaged total radial load by 20% and its fluctuation amplitude by 28% in the design condition, and decreases the local stress at the narrowest shaft section by 44%. A double volute can be applied to weaken vibration and fatigue damage for a pump shaft if it is acceptable for the pump efficiency to be lowered. |
| first_indexed | 2024-04-10T05:48:45Z |
| format | Article |
| id | doaj.art-89f29461baca42918ba7537b91a4f707 |
| institution | Directory Open Access Journal |
| issn | 1735-3572 1735-3645 |
| language | English |
| last_indexed | 2024-04-10T05:48:45Z |
| publishDate | 2023-03-01 |
| publisher | Isfahan University of Technology |
| record_format | Article |
| series | Journal of Applied Fluid Mechanics |
| spelling | doaj.art-89f29461baca42918ba7537b91a4f7072023-03-05T06:16:40ZengIsfahan University of TechnologyJournal of Applied Fluid Mechanics1735-35721735-36452023-03-011651005101610.47176/jafm.16.05.16462197Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump UnitL. Cao0T. Wu1T. Guo2J. Hu3J. Cao4CCCC National Engineering Research Center of Dredging Technology and Equipment Co., Ltd., Shanghai, 200082, ChinaCCCC National Engineering Research Center of Dredging Technology and Equipment Co., Ltd., Shanghai, 200082, ChinaCCCC National Engineering Research Center of Dredging Technology and Equipment Co., Ltd., Shanghai, 200082, ChinaCCCC National Engineering Research Center of Dredging Technology and Equipment Co., Ltd., Shanghai, 200082, ChinaState Key Laboratory of Hydroscience and Engineering & Department of Energy and Power Engineering, Tsinghua University, Beijing, 100084, ChinaVibration and fatigue damage of pump shafts has become a prominent engineering problem, indicating the need for higher-quality reliability analysis of the pump unit in the design stage. In this study, the unsteady flow field in a large centrifugal dredge pump was numerically simulated via the unsteady Reynolds-averaged Navier-Stokes (URANS) method with the SST k-ω model. An experiment was carried out to verify the numerical method. The hydraulic radial force on the impeller and the total radial load were calculated based on computational fluid dynamics. The flow field with a double volute was simulated, analyzed, and compared to the flow field with a single volute. The stress of the pump shaft caused by the radial load was also calculated and discussed. The results show that the impeller gravity determines the time-averaged value and fluctuation frequency of the total radial load on the shaft, which must be considered in the shaft stability analysis. The total radial load fluctuating in asymmetric cycle results in stress cycles with different features at different circumferential locations. The application of a double volute effectively reduces the radial load on the pump shaft, which decreases the time-averaged hydraulic radial force by 38% and its fluctuation amplitude by 3%, decreases the time-averaged total radial load by 20% and its fluctuation amplitude by 28% in the design condition, and decreases the local stress at the narrowest shaft section by 44%. A double volute can be applied to weaken vibration and fatigue damage for a pump shaft if it is acceptable for the pump efficiency to be lowered.https://www.jafmonline.net/article_2197_ea180cfa8795352174507eb1084fc5dc.pdfcentrifugal dredge pumpradial forcegravityshaftdynamic stressdouble volute |
| spellingShingle | L. Cao T. Wu T. Guo J. Hu J. Cao Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit Journal of Applied Fluid Mechanics centrifugal dredge pump radial force gravity shaft dynamic stress double volute |
| title | Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit |
| title_full | Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit |
| title_fullStr | Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit |
| title_full_unstemmed | Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit |
| title_short | Numerical Analysis on the Unsteady Radial Load on the Shaft of a Large-Scale Dredge Pump Unit |
| title_sort | numerical analysis on the unsteady radial load on the shaft of a large scale dredge pump unit |
| topic | centrifugal dredge pump radial force gravity shaft dynamic stress double volute |
| url | https://www.jafmonline.net/article_2197_ea180cfa8795352174507eb1084fc5dc.pdf |
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