NATURAL CONVECTION IN A PARTIALLY HEATED PARALLELOGRAMMICAL CAVITY WITH V-SHAPED BAFFLE AND FILLED WITH VARIOUS NANOFLUIDS

The numerical analysis of a V-shaped baffle effect on the natural convection inside a parallelogrammical cavity filled with two different water-based nanofluids (Al2O3 and Cu) were studied in this work. The enclosure walls were maintained at a constant hot and cold temperatures on the left and right walls sequentially. The horizontal walls were isolated, while the baffles located on the right wall and sharing the same cold temperature with it. The finite element method was used to derive and solve the governing equations. The flow and thermal fields computed for different arrangements of: the number of baffles inside the cavity which were ranged as (1, 2, 3), length and position ranged as (0.25L <= l(b) <= 0.75L) and (0.25L <= h(b) <= 0.75L), respectively. These arrangements were discussed for the Rayleigh number range of (10(3), 10(5) and 10(6)). The effect of the solid volume fraction of the nanofluid also taken into account, which was ranged as (0.01 <= phi <= 0.06). As most important result, this study concluded that the best baffle length was (0.75L) and positioned at the middle height of the cavity while the two baffles is the optimum choice respecting to heat transfer enhancement. On the other hand, the average Nusselt number augmented with the Rayleigh number and the nanoparticles solid volume fraction increase for both (Al2O3) and (Cu), except that the enhancement of (Al2O3) nanoparticles was lower than that of (Cu) nanoparticles. Also, it is approved that the V-shaped baffle enhances the heat transfer as the rate gotten by a classical rectangular baffle although it has half its size.