Predicting transition ranges to fully turbulent viscous boundary layers in low Prandtl number convection flows
نویسندگان
چکیده
منابع مشابه
The Anisotropy of Low Prandtl Number Turbulent Convection
A model for homogeneous anisotropic incompressible turbulence is proposed. The model generalizes the GISS model of homogeneous isotropic turbulence; the generalization involves the solution of the GISS equations along a set of integration paths in wavenumber (k-) space. In order to make the problem tractable, these integration paths (“cascade lines”) must be chosen in such a way that the behavi...
متن کاملPrandtl number dependence of the viscous boundary layer and the Reynolds numbers in Rayleigh-Bénard convection.
We report results from high Prandtl number turbulent thermal convection experiments. The viscous boundary layer and the Reynolds number are measured in four different fluids over wide ranges of the Prandtl number Pr and the Rayleigh number Ra, all in a single convection cell of unity aspect ratio. We find that the normalized viscous layer thickness may be represented as delta(v)/L=0.65Pr(0.24)R...
متن کاملReynolds-number measurements for low-Prandtl-number turbulent convection of large-aspect-ratio samples
We present experimental results for the Reynolds number ReU based on the horizontal mean-flow velocity U and for ReV based on the root-mean-square horizontal fluctuation velocity V for turbulent Rayleigh–Bénard convection in a cylindrical sample of aspect ratio Γ = 10.9 over the Prandtl number range 0.18 6 Pr 6 0.88. The results were derived from space–time cross-correlation functions of shadow...
متن کاملTurbulent Rayleigh–Bénard convection for a Prandtl number of 0.67
For the Rayleigh-number range 10 Ra 10 we report measurements of the Nusselt number Nu and of properties of the large-scale circulation (LSC) for cylindrical samples of helium gas (Prandtl number Pr=0.674) that have aspect ratio Γ ≡D/L=0.50 (D and L are the diameter and the height respectively) and are heated from below. The results for Nu are consistent with recent direct numerical simulations...
متن کاملSpatial structure of the viscous boundary layer in turbulent convection
We present an experimental study of the spatial structure of the velocity field in the boundary layer region of a Rayleigh-Bénard convection cell, using water as the working fluid. Our results show that the mean flow, the shear rate, and the viscous boundary layer thickness all change significantly across the conducting horizontal surface of the cell. Moreover, the measurements reveal that the ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Review Fluids
سال: 2017
ISSN: 2469-990X
DOI: 10.1103/physrevfluids.2.123501