Abstract: This research presents the design and analysis of solar
air-conditioning systems particularly solar chimney which is a
passive strategy for natural ventilation, and demonstrates the
structures of these systems’ using Computational Fluid Dynamic
(CFD) and finally compares the results with several examples, which
have been studied experimentally and carried out previously. In order
to improve the performance of solar chimney system, highly efficient
sub-system components are considered for the design. The general
purpose of the research is to understand how efficiently solar
chimney systems generate cooling, and is to improve the efficient of
such systems for integration with existing and future domestic
buildings.
Abstract: This paper presents a numerical study on surface heat
transfer characteristics of laminar air flows in parallel-plate dimpled
channels. The two-dimensional numerical model is provided by
commercial code FLUENT and the results are obtained for channels
with symmetrically opposing hemi-cylindrical cavities onto both
walls for Reynolds number ranging from 1000 to 2500. The influence
of variations in relative depth of dimples (the ratio of cavity depth to
the cavity curvature diameter), the number of them and the thermophysical
properties of channel walls on heat transfer enhancement is
studied. The results are evident for existence of an optimum value for
the relative depth of dimples in which the largest wall heat flux and
average Nusselt number can be achieved. In addition, the results of
conjugation simulation indicate that the overall influence of the ratio
of wall thermal conductivity to the one of the fluid on heat transfer
rate is not much significant and can be ignored.