Boundary layers in turbulent Rayleigh-Bénard convection: The 3D velocity field

Abstract eng:
We present the fillly three-dimensional boundary layer flow field in turbulent Rayleigh-Bénard convection in air. The experiments have been performed in the large-scale convection facility ‘Barrel of Ilmenau’ and cover a parameter range in Rayleigh number between Ra = 108 and Ra = 1012. The aspect ratio was kept constant at F = 1 and the Prandtl number is Pr = 0.7. Using a tomographic Particle Image Velocimetry set-up the fillly three dimensional velocity field at the lower surface of the cooling plate has been measured. In our talk we will show first results of these measurements that are still being in progress. We will discuss as well statistical properties of the near-wall flow field, like profiles of all three components of the mean velocity and the fluctuations, the vorticity and the Reynolds stresses as the dynamics of the boundary layer like time series of the boundary layer thickness or the temporal evolution of the wall shear stress.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket