Temporal development of NACA airfoil wake affected by an upstream wake
Résumé
The study aims to uncover the consequence of the wake behind an obstacle by passing another object placed downstream. This issue pertains to wind turbine parks. A simple example is the interaction of a wake behind a cylinder and a blade placed downstream. The wake comprises coherent motions (CM) and random motion (RM). Coherent structures, reminiscent of the Von Kàrmàn street, are created by the obstacle and interact with random motion (RM), thus inducing locally enhanced turbulent cascade and impacted by any possible obstacle in the wake. 2C-2D in-plane velocity fields (190k images) are measured behind the obstacles (Cylinder-Blade) by high-speed Particle Image Velocimetry (H-PIV) to visualize the temporal development. Then, the lock phases numerical method is developed for further statistical studies. The measurement plane is at the center of the test section, with three different local Reynolds numbers based on the cylinder diameter, i.e., Re = 2000, 4000, and 8000.
Domaines
Sciences de l'ingénieur [physics]
Origine : Fichiers éditeurs autorisés sur une archive ouverte