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Time (min)
0
30
60
90 120 150 180 210 240 270
Liquid fraction
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Base case
Case-1 inner zone
Case-1 outer zone
Case-2 lower zone
Case-2 upper zone
Fig. 2 Variation of the liquid fraction on the effect of with (case-1 and case-2) and without partition
(base case)
PCM in upper and lower zones is found to be 152 min and 228 min, respectively.
The total melting time of PCM for case 2 is 10.94% lower than the base case. This
shows that the introduction of partition in the TES system reduces total melting time
of PCM and thus improves its performance. Further, it is observed that the annular
partition (case 1) leads to better performance compared to radial partition (case 2) in
case of equal distribution of storage material in each zone.
Liquid fraction contour showing melting front at 60 min of melting for all the 5
cases analyzed in the study is presented in Fig. 3. The area-weighted average value
Fig. 3 Liquid fraction contours at 60 min. Area-weighted average liquid fraction value of a base
case is 0.76, b case 1: inner zone is 0.91 and outer zone is 0.45, c case 2: upper zone is 0.75 and
lower zone is 0.83, d case 3: inner zone is 0.44 and outer zone is 0.12, e case 4: upper zone is 0.76
and lower zone is 0.80