The effects of strong density variations on the dynamics of instabilities which develop in axisymmetric jets of pure air or pure helium are studied in the near field. By using LDV measurements associated with fast visualization techniques, space–time diagrams are built in order to show the evolution of the structures along the jets according to their Reynolds number and their density. In particular, the global character of the helium jet instabilities is highlighted.
On étudie l'influence de fortes variations de masse volumique sur la dynamique des instabilités qui se développent dans des jets axisymétriques d'air pur ou d'hélium pur en proche sortie de buse. Associées à des mesures par VLD, les techniques de visualisations rapides sont utilisées pour construire des diagrammes spatio-temporels qui montrent l'évolution des structures le long des jets en fonction du nombre de Reynolds et de leur masse volumique. On met en particulier en évidence le caractère global de l'instabilité du jet d'hélium.
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Keywords: Fluid mechanics, Jet, Instability, Variable density
Sami Boujemaa 1; Muriel Amielh 2; Marie Pierre Chauve 2
@article{CRMECA_2004__332_11_933_0, author = {Sami Boujemaa and Muriel Amielh and Marie Pierre Chauve}, title = {Analyse spatio-temporelle de jets axisym\'etriques d'air et d'h\'elium}, journal = {Comptes Rendus. M\'ecanique}, pages = {933--939}, publisher = {Elsevier}, volume = {332}, number = {11}, year = {2004}, doi = {10.1016/j.crme.2004.06.009}, language = {fr}, }
TY - JOUR AU - Sami Boujemaa AU - Muriel Amielh AU - Marie Pierre Chauve TI - Analyse spatio-temporelle de jets axisymétriques d'air et d'hélium JO - Comptes Rendus. Mécanique PY - 2004 SP - 933 EP - 939 VL - 332 IS - 11 PB - Elsevier DO - 10.1016/j.crme.2004.06.009 LA - fr ID - CRMECA_2004__332_11_933_0 ER -
Sami Boujemaa; Muriel Amielh; Marie Pierre Chauve. Analyse spatio-temporelle de jets axisymétriques d'air et d'hélium. Comptes Rendus. Mécanique, Volume 332 (2004) no. 11, pp. 933-939. doi : 10.1016/j.crme.2004.06.009. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2004.06.009/
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