We demonstrate, via simulations of asymptotically reduced equations describing rotationally constrained Rayleigh-Bénard convection, that the efficiency of turbulent motion in the fluid bulk limits overall heat transport and determines the scaling of the nondimensional Nusselt number Nu with the Rayleigh number Ra, the Ekman number E, and the Prandtl number σ. For E << 1 inviscid scaling theory ...

High-resolution numerical simulations of statistically steady convection in a threedimensional porous medium are presented for Rayleigh numbers Ra 6 2 × 104. Measurements of the Nusselt number Nu in the range 1750 6 Ra 6 2× 104 are well fitted by a relationship of the form Nu= α3Ra+ β3, for α3= 9.6× 10−3 and β3= 4.6. This fit indicates that the classical linear scaling Nu∼ Ra is attained, and t...

Rayleigh-Bénard convection is numerically simulated in twoand three-dimensions using a recently developed two-component lattice Boltzmann equation (LBE) method. The density field of the second component, which evolves according to the advection-diffusion equation of a passive-scalar, is used to simulate the temperature field. A body force proportional to the temperature is applied, and the syst...