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Efficiency improvement of centrifugal reverse pumps / Shahram Derakhshan in Transactions of the ASME . Journal of fluids engineering, Vol. 131 N° 2 (Fevrier 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of fluids engineering > Vol. 131 N° 2 (Fevrier 2009) . - 09 p. Titre : Efficiency improvement of centrifugal reverse pumps Type de document : texte imprimé Auteurs : Shahram Derakhshan, Auteur ; Bijan Mohammadi, Auteur ; Ahmad Nourbakhsh, Auteur Année de publication : 2009 Article en page(s) : 09 p. Note générale : fluids engineering Langues : Anglais (eng) Mots-clés : reverse  pumps;  turbines;  Navier–Stokes  flow  solver Résumé : Pumps as turbines have been successfully applied in a wide range of small hydrosites in the world. Since the overall efficiency of these machines is lower than the overall efficiency of conventional turbines, their application in larger hydrosites is not economical. Therefore, the efficiency improvement of reverse pumps is essential. In this study, by focusing on a pump impeller, the shape of blades was redesigned to reach a higher efficiency in turbine mode using a gradient based optimization algorithm coupled by a 3D Navier–Stokes flow solver. Also, another modification was done by rounding the blades’ leading edges and hub/shroud interface in turbine mode. After each modification, a new impeller was manufactured and tested in the test rig. The efficiency was improved in all measured points by the optimal design of the blade and additional modification as the rounding of the blade’s profile in the impeller inlet and hub/shroud inlet edges in turbine mode. Experimental results confirmed the numerical efficiency improvement in all measured points. This study illustrated that the efficiency of the pump in reverse operation can be improved just by impeller modification. DEWEY : 620.1 ISSN : 0098-2202 En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...] [article] Efficiency improvement of centrifugal reverse pumps [texte imprimé] / Shahram Derakhshan, Auteur ; Bijan Mohammadi, Auteur ; Ahmad Nourbakhsh, Auteur . - 2009 . - 09 p. fluids engineering Langues : Anglais (eng) in Transactions of the ASME . Journal of fluids engineering > Vol. 131 N° 2 (Fevrier 2009) . - 09 p. Mots-clés : reverse  pumps;  turbines;  Navier–Stokes  flow  solver Résumé : Pumps as turbines have been successfully applied in a wide range of small hydrosites in the world. Since the overall efficiency of these machines is lower than the overall efficiency of conventional turbines, their application in larger hydrosites is not economical. Therefore, the efficiency improvement of reverse pumps is essential. In this study, by focusing on a pump impeller, the shape of blades was redesigned to reach a higher efficiency in turbine mode using a gradient based optimization algorithm coupled by a 3D Navier–Stokes flow solver. Also, another modification was done by rounding the blades’ leading edges and hub/shroud interface in turbine mode. After each modification, a new impeller was manufactured and tested in the test rig. The efficiency was improved in all measured points by the optimal design of the blade and additional modification as the rounding of the blade’s profile in the impeller inlet and hub/shroud inlet edges in turbine mode. Experimental results confirmed the numerical efficiency improvement in all measured points. This study illustrated that the efficiency of the pump in reverse operation can be improved just by impeller modification. DEWEY : 620.1 ISSN : 0098-2202 En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...]