Mixed convection heat transfer in a 3-D ventilated cavity is studied numerically using finite volume method. The results are presented in terms of streamlines, temperature distribution, velocity fields, and average Nusselt number for different combinations of thermal and geometrical controlling parameters, namely, Reynolds number, Re = 100, Richardson number (0.

Free convective flow in a cubical cavity loaded with copper-water nanofluid was examined numerically by employing a non-homogeneous dynamic model, which is physically more realistic in representing nanofluids than homogenous ones. The cavity was introduced to a horizontal magnetic field from the left sidewall. Both the cavity’s vertical left and right sidewalls are preserved at an isothermal cold temperature (Tc). The cavity includes inside it four isothermal heating blocks in the middle of the top and bottom walls. The other cavity walls are assumed adiabatic. Simulations were performed for solid volume fraction ranging from (0 ≤ ϕ ≤ 0.06), Rayleigh number varied as (103 ≤ Ra ≤ 105), the Hartmann number varied as (0 ≤ Ha ≤ 60), and the diameter of nanoparticle varied as (10 nm ≤ dp ≤ 130 nm). It was found that at (dp = 10 nm), the average Nusselt number declines when Ha increases, whereas it increases as (Ra) and (ϕ) increase. Furthermore, the increasing impact of the magnetic field on the average Nusselt number is absent for (Ra = 103), and this can be seen for all values of (ϕ). However, when (dp) is considered variable, the average Nusselt number was directly proportional to (Ra) and (ϕ) and inversely proportional to (dp).

A numerical investigation has been carried out to analyze the mixed convection heat transfer in isothermal heating source within three-dimensional ventilated cavity with different inletoutlet locations by using finite volume method. The results are presented in terms of flow structures, temperature distribution, and average Nusselt number for various combinations of thermal controlling parameters, namely, Reynolds number (50 ≤ Re ≤ 100) and Richardson number (0 ≤ Ri ≤ 10). The obtained results show that the flow intensity and the heat transfer rate can be significantly improved by an optimal choice of the mentioned parameters for different inlet-outlet locations.

The present work consists of analysing heat exchange by natural convection. The intensification of these exchanges and the improvement of efficiency have become a major issue in the industrial world today. This paper is part of this framework, and is particularly concerned with problems related to the intensification of heat exchanges in electronic components. Our objective is to understand the effect of the nanofluid on the mechanism of natural laminar convection in a three-dimensional cavity. In this context, we have developed our own computational code and conducted a parametric study looking at thermomechanical and geometrical parameters. The fluid flow and heat transfer in the cavity are studied for different sets of the governing parameters, namely the Rayleigh number Ra = 10 3 ,10 4 ,10 5 and 10 6 , volume fraction Ф varying between Ф = 0% and 10% and nanofluid type. The obtained results show a positive effect of the volume fraction and the Rayleigh number on the heat transfer improvement. It should also be noted that the increase of the heating section size and Ra results in increased amount of heat removed by the same nanofluid. Similarly, increasing the volume fraction causes the intensification of the flow and an increase of the heat exchange.

The 3-D mixed convective heat transfer inside a ventilated cavity partially heated is studied numerically by using control volume method. The heating square portion similar to the integrated electronic devices is placed on the left vertical wall of the enclosure. The right vertical wall is maintained at ambient temperature and all other walls are adiabatic. The results are presented in terms of flow structures, temperature distribution, and global average Nusselt number for various combinations of thermal controlling parameters, namely, the Richardson number (0 ≤ Ri ≤ 10), the Reynolds number (10 ≤ Ri ≤ 200), the heating section dimension (0. ≤ ε ≤ 0.7), and the relative height of the openings B = h/L = 1/8. It is found that for the low Reynolds number the heat transfer process is carried out only by conduction. On the other hand, the highest thermal performance is achieved by reducing the heating section dimension.