RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine

Nowadays, the global energy crisis has encouraged the use of alternative sources like the energy available in the water currents of seas and rivers. The vertical axis water turbine (VAWT) is an interesting option to harness this energy due to its advantages of facile installation, maintenance and op...

Full description

Autores:
Laín Beatove, Santiago
Lopez Mejia, Omar D
Quiñones, Jhon J.
Tipo de recurso:
Article of journal
Fecha de publicación:
2018
Institución:
Universidad Autónoma de Occidente
Repositorio:
RED: Repositorio Educativo Digital UAO
Idioma:
eng
OAI Identifier:
oai:red.uao.edu.co:10614/11390
Acceso en línea:
http://hdl.handle.net/10614/11390
https://doi.org/10.1016/j.powtec.2018.03.026
Palabra clave:
Hydraulic turbines
Turbinas hidráulicas
Aerodynamics
Aerodinámica
Darrieus turbine
Delayed Detached Eddy Simulation
Detached Eddy Simulation
Vertical axis water turbine
Computational Fluid Dynamics
Hybrid RANS-LES models
Rights
openAccess
License
Derechos Reservados - Universidad Autónoma de Occidente
id REPOUAO2_c5b72aa370442e687203f3ef124a9ad3
oai_identifier_str oai:red.uao.edu.co:10614/11390
network_acronym_str REPOUAO2
network_name_str RED: Repositorio Educativo Digital UAO
repository_id_str
dc.title.eng.fl_str_mv RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
title RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
spellingShingle RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
Hydraulic turbines
Turbinas hidráulicas
Aerodynamics
Aerodinámica
Darrieus turbine
Delayed Detached Eddy Simulation
Detached Eddy Simulation
Vertical axis water turbine
Computational Fluid Dynamics
Hybrid RANS-LES models
title_short RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
title_full RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
title_fullStr RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
title_full_unstemmed RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
title_sort RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine
dc.creator.fl_str_mv Laín Beatove, Santiago
Lopez Mejia, Omar D
Quiñones, Jhon J.
dc.contributor.author.none.fl_str_mv Laín Beatove, Santiago
Lopez Mejia, Omar D
Quiñones, Jhon J.
dc.subject.lemb.eng.fl_str_mv Hydraulic turbines
topic Hydraulic turbines
Turbinas hidráulicas
Aerodynamics
Aerodinámica
Darrieus turbine
Delayed Detached Eddy Simulation
Detached Eddy Simulation
Vertical axis water turbine
Computational Fluid Dynamics
Hybrid RANS-LES models
dc.subject.lemb.spa.fl_str_mv Turbinas hidráulicas
dc.subject.armarc.eng.fl_str_mv Aerodynamics
dc.subject.armarc.spa.fl_str_mv Aerodinámica
dc.subject.proposal.eng.fl_str_mv Darrieus turbine
Delayed Detached Eddy Simulation
Detached Eddy Simulation
Vertical axis water turbine
Computational Fluid Dynamics
Hybrid RANS-LES models
description Nowadays, the global energy crisis has encouraged the use of alternative sources like the energy available in the water currents of seas and rivers. The vertical axis water turbine (VAWT) is an interesting option to harness this energy due to its advantages of facile installation, maintenance and operation. However, it is known that its efficiency is lower than that of other types of turbines due to the unsteady effects present in its flow physics. This work aims to analyse through Computational Fluid Dynamics (CFD) the turbulent flow dynamics around a small scale VAWT confined in a hydrodynamic tunnel. The simulations were developed using the Unsteady Reynolds Averaged Navier Stokes (URANS), Detached Eddy Simulation (DES) and Delayed Detached Eddy Simulation (DDES) turbulence models, all of them based on k-ω Shear Stress Transport (SST). The results and analysis of the simulations are presented, illustrating the influence of the tip speed ratio. The numerical results of the URANS model show a similar behaviour with respect to the experimental power curve of the turbine using a lower number of elements than those used in the DES and DDES models. Finally, with the help of both the Q-criterion and field contours it is observed that the refinements made in the mesh adaptation process for the DES and DDES models improve the identification of the scales of the vorticity structures and the flow phenomena present on the near and far wake of the turbine
publishDate 2018
dc.date.issued.none.fl_str_mv 2018-09-06
dc.date.accessioned.none.fl_str_mv 2019-11-01T20:57:47Z
dc.date.available.none.fl_str_mv 2019-11-01T20:57:47Z
dc.type.spa.fl_str_mv Artículo de revista
dc.type.coar.fl_str_mv http://purl.org/coar/resource_type/c_2df8fbb1
dc.type.coarversion.fl_str_mv http://purl.org/coar/version/c_970fb48d4fbd8a85
dc.type.coar.eng.fl_str_mv http://purl.org/coar/resource_type/c_6501
dc.type.content.eng.fl_str_mv Text
dc.type.driver.eng.fl_str_mv info:eu-repo/semantics/article
dc.type.redcol.eng.fl_str_mv http://purl.org/redcol/resource_type/ARTREF
dc.type.version.eng.fl_str_mv info:eu-repo/semantics/publishedVersion
format http://purl.org/coar/resource_type/c_6501
status_str publishedVersion
dc.identifier.issn.spa.fl_str_mv 1996-1073 (en línea)
dc.identifier.uri.none.fl_str_mv http://hdl.handle.net/10614/11390
dc.identifier.doi.spa.fl_str_mv https://doi.org/10.1016/j.powtec.2018.03.026
identifier_str_mv 1996-1073 (en línea)
url http://hdl.handle.net/10614/11390
https://doi.org/10.1016/j.powtec.2018.03.026
dc.language.iso.eng.fl_str_mv eng
language eng
dc.relation.citationissue.none.fl_str_mv 2348
dc.relation.citationvolume.none.fl_str_mv 11
dc.relation.cites.eng.fl_str_mv Mejia, O., Quiñones, J., & Laín, S. (2018). RANS and Hybrid RANS-LES Simulations of an H-Type Darrieus Vertical Axis Water Turbine. Energies, 11(9), 2348
dc.relation.ispartofjournal.eng.fl_str_mv Energies
dc.relation.references.none.fl_str_mv 1. Hall, T.J. Numerical Simulation of a Cross Flow Marine Hydrokinetic Turbine. Master’s Thesis, University of Washigton, Seattle,WA, USA, 2012.
2. Antheaume, S.; Maitre, T.; Achard, J. Hydraulic darrieus turbines efficiency for free fluid flow conditions versus power farms conditions. Renew. Energies 2008, 33, 2186–2198. [CrossRef]
3. Dai, Y.M.; Lam,W. Numerical Study of Straight-bladed Darrieus-type Tidal Turbine. ICE Energy 2009, 162, 67–76. [CrossRef]
4. Lain, S.; Osorio, C. Simulation and Evaluation of a Straight-bladed Darrieus-type Cross Flow Marine Turbine. J. Sci. Ind. Res. (JSIR) 2010, 69, 906–912.
5. Nabavi, Y. Numerical Study of the Ducted Shape Effect on the Performance of a Ducted Vertical Axis Tidal Turbine. Master’s Thesis, The University of British Columbia, Vancouver, BC, Canada, 2008.
6. Rawlings, G.W. Parametric Characterization of an Experimental Vertical Axis Hydro Turbine. Master’s Thesis, The University of British Columbia, Vancouver, BC, Canada, 2008.
7. Ferreira, C.J.; Bijl, H.; van Bussel, G.; van Kuik, G. Simulating Dynamic Stall in a 2D VAWT: Modeling Strategy, Verification and Validation with Particle Image Velocimetry Data. J. Phys. Conf. Ser. 2007, 75, 012023. [CrossRef]
8. Lei, H.; Zhou, D.; Bao, Y.; Li, Y.; Han, Z. Three-dimensional Improved Delayed Detached Eddy Simulation of a two-bladed vertical axis wind turbine. Energy Convers. Manag. 2017, 133, 235–248. [CrossRef]
9. Maître, T.; Amet, E.; Pellone, C. Modeling of the Flow in a DarrieusWater Turbine: Wall Grid Refinement Analysis and Comparison with Experiments. Renew. Energy 2013, 51, 497–512. [CrossRef]
10. Marsh, P.; Ranmuthugala, D.; Penesis, I.; Thomas, G. Three Dimensional Numerical Simulations of a Straight-Bladed Vertical Axis Tidal Turbine. In Proceedings of the 18th Australasian Fluid Mechanics Conference, Launceston, Australia, 3–7 December 2012.
11. Pellone, C.; Maître, T.; Amet, E. 3D RANS Modeling of a Cross Flow Water Turbine. In Proceedings of the SimHydro: New Trends in Simulation Hydroinformatics and 3D modeling, Nice, France, 12–14 September 2012.
12. Amet, E. Simulation Numerique d’une Hydrolienne à Axe Vertical de Type Darrieus. Ph.D. Thesis, Institut Polytechnique Grenoble, Grenoble, France, 2009.
13. Eca, L.; Hoekstra, M. A Verification Exercise for Two 2-D Steady Incompressible Turbulent Flows. In Proceedings of the ECCOMAS European Congress on Computational Methods in Applied Sciences and Engineering, Jyväskylä, Finland, 24–28 July 2004.
14. Spalart, P.R.; Jou,W.-H.; Strelets,M.; Allmaras, S. Comments on the Feasibility of LES forWings, and on a Hybrid RANS/LES Approach. In Proceedings of the Advances in DNS/LES, Ruston, LA, USA, 4–8 August 1997.
15. Shur, M.; Spalart, P.R.; Strelets, M.; Travin, A. Detached-eddy simulation of an airfoil at high angle of attack. In Proceedings of the Engineering TurbulenceModelling and Experiments-4, Corsica, France, 24–26May 1999.
16. Spalart, P.R. Young-Person’s Guide to Detached-Eddy Simulation Grids; NASA/CR-2001-211032; NASA Langley Research Center: Hampton, VA, USA, 2001.
17. Bussiere, M. The Experimental Investigation of Vortex Wakes from Oscillating Airfoils. Master’s Thesis, University of Alberta, Edmonton, AB, Canada, 2012.
18. Gorle, J.M.; Chatellier, L.; Pons, F.; Ba, M. Flow and Performance analysis of H-Darrieus hydro turbine in a confined flow: A computational and experimental study. J. Fluids Struct. 2016, 66, 382–402. [CrossRef]
19. Marsh, P.; Ranmuthugala, D.; Penesis, I.; Thomas, G. Three-dimensional Numerical Simulations of a Straight-Bladed Vertical Axis Tidal Turbine Investigating Power Output, Torque Ripple and Mounting Forces. Renew. Energy 2015, 83, 67–77. [CrossRef]
dc.rights.spa.fl_str_mv Derechos Reservados - Universidad Autónoma de Occidente
dc.rights.coar.fl_str_mv http://purl.org/coar/access_right/c_abf2
dc.rights.uri.eng.fl_str_mv https://creativecommons.org/licenses/by-nc-nd/4.0/
dc.rights.accessrights.eng.fl_str_mv info:eu-repo/semantics/openAccess
dc.rights.creativecommons.spa.fl_str_mv Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)
rights_invalid_str_mv Derechos Reservados - Universidad Autónoma de Occidente
https://creativecommons.org/licenses/by-nc-nd/4.0/
Atribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)
http://purl.org/coar/access_right/c_abf2
eu_rights_str_mv openAccess
dc.format.eng.fl_str_mv application/pdf
dc.format.extent.spa.fl_str_mv 17 páginas
dc.coverage.spatial.none.fl_str_mv Universidad Autónoma de Occidente. Calle 25 115-85. Km 2 vía Cali-Jamundí
dc.publisher.eng.fl_str_mv MDPI
institution Universidad Autónoma de Occidente
bitstream.url.fl_str_mv https://red.uao.edu.co/bitstreams/51c246cb-98f1-4aae-b487-0103be26f069/download
https://red.uao.edu.co/bitstreams/1e747242-a5c8-4864-b7f6-6c46db33280e/download
https://red.uao.edu.co/bitstreams/e590ac5a-e492-43b0-a19e-f7f217c52146/download
https://red.uao.edu.co/bitstreams/c7290b87-986d-4fff-91c7-14584ead96aa/download
https://red.uao.edu.co/bitstreams/ce032228-0174-431f-8084-7e608fc23f32/download
bitstream.checksum.fl_str_mv 4460e5956bc1d1639be9ae6146a50347
20b5ba22b1117f71589c7318baa2c560
8c9afde60ce9fdb09acf8b733923451e
d242a34f44246ac4b818a4baf9d9f0bd
d1141b6cc6e2ea3887f25c2171c624f9
bitstream.checksumAlgorithm.fl_str_mv MD5
MD5
MD5
MD5
MD5
repository.name.fl_str_mv Repositorio Digital Universidad Autonoma de Occidente
repository.mail.fl_str_mv repositorio@uao.edu.co
_version_ 1828229872321822720
spelling Laín Beatove, Santiagovirtual::2539-1Lopez Mejia, Omar Dcb36c6c227058b2362ba55514ecb7c77Quiñones, Jhon J.773d37b110399f9fa5ed871dfda053f0Universidad Autónoma de Occidente. Calle 25 115-85. Km 2 vía Cali-Jamundí2019-11-01T20:57:47Z2019-11-01T20:57:47Z2018-09-061996-1073 (en línea)http://hdl.handle.net/10614/11390https://doi.org/10.1016/j.powtec.2018.03.026Nowadays, the global energy crisis has encouraged the use of alternative sources like the energy available in the water currents of seas and rivers. The vertical axis water turbine (VAWT) is an interesting option to harness this energy due to its advantages of facile installation, maintenance and operation. However, it is known that its efficiency is lower than that of other types of turbines due to the unsteady effects present in its flow physics. This work aims to analyse through Computational Fluid Dynamics (CFD) the turbulent flow dynamics around a small scale VAWT confined in a hydrodynamic tunnel. The simulations were developed using the Unsteady Reynolds Averaged Navier Stokes (URANS), Detached Eddy Simulation (DES) and Delayed Detached Eddy Simulation (DDES) turbulence models, all of them based on k-ω Shear Stress Transport (SST). The results and analysis of the simulations are presented, illustrating the influence of the tip speed ratio. The numerical results of the URANS model show a similar behaviour with respect to the experimental power curve of the turbine using a lower number of elements than those used in the DES and DDES models. Finally, with the help of both the Q-criterion and field contours it is observed that the refinements made in the mesh adaptation process for the DES and DDES models improve the identification of the scales of the vorticity structures and the flow phenomena present on the near and far wake of the turbineapplication/pdf17 páginasengMDPIDerechos Reservados - Universidad Autónoma de Occidentehttps://creativecommons.org/licenses/by-nc-nd/4.0/info:eu-repo/semantics/openAccessAtribución-NoComercial-SinDerivadas 4.0 Internacional (CC BY-NC-ND 4.0)http://purl.org/coar/access_right/c_abf2RANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbineArtículo de revistahttp://purl.org/coar/resource_type/c_6501http://purl.org/coar/resource_type/c_2df8fbb1Textinfo:eu-repo/semantics/articlehttp://purl.org/redcol/resource_type/ARTREFinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/version/c_970fb48d4fbd8a85Hydraulic turbinesTurbinas hidráulicasAerodynamicsAerodinámicaDarrieus turbineDelayed Detached Eddy SimulationDetached Eddy SimulationVertical axis water turbineComputational Fluid DynamicsHybrid RANS-LES models234811Mejia, O., Quiñones, J., & Laín, S. (2018). RANS and Hybrid RANS-LES Simulations of an H-Type Darrieus Vertical Axis Water Turbine. Energies, 11(9), 2348Energies1. Hall, T.J. Numerical Simulation of a Cross Flow Marine Hydrokinetic Turbine. Master’s Thesis, University of Washigton, Seattle,WA, USA, 2012.2. Antheaume, S.; Maitre, T.; Achard, J. Hydraulic darrieus turbines efficiency for free fluid flow conditions versus power farms conditions. Renew. Energies 2008, 33, 2186–2198. [CrossRef]3. Dai, Y.M.; Lam,W. Numerical Study of Straight-bladed Darrieus-type Tidal Turbine. ICE Energy 2009, 162, 67–76. [CrossRef]4. Lain, S.; Osorio, C. Simulation and Evaluation of a Straight-bladed Darrieus-type Cross Flow Marine Turbine. J. Sci. Ind. Res. (JSIR) 2010, 69, 906–912.5. Nabavi, Y. Numerical Study of the Ducted Shape Effect on the Performance of a Ducted Vertical Axis Tidal Turbine. Master’s Thesis, The University of British Columbia, Vancouver, BC, Canada, 2008.6. Rawlings, G.W. Parametric Characterization of an Experimental Vertical Axis Hydro Turbine. Master’s Thesis, The University of British Columbia, Vancouver, BC, Canada, 2008.7. Ferreira, C.J.; Bijl, H.; van Bussel, G.; van Kuik, G. Simulating Dynamic Stall in a 2D VAWT: Modeling Strategy, Verification and Validation with Particle Image Velocimetry Data. J. Phys. Conf. Ser. 2007, 75, 012023. [CrossRef]8. Lei, H.; Zhou, D.; Bao, Y.; Li, Y.; Han, Z. Three-dimensional Improved Delayed Detached Eddy Simulation of a two-bladed vertical axis wind turbine. Energy Convers. Manag. 2017, 133, 235–248. [CrossRef]9. Maître, T.; Amet, E.; Pellone, C. Modeling of the Flow in a DarrieusWater Turbine: Wall Grid Refinement Analysis and Comparison with Experiments. Renew. Energy 2013, 51, 497–512. [CrossRef]10. Marsh, P.; Ranmuthugala, D.; Penesis, I.; Thomas, G. Three Dimensional Numerical Simulations of a Straight-Bladed Vertical Axis Tidal Turbine. In Proceedings of the 18th Australasian Fluid Mechanics Conference, Launceston, Australia, 3–7 December 2012.11. Pellone, C.; Maître, T.; Amet, E. 3D RANS Modeling of a Cross Flow Water Turbine. In Proceedings of the SimHydro: New Trends in Simulation Hydroinformatics and 3D modeling, Nice, France, 12–14 September 2012.12. Amet, E. Simulation Numerique d’une Hydrolienne à Axe Vertical de Type Darrieus. Ph.D. Thesis, Institut Polytechnique Grenoble, Grenoble, France, 2009.13. Eca, L.; Hoekstra, M. A Verification Exercise for Two 2-D Steady Incompressible Turbulent Flows. In Proceedings of the ECCOMAS European Congress on Computational Methods in Applied Sciences and Engineering, Jyväskylä, Finland, 24–28 July 2004.14. Spalart, P.R.; Jou,W.-H.; Strelets,M.; Allmaras, S. Comments on the Feasibility of LES forWings, and on a Hybrid RANS/LES Approach. In Proceedings of the Advances in DNS/LES, Ruston, LA, USA, 4–8 August 1997.15. Shur, M.; Spalart, P.R.; Strelets, M.; Travin, A. Detached-eddy simulation of an airfoil at high angle of attack. In Proceedings of the Engineering TurbulenceModelling and Experiments-4, Corsica, France, 24–26May 1999.16. Spalart, P.R. Young-Person’s Guide to Detached-Eddy Simulation Grids; NASA/CR-2001-211032; NASA Langley Research Center: Hampton, VA, USA, 2001.17. Bussiere, M. The Experimental Investigation of Vortex Wakes from Oscillating Airfoils. Master’s Thesis, University of Alberta, Edmonton, AB, Canada, 2012.18. Gorle, J.M.; Chatellier, L.; Pons, F.; Ba, M. Flow and Performance analysis of H-Darrieus hydro turbine in a confined flow: A computational and experimental study. J. Fluids Struct. 2016, 66, 382–402. [CrossRef]19. Marsh, P.; Ranmuthugala, D.; Penesis, I.; Thomas, G. Three-dimensional Numerical Simulations of a Straight-Bladed Vertical Axis Tidal Turbine Investigating Power Output, Torque Ripple and Mounting Forces. Renew. Energy 2015, 83, 67–77. [CrossRef]Publication082b0926-3385-4188-9c6a-bbbed7484a95virtual::2539-1082b0926-3385-4188-9c6a-bbbed7484a95virtual::2539-1https://scholar.google.com/citations?user=g-iBdUkAAAAJ&hl=esvirtual::2539-10000-0002-0269-2608virtual::2539-1https://scienti.minciencias.gov.co/cvlac/visualizador/generarCurriculoCv.do?cod_rh=0000262129virtual::2539-1CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8805https://red.uao.edu.co/bitstreams/51c246cb-98f1-4aae-b487-0103be26f069/download4460e5956bc1d1639be9ae6146a50347MD52LICENSElicense.txtlicense.txttext/plain; charset=utf-81665https://red.uao.edu.co/bitstreams/1e747242-a5c8-4864-b7f6-6c46db33280e/download20b5ba22b1117f71589c7318baa2c560MD53ORIGINALRANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine.pdfRANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine.pdfTexto archivo completo del artículo de revista, PDFapplication/pdf1793937https://red.uao.edu.co/bitstreams/e590ac5a-e492-43b0-a19e-f7f217c52146/download8c9afde60ce9fdb09acf8b733923451eMD54TEXTRANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine.pdf.txtRANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine.pdf.txtExtracted texttext/plain59935https://red.uao.edu.co/bitstreams/c7290b87-986d-4fff-91c7-14584ead96aa/downloadd242a34f44246ac4b818a4baf9d9f0bdMD55THUMBNAILRANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine.pdf.jpgRANS and hybrid RANS-LES simulations of an H-Type darrieus vertical axis water turbine.pdf.jpgGenerated Thumbnailimage/jpeg15225https://red.uao.edu.co/bitstreams/ce032228-0174-431f-8084-7e608fc23f32/downloadd1141b6cc6e2ea3887f25c2171c624f9MD5610614/11390oai:red.uao.edu.co:10614/113902024-03-06 16:06:04.454https://creativecommons.org/licenses/by-nc-nd/4.0/Derechos Reservados - Universidad Autónoma de Occidenteopen.accesshttps://red.uao.edu.coRepositorio Digital Universidad Autonoma de Occidenterepositorio@uao.edu.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