The performance of thermal solar systems can be enhanced by extending its operational time by the aid of thermal energy storage. In the present work, the transient behavior of packed bed thermal energy storage (TES) was investigated experimentally and numerically. An experimental setup was designed and fabricated to simulate the charging and discharging operational modes of the system. 101 spherical capsules were filled with wax paraffin as PCM and packed in cylindrical container bed of 105 mm diameter and 420 mm long. The processes of the experimented storage system were simulated mathematically and solved numerically by finite difference technique. The analyses were carried out at two different mass velocity of the working fluid. The numerical model described the transient behavior of the system and it was in acceptable agreement with the experimental results. The transient period in the charging mode of the tested storage was around 30 min, while the energy recovery period in the discharging mode was around 60 min. The achieved results demonstrated that the tested TES could be used to enhance the performance of the thermal solar systems. The proposed packed bed thermal energy storage is easy to implement with low cost.

1.
B.
Zalba
,
J. M.
Marin
,
L. F.
Cabesa
, and
H.
Mehling
,
Appl. Therm. Eng.
23
,
251
(
2003
).
2.
A.
Sharma
,
V. V.
Tyagi
,
C. R.
Chen
, and
D.
Buddhi
,
Renewable Sustainable Energy Rev.
13
,
318
(
2009
).
3.
M
Hadjieva
,
S.
kanev
, and
J
Argirov
,
Sol. Energy Mater. Sol. Cells
27
,
181
(
1992
).
4.
B. M.
Gibbs
and
S. M.
Hasnain
, “
DSC study of technical grade phase change heat storage materials for solar heating applications
,” in
Proceedings of the 1995 ASME/JSME/JSEJ International Solar Energy Conference
, Part 2,
1995
.
5.
G. A.
Lane
,
Solar Heat Storage: Latent Heat Material, Vol. II, Technology
(
CRC
,
Florida
,
1986
).
6.
J.
Parkash
,
H. P.
Garg
, and
G.
Datta
,
Energy Convers. Manage
33
(
1
),
51
(
1985
).
7.
N. K.
Bansal
and
D.
Baddhi
,
Energy Convers. Manage.
33
(
4
),
235
(
1992
).
8.
A.
Sharma
,
A.
Sharma
,
N.
Pradhan
, and
B.
Kumar
,
Performance evaluation of a solar water heater having build in latent heat storage unit, IEA, ECESIA Annex 17. Advanced thermal energy storage through phase change materials and chemical reactions—feasibility studies and demonstration projects
.
4th workshop
, Indore, India, March 21–24,
2003
, pp.
109
115
.
9.
D.
Vikram
,
S.
Kaushik
,
V.
Prashant
and
N.
Nallusamy
, “
An improvement in the solar water heating system using phase change materials
,” in
Proceedings of the International Conference on Renewable Energy for Developing Countries
, University of California, Washington, DC,
2006
.
10.
A.
Felix Regin
,
S. C.
Solanki
, and
J. S.
Saini
,
Renewable Energy
34
,
1765
(
2009
).
11.
E.
Talmatsky
and
A.
Kribus
,
Sol. Energy
82
,
861
(
2008
).
12.
E.-B. S.
Mettawee
and
G. M. R.
Assassa
,
Sol. Energy
81
,
839
(
2007
).
13.
M. M.
Alkilani
,
K.
Sopian
,
S.
Mat
, and
M. A.
Alghoul
,
Eur. J. Sci. Res.
27
(
3
),
334
(
2009
).
15.
Z.
Chen
,
M.
Gu
, and
D.
Peng
,
Appl. Therm. Eng.
30
,
1967
(
2010
).
16.
D.
Zhou
and
C. Y.
Zhao
,
Appl. Therm. Eng.
31
,
970
(
2011
).
17.
T.
Saitoh
,
Refrigeration
58
,
749
(
1983
).
18.
J. P.
Coutier
and
E. A.
Farber
, “
Designing rock beds as storage units for solar air systems using an optimized method based on numerical model
,” in
Proceeding of ISES Congress
, Brighton, England, 23–28 August,
1981
.
19.
B.
Carlson
and
G.
Wettermark
,
Solar Energy
24
,
239
(
1980
).
20.
K.
Cho
and
S. H.
Choi
,
Int. J. Heat Mass Transfer
43
,
3183
(
2000
).
You do not currently have access to this content.