in this paper, the problem of turbulent forced convection flow of water- alumina nanofluid in a uniformly heated pipe has been thoroughly investigated. in numerical study, single and two-phase models have been used. in single-phase modeling of nanofluid, thermal and flow properties of nanofluid have been considered to be dependent on temperature and volume fraction. effects of volume fraction a...

We review the numerical modelling of the nonlinear pulsations of classical variable stars with hydrocodes that include the effects of turbulent convection. Despite their simplicity these turbulent convective recipes appear to remove many of the difficulties that radiative codes faced. In particular, the numerical modelling of double mode pulsations has become possible.

A systematic study of turbulent Rayleigh-Bénard convection is carried out in two horizontal cylindrical cells of different lengths filled with water. Global heat transport and local temperature and velocity measurements are made over varying Rayleigh numbers Ra. The scaling behavior of the measured Nusselt number Nu(Ra) and the Reynolds number Re(Ra) associated with the large-scale circulation ...

Abstract To prevent buoyancy effects from increasing the overall heat transfer coefficient due to low flux, smooth vertical circular tubes require forced convection conjectures. Previous research has focused on mixed in turbulent regions and limited studies convective transfer. This study aims investigate predictable coefficients of performance under specific conditions convection, considering ...

in this paper, convection heat transfer of al2o3-water nanofluid turbulent flow through internally ribbed tubes with different rib shapes (rectangular, trapezoidal and semi-circular) is numerically investigated. for each rib shape, the optimum geometric ratio and volume fraction were calculated using entropy generation minimization technique. the governing equations in steady state and axisymme...

A one-dimensional turbulent convection model in the form of a time-dependent diffusion equation for the turbulent energy is incorporated into our numerical pulsation code. The effect of turbulent convection on the structural rearrangement of the static equilibrium star is taken into account, and the linear eigenvalues (periods and growth-rates) for the complete turbulent convective nonadiabatic...

We analyze stellar convection with the aid of 3D hydrodynamic simulations, introducing the turbulent cascade into our theoretical analysis. We devise closures of the Reynolds-decomposed mean field equations by simple physical modeling of the simulations (we relate temperature and density fluctuations via coefficients); the procedure (CABS, Convection Algorithm Based on Simulations) is terrestri...

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Subglacial lakes are isolated, cold-temperature and high-pressure water environments hidden under ice sheets, which might host extreme microorganisms. Here, we use two-dimensional direct numerical simulations in order to investigate the characteristic temperature fluctuations velocities freshwater subglacial as functions of overburden pressure, $p_i$, depth, $h$, geothermal flux, $F$. Geotherma...