Experimental and Numerical Analysis of a PCM-Supported ...

spherical packing while in contact with low humidity counter current air stream.
Partial evaporation and convective heat transfer cools the brine down, which leaves
the evaporation unit concentrated at a lower temperature. Part of the outlet warm
brine is blown down to keep the salinity concentration within a certain limit, while the
other part is re-circulated back and mixed with the seawater makeup, and hence the
cycle is repeated. The brine and seawater makeup is heated up through recovery of
latent heat of condensation in a heat exchanger downstream of the condenser. The
brine is then heated up further through a solar collector during the day time or
bypassed to the external thermal buffer to avoid heat losses through the collector
during the night time. The solar collector should be over designed to store the
excessive energy during day time in the external thermal buffer to be utilized for
night operation.
Figure 3.1: Schematic layout of the PCM-Supported HDH desalination unit
(AquaTube)
The humidified air is guided by forced convection into the air cooler (dehumidifier)
where the sub-cooled water is gently sprayed in tiny droplets at the top of the
condenser and trickles downward by gravity concurrently with the hot humidified air.
The liquid droplets eventually form a liquid film on the surface of the spherical
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