This article experimentally studies the thermal performance of latent heat storage in a two-phase thermosyphon solar water heater, which utilizes the superior heat transfer characteristics of boiling and condensation, and eliminates drawbacks found in the conventional solar water heater. Experimental investigations are first conducted to study the thermal behavior of tricosane (paraffin wax 116), water, and sodium acetate $(NaCH3COO∙3H2O)$ used as energy storage materials. The results indicate that tricosane provides many advantages to be the energy storage material in the latent heat storage system. This study also examines the functions of charge and discharge thermal behaviors in a two-phase thermosyphon solar water heater. The results show that the system gives optimum charge and discharge performance under 40% alcohol fill ratio and with tricosane used as the energy storage material, and displays an optimum charge efficiency of 73% and optimum discharge efficiency of 81%.

1.
ASHRAE
, 1999,
Handbook of HVAC Applications
, Atlanta, GA, pp.
32.11
32.14
.
2.
Mao
,
C. L.
,
Chun
,
L. J.
,
Lee
,
W. S.
, and
Chen
,
S. L.
, 2003, “
Thermal Performance of a Two-Phase Thermosyphon Energy Storage System
,”
Sol. Energy
0038-092X,
75
(
4
), pp.
295
306
.
3.
Abhat
,
A.
, 1983, “
Low Temperature Latent Thermal Energy Storage: Heat Storage Materials
,”
Sol. Energy
0038-092X,
30
(
4
), pp.
313
332
.
4.
Esen
,
M.
,
Durmus
,
A.
, and
Durmus
,
A.
, 1998, “
Geometric Design Solar-Aided Latent Heat Store Depending on Various Parameters and Phase Change Materials
,”
Sol. Energy
0038-092X,
62
(
1
), pp.
19
28
.
5.
Sari
,
A.
, and
Kaygusuz
,
K.
, 2002, “
Thermal Performance of a Eutectic Mixture of Lauric and Stearic Acids as PCM Encapsulated in the Annulus of Two Concentric Pipes
,”
Sol. Energy
0038-092X,
72
(
6
), pp.
493
504
.
6.
He
,
B.
, and
Setterwall
,
F.
, 2002, “
Technical Grade Paraffin Waxes as PCMs for Cool Thermal Storage and Cool storage Systems Capital Cost Estimation
,”
Energy Convers. Manage.
0196-8904,
43
, pp.
1709
1723
.
7.
ISO
, 1995,
Guide to the Expression of Uncertainty in Measurement
,
International Organization for Standardization
,
Geneva, Switzerland
.
8.
Wada
,
T.
,
Yamamoto
,
R.
, and
Matsuo
,
Y.
, 1984, “
Heat Storage Capacity Of Sodium Acetate Trihydrate During Thermal Cycling
,”
Sol. Energy
0038-092X,
33
(
3–4
), pp.
373
375
.
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