In this work we study numerically the three-dimensional turbulent natural
convection in a partially heated cubic cavity filled with water containing
metallic nanoparticles, metallic oxides and others based on carbon.The
objective is to study and compare the effect of the addition of
nanoparticles studied in water and also the effect of the position of the
heated partition on the heat exchange by turbulent natural convection in
this type of geometry, which can significantly improve the design of heat
exchange systems for better space optimization. For this we have treated
numerically for different volume fractions the turbulent natural convection
in the two cases where the cavity is heated respectively by a vertical and
horizontal strip in the middle of one of the vertical walls. To take into
account the effects of turbulence, we used the standard turbulence model ? -
?. The governing equations are discretized by the finite volume method using
the power law scheme which offers a good stability characteristic in this
type of flow. The results are presented in the form of isothermal lines and
current lines. The variation of the mean Nusselt number is calculated for
the two positions of the heated partition as a function of the volume
fraction of the nanoparticles studied in water for different Rayleigh
numbers.The results show that carbon-based nanoparticles intensify heat
exchange by convection better and that the position of the heated partition
significantly influences heat exchange by natural convection. In fact, an
improvement in the average Nusselt number of more than 20% is observed for
the case where the heated partition is horizontal.
Numerical study of the turbulent natural convection of nanofluids in a partially heated cubic cavity