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Dissipation and cavitation characteristics of single-hole orifices / Malavasi, Stefano in Transactions of the ASME . Journal of fluids engineering, Vol. 133 N° 5 (Mai 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of fluids engineering > Vol. 133 N° 5 (Mai 2011) . - 08 p. Titre : Dissipation and cavitation characteristics of single-hole orifices Type de document : texte imprimé Auteurs : Malavasi, Stefano, Auteur ; Vittorio Messa, Gianandrea, Auteur Année de publication : 2011 Article en page(s) : 08 p. Note générale : Fluids engineering Langues : Anglais (eng) Mots-clés : Boundary  layer  turbulence  Cavitation  Computational  fluid  dynamics  Flow  simulation  Fractals  Pipe  flow Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The purpose of this work is to study the dependence of the pressure losses through sharp-edged orifices with respect to the most significant parameters and to find an efficient way to check whether cavitation is likely to occur. Computational fluid dynamics was used to simulate the flow through orifices with different geometrical characteristics for various incoming flow velocities. In particular, the diameter ratio was varied between 0.39 and 0.70, the relative thickness between 0.30 and 1.40, and the pipe Reynolds number between 3.85 × 104 and 1.54 × 105. The computed pressure drop coefficient in the region of self-similarity with respect to the pipe Reynolds number was first compared to that obtained from some literature models. Afterwards, the comparison with experimental data revealed that an extended pressure criterion is suitable to predict the presence of cavitating conditions. A dimensionless minimum pressure coefficient was then defined, and its dependence upon the above mentioned geometrical and flow parameters was investigated. Finally, a practical formula for the prediction of cavitation was provided. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JFEGA400013 [...] [article] Dissipation and cavitation characteristics of single-hole orifices [texte imprimé] / Malavasi, Stefano, Auteur ; Vittorio Messa, Gianandrea, Auteur . - 2011 . - 08 p. Fluids engineering Langues : Anglais (eng) in Transactions of the ASME . Journal of fluids engineering > Vol. 133 N° 5 (Mai 2011) . - 08 p. Mots-clés : Boundary  layer  turbulence  Cavitation  Computational  fluid  dynamics  Flow  simulation  Fractals  Pipe  flow Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : The purpose of this work is to study the dependence of the pressure losses through sharp-edged orifices with respect to the most significant parameters and to find an efficient way to check whether cavitation is likely to occur. Computational fluid dynamics was used to simulate the flow through orifices with different geometrical characteristics for various incoming flow velocities. In particular, the diameter ratio was varied between 0.39 and 0.70, the relative thickness between 0.30 and 1.40, and the pipe Reynolds number between 3.85 × 104 and 1.54 × 105. The computed pressure drop coefficient in the region of self-similarity with respect to the pipe Reynolds number was first compared to that obtained from some literature models. Afterwards, the comparison with experimental data revealed that an extended pressure criterion is suitable to predict the presence of cavitating conditions. A dimensionless minimum pressure coefficient was then defined, and its dependence upon the above mentioned geometrical and flow parameters was investigated. Finally, a practical formula for the prediction of cavitation was provided. DEWEY : 620.1 ISSN : 0742-4795 En ligne : http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JFEGA400013 [...]