| Titre : | Effect of impeller speed perturbation in a Rushton impeller stirred tank (2012) |
| Auteurs : | Somnath Roy, Auteur ; Sumanta Acharya, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Transactions of the ASME . Journal of fluids engineering (Vol. 134 N° 6, Juin 2012) |
| Article en page(s) : | 15 p. |
| Note générale : | fluids engineering |
| Langues : | Anglais |
| Index. décimale : | 620.1 (Essais des matériaux. Défauts des matériaux. Protection des matériaux) |
| Tags : | stirred tank ; perturbation ; impeller-jet ; turbulence ; trailing edge vortex |
| Résumé : | Flow inside an unbaffled Rushton-impeller stirred tank reactor (STR) is perturbed using a time dependent impeller rotational speed. Large eddy simulation (LES) revealed that the perturbation increased the width of impeller jet compared to the constant rotational speed cases. The turbulent fluctuations were also observed to be enhanced in the perturbed flow and showed higher values of production and convection of turbulent kinetic energy. Changes in the mean flow-field during the perturbation cycle are investigated. The trailing edge vortices were observed to propagate farther both in the radial and azimuthal direction in the perturbed case. Production of turbulent kinetic energy is observed to be related to the breakup of the impeller jet in the perturbed case. Dissipation of turbulent kinetic energy is augmented due to the perturbation ensuring a better mixing at the molecular scale. |
| DEWEY : | 620.1 |
| ISSN : | 0098-2202 |
| En ligne : | http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JFEGA4000134000006061104000001&idtype=cvips&gifs=Yes&ref=no |
