| タイトル | First results of a study on turbulent boundary layers in oscillating flow with a mean adverse pressure gradient |
| 本文（外部サイト） | http://hdl.handle.net/2060/19800009140 |
| 著者（英） | Houdeville, R.; Cousteix, J. |
| 著者所属（英） | NASA Headquarters |
| 発行日 | 1979-11-01 |
| 言語 | eng |
| 内容記述 | The development of a turbulent unsteady boundary layer with a mean pressure gradient strong enough to induce separation, in order to complete the extend results obtained for the flat plate configuration is presented. The longitudinal component of the velocity is measured using constant temperature hot wire anemometer. The region where negative velocities exist is investigated with a laser Doppler velocimeter system with BRAGG cells. The boundary layer responds by forced pulsation to the perturbation of potential flow. The unsteady effects observed are very important. The average location of the zero skin friction point moves periodically at the perturbation frequency. Average velocity profiles from different instants in the cycle are compared. The existence of a logarithmic region enables a simple calculation of the maximum phase shift of the velocity in the boundary layer. An attempt of calculation by an integral method of boundary layer development is presented, up to the point where reverse flow starts appearing. |
| NASA分類 | FLUID MECHANICS AND HEAT TRANSFER |
| レポートNO | 80N17400
NASA-TM-75799 |
| 権利 | No Copyright |
