Results are presented from a series of analytical and numerical studies of buoyantly driven flows along heated vertical surfaces immersed in stably stratified fluids. Flows of the studied type are broadly represented in engineering and geophysical applications. First, the classical problem of one-dimensional natural convection flow along a heated wall is revisited for the case of a stably strat...

In this paper we apply the finite difference method on adaptive sparse grids [9] to the simulation of turbulent flows. This method combines the flexibility and efficiency of finite difference schemes with the advantages of an adaptive approximation by tensor product multiscale bases. We shortly discuss the method. Then, we present numerical results for a simple linear convection problem for a v...

The acoustic power injected by turbulent convection into solar-like oscillations depends on the details of the turbulent spectrum. A theoretical formulation for the oscillation power is developed which generalizes previous ones. The formulation is first calibrated on a solar model in such a way as to reproduce the solar seismic data. This allows to investigate different assumptions about the st...

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Related Articles Lagrangian evolution of the invariants of the velocity gradient tensor in a turbulent boundary layer Phys. Fluids 24, 105104 (2012) Effects of moderate Reynolds numbers on subsonic round jets with highly disturbed nozzle-exit boundary layers Phys. Fluids 24, 105107 (2012) Particle transport in a turbulent boundary layer: Non-local closures for particle dispersion tensors accoun...

Related Articles Lagrangian evolution of the invariants of the velocity gradient tensor in a turbulent boundary layer Phys. Fluids 24, 105104 (2012) Effects of moderate Reynolds numbers on subsonic round jets with highly disturbed nozzle-exit boundary layers Phys. Fluids 24, 105107 (2012) Particle transport in a turbulent boundary layer: Non-local closures for particle dispersion tensors accoun...

this paper presents a three-dimensional numerical investigation carried out in turbulent forced convection in a tube with helical ribs. enhancement of heat transfer using helically corrugated tubes has beenstudied experimentally by many researchers but there exist a few published numerical analyses results. the paper also introduces the results of heat transfer and friction factor data for inco...

In the present work, a theoretical model based on the integral formalism approach for both laminar and turbulent external free convection is extended to Newtonian nanofluids. By using an empirical model for computing nanofluid viscosity, a close attention is focused first on the way the heat transfer is modified by increasing the volume fraction of nanoparticles and then to the transitional thr...

Stellar evolution models of stars of 1.45 to 3.0M have been calculated including the atomic di usion of metals and radiative accelerations for all species in the OPAL opacities. As the abundances change, the opacities and radiative accelerations are continuously recalculated during evolution. These models develop iron peak convection zones centered at a temperature of approximately 200 000K. If...

According to conventional view, sunspots form when coherent magnetic flux tubes intersect the surface. Such tubes would rise from the bottom of the convection zone as a result of an instability. In this study an alternative view is advanced where the field is produced throughout the entire convection zone and sunspots may form from local flux concentrations near the surface. In order to underst...