We present measurements of the normalized charge transport or Nusselt number Nu as a function of the aspect ratio Gamma for turbulent convection in an electrically driven film. In analogy with turbulent Rayleigh-Bénard convection, we develop the relevant theoretical framework in which we discuss the local power-law scaling of Nu with a dimensionless electrical forcing parameter R. For these exp...

We report experiments on turbulent Rayleigh-Bénard convection of air in a cylindrical large-scale facility with a diameter of 7 meters and Rayleigh numbers up to Ra approximately 10(12). The facility is used to explore the structure of the large-scale circulation for continuously varying aspect ratios between Gamma approximately 1 and Gamma approximately 10. Using autocorrelation functions deri...

A numerical investigation has been carried out for mixed convection flow in a rectangularventilated cavity with a heat conducting solid circular cylinder at the center. Forced convection flowconditions were imposed by providing an inlet at the bottom of the left wall and an outlet vent at the topto the other sidewall. In this paper, the effect of cavity aspect ratio as well as the mixed convect...

We report experimental measurements of heat transport in rotating Rayleigh-Bénard convection in a cylindrical convection cell with an aspect ratio of Γ=1/2. The fluid is helium gas with a Prandtl number Pr=0.7. The range of control parameters for Rayleigh numbers 4×10^{9}<Ra<4×10^{11} and for Ekman numbers 2×10^{-7}<Ek<3×10^{-5} (corresponding to Taylor numbers 4×10^{9}<Ta<1×10^{14} and convect...

Vertical convection (VC) under the action of vertical vibration in a square cavity has been investigated using direct numerical simulation. The simulations are conducted with Prandtl number Pr fixed at 4.38 and Rayleigh Ra ranging from [Formula: see text] to text]. To examine influence vibration, dimensionless frequency is varied range small amplitude First, for low frequency, trivial results o...

[1] It is often assumed that ventilation of the atmospheric boundary layer is weak in the absence of fronts, but is this always true? In this paper we investigate the processes responsible for ventilation of the atmospheric boundary layer during a nonfrontal day that occurred on 9 May 2005 using the UK Met Office Unified Model. Pollution sources are represented by the constant emission of a pas...

The Mixed Scale Diffusivity Model, originally developed in the case of the differentially heated cavity, is applied to compute turbulent Rayleigh-Bénard flow in an infinite fluid layer at Pr = 0.71 for a large range of Rayleigh numbers (6.3 × 10 – 2 × 10). The effect of this SGS modelling, which adjusts locally the SGS diffusivity to the thermal scales of the flow and results in variable PrSGS ...

Results from kinematic solar dynamo models employing α-effect and turbulent pumping from local convection calculations are presented. We estimate the magnitude of these effects to be around 2–3 m s, having scaled the local quantities with the convective velocity at the bottom of the convection zone from a solar mixing-length model. Rotation profile of the Sun as obtained from helioseismology is...