[article]
Titre : |
Prediction of velocity profiles and Reynolds stress distributions in turbulent open-channel flows with adverse pressure gradient |
Titre original : |
Prévision des profils de vitesse et des distributions de contraintes de Reynolds dans les écoulements turbulents en canal avec un gradient contrainte de pression |
Type de document : |
texte imprimé |
Auteurs : |
Kouki Onitsuka, Auteur ; Juichiro Akiyama, Auteur ; Sadakatsu Matsuoka, Auteur |
Article en page(s) : |
pp. 58-65 |
Note générale : |
Hydraulique
Résumé en Français |
Langues : |
Anglais (eng) |
Mots-clés : |
Adverse pressure gradient Open-channel flow Prediction Reynolds stress |
Index. décimale : |
627 Ingénierie des cours d'eau naturels, des ports, des rades et des cotes. Installations de navigation, de dragage, de récupération et de sauvetage. Barrages et centrales électriques hydrauliques |
Résumé : |
Turbulence measurements in open-channel flows with adverse pressure gradient were conducted with an X-type hot-film anemometer. The velocity profiles in whole depth are described well by the log-wake law which involves a wake strength parameter Π. The wake strength parameter Π is controlled only by the pressure gradient parameter β in the equilibrium region, i.e., normalized velocity profiles are similar at all streamwise distances. A new relationship formula between the wake strength parameter Π and the pressure gradient parameter β is suggested on the basis of experimental data. The equation of motion and continuity equation are transformed to predict the velocity profiles and also the Reynolds stress distributions under the conditions that the flow is in equilibrium and the coefficient of velocity is constant in the streamwise direction. The wake strength parameter Π can be predicted with high accuracy from the obtained equations. The predicted Reynolds stress distributions correspond to the experimental data when the pressure gradient parameter β is low. On the other hand, the predicted ones do not correspond to the experimental data when the pressure gradient parameter β is high.
|
DEWEY : |
627 |
ISSN : |
0022-1686 |
En ligne : |
http://www.journalhydraulicresearch.com |
in Journal of hydraulic research > Vol. 47 N°1 (2009) . - pp. 58-65
[article] Prediction of velocity profiles and Reynolds stress distributions in turbulent open-channel flows with adverse pressure gradient = Prévision des profils de vitesse et des distributions de contraintes de Reynolds dans les écoulements turbulents en canal avec un gradient contrainte de pression [texte imprimé] / Kouki Onitsuka, Auteur ; Juichiro Akiyama, Auteur ; Sadakatsu Matsuoka, Auteur . - pp. 58-65. Hydraulique
Résumé en Français Langues : Anglais ( eng) in Journal of hydraulic research > Vol. 47 N°1 (2009) . - pp. 58-65
Mots-clés : |
Adverse pressure gradient Open-channel flow Prediction Reynolds stress |
Index. décimale : |
627 Ingénierie des cours d'eau naturels, des ports, des rades et des cotes. Installations de navigation, de dragage, de récupération et de sauvetage. Barrages et centrales électriques hydrauliques |
Résumé : |
Turbulence measurements in open-channel flows with adverse pressure gradient were conducted with an X-type hot-film anemometer. The velocity profiles in whole depth are described well by the log-wake law which involves a wake strength parameter Π. The wake strength parameter Π is controlled only by the pressure gradient parameter β in the equilibrium region, i.e., normalized velocity profiles are similar at all streamwise distances. A new relationship formula between the wake strength parameter Π and the pressure gradient parameter β is suggested on the basis of experimental data. The equation of motion and continuity equation are transformed to predict the velocity profiles and also the Reynolds stress distributions under the conditions that the flow is in equilibrium and the coefficient of velocity is constant in the streamwise direction. The wake strength parameter Π can be predicted with high accuracy from the obtained equations. The predicted Reynolds stress distributions correspond to the experimental data when the pressure gradient parameter β is low. On the other hand, the predicted ones do not correspond to the experimental data when the pressure gradient parameter β is high.
|
DEWEY : |
627 |
ISSN : |
0022-1686 |
En ligne : |
http://www.journalhydraulicresearch.com |
|