PIV and CFD investigation of flocculation hydrodynamics. (c2019)
The performance of paddle flocculators in water treatment is highly influenced by the basin hydrodynamics. In their design, several hydrodynamic and geometric parameters are required to ensure the efficiency of the process. Amongst these parameters, the slippage factor k is estimated to fall in the...
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| Format: | masterThesis |
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2019
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| Online Access: | http://hdl.handle.net/10725/11577 https://doi.org/10.26756/th.2019.143 http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.php |
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| _version_ | 1864513489231413248 |
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| author | Danageuzian, Hrair Razmig |
| author_facet | Danageuzian, Hrair Razmig |
| author_role | author |
| dc.creator.none.fl_str_mv | Danageuzian, Hrair Razmig |
| dc.date.none.fl_str_mv | 2019-11-25T11:38:52Z 2019-11-25T11:38:52Z 2019 2019-11-25 2019-05-17 |
| dc.identifier.none.fl_str_mv | http://hdl.handle.net/10725/11577 https://doi.org/10.26756/th.2019.143 http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.php |
| dc.language.none.fl_str_mv | en |
| dc.publisher.none.fl_str_mv | Lebanese American University |
| dc.rights.*.fl_str_mv | info:eu-repo/semantics/openAccess |
| dc.subject.none.fl_str_mv | Lebanese American University -- Dissertations Dissertations, Academic Water -- Purification -- Flocculation Particle image velocimetry Water waves Fluid dynamics |
| dc.title.none.fl_str_mv | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| dc.type.none.fl_str_mv | Thesis info:eu-repo/semantics/publishedVersion info:eu-repo/semantics/masterThesis |
| description | The performance of paddle flocculators in water treatment is highly influenced by the basin hydrodynamics. In their design, several hydrodynamic and geometric parameters are required to ensure the efficiency of the process. Amongst these parameters, the slippage factor k is estimated to fall in the range of 0.2 to 0.3. An existing lack of the quantitative understanding of the velocity flow field in such flocculators is evidently identified in the literature. This research investigates the velocity field of turbulent flow in a paddle flocculator, and its influence on the process performance by quantifying k at low rotational speeds of 3 rpm and 4 rpm. A laboratory scale paddle flocculator was designed and experimentally investigated using particle image velocimetry measurements. Time averaged velocity data of the flow field at a plane perpendicular to the paddle wheel revealed the velocity of water particles surrounding the blades. Numerical simulations using a commercial computational fluid dynamics software package, ANSYS, were generated for the laboratory scale paddle flocculator. The influences of mesh structure and turbulence models SST k–ω and IDDES were evaluated. As a result, a good correlation between the PIV and CFD results was verified through a Goodness-of-Fit evaluation (with a coefficient of determination almost equal to 0.9). Results showed that the SST k–ω model can accurately predict the flocculation flow when the more computationally expensive IDDES model is not feasible. The slippage factor k was quantified as 0.18 for both rotational speeds. This indicates that more power is imparted to the water body than estimated in most design procedures, thus yielding higher velocity gradient values for flocculation in the basin. It is expected that the application of the validated CFD model will help improve the design and optimization of paddle flocculators. |
| eu_rights_str_mv | openAccess |
| format | masterThesis |
| id | LAURepo_e9d6f46948477c8b5a0f5177c052d253 |
| language_invalid_str_mv | en |
| network_acronym_str | LAURepo |
| network_name_str | Lebanese American University repository |
| oai_identifier_str | oai:laur.lau.edu.lb:10725/11577 |
| publishDate | 2019 |
| publisher.none.fl_str_mv | Lebanese American University |
| repository.mail.fl_str_mv | |
| repository.name.fl_str_mv | |
| repository_id_str | |
| spelling | PIV and CFD investigation of flocculation hydrodynamics. (c2019)Danageuzian, Hrair RazmigLebanese American University -- DissertationsDissertations, AcademicWater -- Purification -- FlocculationParticle image velocimetryWater wavesFluid dynamicsThe performance of paddle flocculators in water treatment is highly influenced by the basin hydrodynamics. In their design, several hydrodynamic and geometric parameters are required to ensure the efficiency of the process. Amongst these parameters, the slippage factor k is estimated to fall in the range of 0.2 to 0.3. An existing lack of the quantitative understanding of the velocity flow field in such flocculators is evidently identified in the literature. This research investigates the velocity field of turbulent flow in a paddle flocculator, and its influence on the process performance by quantifying k at low rotational speeds of 3 rpm and 4 rpm. A laboratory scale paddle flocculator was designed and experimentally investigated using particle image velocimetry measurements. Time averaged velocity data of the flow field at a plane perpendicular to the paddle wheel revealed the velocity of water particles surrounding the blades. Numerical simulations using a commercial computational fluid dynamics software package, ANSYS, were generated for the laboratory scale paddle flocculator. The influences of mesh structure and turbulence models SST k–ω and IDDES were evaluated. As a result, a good correlation between the PIV and CFD results was verified through a Goodness-of-Fit evaluation (with a coefficient of determination almost equal to 0.9). Results showed that the SST k–ω model can accurately predict the flocculation flow when the more computationally expensive IDDES model is not feasible. The slippage factor k was quantified as 0.18 for both rotational speeds. This indicates that more power is imparted to the water body than estimated in most design procedures, thus yielding higher velocity gradient values for flocculation in the basin. It is expected that the application of the validated CFD model will help improve the design and optimization of paddle flocculators.24M1 hard copy: xvi, 128 leaves: col. ill.; 30 cm. available at RNL.Bibliography: (leaves 113-115).Lebanese American University2019-11-25T11:38:52Z2019-11-25T11:38:52Z20192019-11-252019-05-17Thesisinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesishttp://hdl.handle.net/10725/11577https://doi.org/10.26756/th.2019.143http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.phpeninfo:eu-repo/semantics/openAccessoai:laur.lau.edu.lb:10725/115772021-03-19T10:47:38Z |
| spellingShingle | PIV and CFD investigation of flocculation hydrodynamics. (c2019) Danageuzian, Hrair Razmig Lebanese American University -- Dissertations Dissertations, Academic Water -- Purification -- Flocculation Particle image velocimetry Water waves Fluid dynamics |
| status_str | publishedVersion |
| title | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| title_full | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| title_fullStr | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| title_full_unstemmed | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| title_short | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| title_sort | PIV and CFD investigation of flocculation hydrodynamics. (c2019) |
| topic | Lebanese American University -- Dissertations Dissertations, Academic Water -- Purification -- Flocculation Particle image velocimetry Water waves Fluid dynamics |
| url | http://hdl.handle.net/10725/11577 https://doi.org/10.26756/th.2019.143 http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.php |