Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump
The flow in the vertical long-axis fire pump exhibits complex, three-dimensional, unsteady flow features. In an attempt to understand the effects of turbulence models on the flow mechanism and performance characteristics of the pump, the ANSYS CFX software was used to carry out numerical studies on...
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| Format: | Article |
| Language: | English |
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Isfahan University of Technology
2022-09-01
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| Series: | Journal of Applied Fluid Mechanics |
| Subjects: | |
| Online Access: | https://www.jafmonline.net/article_2094_284b163500e3f74fd1334b66bf6a8c1b.pdf |
| _version_ | 1811209371896512512 |
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| author | F. K. Osman J. Zhang L. Lai A. A. Kwarteng |
| author_facet | F. K. Osman J. Zhang L. Lai A. A. Kwarteng |
| author_sort | F. K. Osman |
| collection | DOAJ |
| description | The flow in the vertical long-axis fire pump exhibits complex, three-dimensional, unsteady flow features. In an attempt to understand the effects of turbulence models on the flow mechanism and performance characteristics of the pump, the ANSYS CFX software was used to carry out numerical studies on the vertical fire pump using URANS. The main objective of this study was to investigate the unsteady flow dynamics within the vertical fire pump and the influence of applying different computational turbulence models. The study then sought to conduct a brief analysis of the unsteady pressure pulsation characteristics of the pump. The reliability of the CFD model was validated with an external characteristic test. The transient pressure distribution, velocity field and external characteristics were analyzed. The results were compared to experimental results, where it was revealed that the SST k-ω model showed 1.82% and 0.81% improvements in efficiency and head, respectively, over the k-ε models. In terms of the power performance, however, the standard k-ε is less likely to over-predict the power used by the pump in overload conditions as compared to the other turbulence models. The pressure charts did not show significant reactions to varying turbulence models across all the studied flow rates. However, the velocity streamlines revealed that there were several disruptions in streamwise flow, where both the standard and RNG k-ε models exhibited more recirculation areas than the SST k-ω and standard k-ω models. Overall, for this type of application, SST k-ω was the best-performing turbulence model, while RNG k-ε showed the poorest performance. Nonetheless, the RNG k-ε also has its strengths. This investigation would serve as a theoretical reference for further research and development in fluid machinery. |
| first_indexed | 2024-04-12T04:38:20Z |
| format | Article |
| id | doaj.art-d0a03d4e646344868dd2b5a20960523f |
| institution | Directory Open Access Journal |
| issn | 1735-3572 1735-3645 |
| language | English |
| last_indexed | 2024-04-12T04:38:20Z |
| publishDate | 2022-09-01 |
| publisher | Isfahan University of Technology |
| record_format | Article |
| series | Journal of Applied Fluid Mechanics |
| spelling | doaj.art-d0a03d4e646344868dd2b5a20960523f2022-12-22T03:47:44ZengIsfahan University of TechnologyJournal of Applied Fluid Mechanics1735-35721735-36452022-09-011561661167410.47176/jafm.15.06.13032094Effects of Turbulence Models on Flow Characteristics of a Vertical Fire PumpF. K. Osman0J. Zhang1L. Lai2A. A. Kwarteng3National Research Center of Pumps, Jiangsu University, Zhenjiang, 212013, ChinaNational Research Center of Pumps, Jiangsu University, Zhenjiang, 212013, ChinaNational Research Center of Pumps, Jiangsu University, Zhenjiang, 212013, ChinaDepartment of Mechanical Engineering, University of Mines and Technology, Tarkwa, GhanaThe flow in the vertical long-axis fire pump exhibits complex, three-dimensional, unsteady flow features. In an attempt to understand the effects of turbulence models on the flow mechanism and performance characteristics of the pump, the ANSYS CFX software was used to carry out numerical studies on the vertical fire pump using URANS. The main objective of this study was to investigate the unsteady flow dynamics within the vertical fire pump and the influence of applying different computational turbulence models. The study then sought to conduct a brief analysis of the unsteady pressure pulsation characteristics of the pump. The reliability of the CFD model was validated with an external characteristic test. The transient pressure distribution, velocity field and external characteristics were analyzed. The results were compared to experimental results, where it was revealed that the SST k-ω model showed 1.82% and 0.81% improvements in efficiency and head, respectively, over the k-ε models. In terms of the power performance, however, the standard k-ε is less likely to over-predict the power used by the pump in overload conditions as compared to the other turbulence models. The pressure charts did not show significant reactions to varying turbulence models across all the studied flow rates. However, the velocity streamlines revealed that there were several disruptions in streamwise flow, where both the standard and RNG k-ε models exhibited more recirculation areas than the SST k-ω and standard k-ω models. Overall, for this type of application, SST k-ω was the best-performing turbulence model, while RNG k-ε showed the poorest performance. Nonetheless, the RNG k-ε also has its strengths. This investigation would serve as a theoretical reference for further research and development in fluid machinery.https://www.jafmonline.net/article_2094_284b163500e3f74fd1334b66bf6a8c1b.pdfvertical fire pumpnumerical simulationcfdturbulence modelsst k-ω |
| spellingShingle | F. K. Osman J. Zhang L. Lai A. A. Kwarteng Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump Journal of Applied Fluid Mechanics vertical fire pump numerical simulation cfd turbulence model sst k-ω |
| title | Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump |
| title_full | Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump |
| title_fullStr | Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump |
| title_full_unstemmed | Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump |
| title_short | Effects of Turbulence Models on Flow Characteristics of a Vertical Fire Pump |
| title_sort | effects of turbulence models on flow characteristics of a vertical fire pump |
| topic | vertical fire pump numerical simulation cfd turbulence model sst k-ω |
| url | https://www.jafmonline.net/article_2094_284b163500e3f74fd1334b66bf6a8c1b.pdf |
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