Documents disponibles écrits par cet auteur

Modification of axial fan flow by trailing edge self-induced blowing / Matjaž Eberlinc in Transactions of the ASME . Journal of fluids engineering, Vol. 131 N° 11 (Novembre 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of fluids engineering > Vol. 131 N° 11 (Novembre 2009) . - 07 p. Titre : Modification of axial fan flow by trailing edge self-induced blowing Type de document : texte imprimé Auteurs : Matjaž Eberlinc, Auteur ; Sirok, Brane, Auteur ; Matevž Dular, Auteur Année de publication : 2010 Article en page(s) : 07 p. Note générale : fluids engineering Langues : Anglais (eng) Mots-clés : flow  (dynamics);  measurement;  wire;  internal  flow;  blades;  probes;  pressure Résumé : Axial fans often show adverse flow conditions at the fan hub and at the tip of the blade. The modification of conventional axial fan blade is presented. Hollow blade was manufactured from the hub to the tip. It enables the formation of self-induced internal flow through internal passages. The internal flow enters the passage of the hollow blade through the opening near the fan hub and exits through the trailing edge slots at the tip of the hollow blade. The study of the influence of internal flow on the flow field of axial fan and modifications of axial fan aerodynamic characteristics is presented. The characteristics of the axial fan with the internal flow were compared to characteristics of a geometrically equivalent fan without internal flow. The results show integral measurements of performance testing using standardized test rig and the measurements of local characteristics. The measurements of local characteristics were performed with a hot-wire anemometry and a five-hole probe. Reduction in adverse flow conditions near the trailing edge at the tip of the hollow blade, boundary-layer reduction in the hollow blade suction side, and reduction in flow separation were attained. The introduction of the self-induced blowing led to the preservation of external flow direction defined by the blade geometry, which enabled maximal local energy conversion. The integral characteristic reached a higher degree of efficiency. En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...] [article] Modification of axial fan flow by trailing edge self-induced blowing [texte imprimé] / Matjaž Eberlinc, Auteur ; Sirok, Brane, Auteur ; Matevž Dular, Auteur . - 2010 . - 07 p. fluids engineering Langues : Anglais (eng) in Transactions of the ASME . Journal of fluids engineering > Vol. 131 N° 11 (Novembre 2009) . - 07 p. Mots-clés : flow  (dynamics);  measurement;  wire;  internal  flow;  blades;  probes;  pressure Résumé : Axial fans often show adverse flow conditions at the fan hub and at the tip of the blade. The modification of conventional axial fan blade is presented. Hollow blade was manufactured from the hub to the tip. It enables the formation of self-induced internal flow through internal passages. The internal flow enters the passage of the hollow blade through the opening near the fan hub and exits through the trailing edge slots at the tip of the hollow blade. The study of the influence of internal flow on the flow field of axial fan and modifications of axial fan aerodynamic characteristics is presented. The characteristics of the axial fan with the internal flow were compared to characteristics of a geometrically equivalent fan without internal flow. The results show integral measurements of performance testing using standardized test rig and the measurements of local characteristics. The measurements of local characteristics were performed with a hot-wire anemometry and a five-hole probe. Reduction in adverse flow conditions near the trailing edge at the tip of the hollow blade, boundary-layer reduction in the hollow blade suction side, and reduction in flow separation were attained. The introduction of the self-induced blowing led to the preservation of external flow direction defined by the blade geometry, which enabled maximal local energy conversion. The integral characteristic reached a higher degree of efficiency. En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...]

Unsteady cavitation at the tongue of the volute of a centrifugal pump / Rudolf Bachert in Transactions of the ASME . Journal of fluids engineering, Vol. 132 N° 6 (Juin 2010) 

Public ISBD [article]  in Transactions of the ASME . Journal of fluids engineering > Vol. 132 N° 6 (Juin 2010) . - 06 p. Titre : Unsteady cavitation at the tongue of the volute of a centrifugal pump Type de document : texte imprimé Auteurs : Rudolf Bachert, Auteur ; Bernd Stoffel, Auteur ; Matevž Dular, Auteur Année de publication : 2010 Article en page(s) : 06 p. Note générale : fluids engineering Langues : Anglais (eng) Mots-clés : flow  (dynamics);  impellers;  cavitation;  pumps;  blades;  centrifugal  pumps Résumé : The paper deals with unsteady effects of cavitation at the tongue of the volute of a centrifugal pump. For the investigations parts of the volute casing, including the tongue and the hub of the impeller, were made of acrylic glass. Experiments were carried out at a flow rate above optimal value (slight overload) and at 3% head drop conditions. In this operating point there was no cavitation present in the impeller of the pump, hence, the whole 3% head drop resulted from cavitation on the tongue of the volute. By use of particle image velocimetry combined with special fluorescent particles it was possible to obtain information about the velocity field outside and inside the cavitating zone. An additional camera provided information about the location and extent of cavitation. The results imply that cloud cavitation similar to the one seen on single hydrofoils appears on the tongue. Periodical evolution of cavitation structures, from incipient to developed, with cavitation cloud shedding, is seen during each passing of a blade. The Results imply that greater consideration should be given to the possibility of cavitation appearance on the tongue of the volute as it is possible that this cavitation location alone causes the 3% head drop. Moreover, the appearance of unsteady cavitation in a higher-pressure region, such as the volute of the pump, can cause severe erosion to the solid surfaces. DEWEY : 620.1 ISSN : 0098-2202 En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...] [article] Unsteady cavitation at the tongue of the volute of a centrifugal pump [texte imprimé] / Rudolf Bachert, Auteur ; Bernd Stoffel, Auteur ; Matevž Dular, Auteur . - 2010 . - 06 p. fluids engineering Langues : Anglais (eng) in Transactions of the ASME . Journal of fluids engineering > Vol. 132 N° 6 (Juin 2010) . - 06 p. Mots-clés : flow  (dynamics);  impellers;  cavitation;  pumps;  blades;  centrifugal  pumps Résumé : The paper deals with unsteady effects of cavitation at the tongue of the volute of a centrifugal pump. For the investigations parts of the volute casing, including the tongue and the hub of the impeller, were made of acrylic glass. Experiments were carried out at a flow rate above optimal value (slight overload) and at 3% head drop conditions. In this operating point there was no cavitation present in the impeller of the pump, hence, the whole 3% head drop resulted from cavitation on the tongue of the volute. By use of particle image velocimetry combined with special fluorescent particles it was possible to obtain information about the velocity field outside and inside the cavitating zone. An additional camera provided information about the location and extent of cavitation. The results imply that cloud cavitation similar to the one seen on single hydrofoils appears on the tongue. Periodical evolution of cavitation structures, from incipient to developed, with cavitation cloud shedding, is seen during each passing of a blade. The Results imply that greater consideration should be given to the possibility of cavitation appearance on the tongue of the volute as it is possible that this cavitation location alone causes the 3% head drop. Moreover, the appearance of unsteady cavitation in a higher-pressure region, such as the volute of the pump, can cause severe erosion to the solid surfaces. DEWEY : 620.1 ISSN : 0098-2202 En ligne : http://fluidsengineering.asmedigitalcollection.asme.org/issue.aspx?journalid=122 [...]