Tezislər / Theses

THE 3
rd
 INTERNATIONAL SCIENTIFIC CONFERENCES OF STUDENTS AND YOUNG RESEARCHERS 
dedicated to the 99
th
anniversary of the National Leader of Azerbaijan Heydar Aliyev
327
change is commonly utilized. The amount of latent heat turning into energy 
can be stored with the help of PCM, which absorbs heat during the melting 
process and releases it during the solidification process. There is a wide 
range of PCMs. However, fatty acids and salt hydrates are offered as two of 
the best option, and a comparison between them regarding conditions will be 
provided.
Fatty acids come from animals and plants' oil, so they are non-toxic and 
resistant to corrosion. Eutectic mixture of pseudo-binary fatty acid systems 
(LA–(MA&SA)) is offered as the most effective fatty acid in the PV as PCM 
according to its chemical and thermal properties. Considering the average 
ambient temperature, the indented melting temperature can be obtained 
using various proportions. [4] 
Lauric acid
Myristic acid 
Stearic acid 
 
 
 
Salt hydrates are another type of inorganic Phase Changing Material in 
which energy storage can be effectively attained. Salt hydrates are 
represented as alloys of inorganic salts (AB) and water having a general 
formula of (AB
×
nH2O). Dehydration and hydration processes of the hydrates 
can be regarded as Phase Changing steps which are also recalled as melting 
and freezing of the material in some sources. These substances dehydrate 
either into another hydrate with fewer water molecules or completely 
anhydrous salt. Having higher density than other PCMs, these materials 
possess high thermal conductivity and latent heat. Their properties of being 
nonflammable, biodegradable, recyclable, and wide melting temperature 
range make these inorganic PCMs valuable for future investigations. Two 
salt hydrates that are under the scope of this research are Lithium Nitrate 
Trihydrate (LiNO
3
.3H
2
O) and Sodium orthophosphate dodecahydrate 
(Na
2
HPO
4
.12H
2
O) which has latent heat of fusion of 296 and 265-281 kJ/kg 
respectively and dehydrate fully with the following equations: 
𝐿𝑖𝑁𝑂 . 3𝐻 𝑂 == 𝐿𝑖𝑁𝑂 + 3𝐻 𝑂
𝑁𝑎 𝐻𝑃𝑂 . 12𝐻 𝑂 == 𝑁𝑎 𝐻𝑃𝑂 + 12𝐻 𝑂
While above mentioned fatty acid eutectic mixture possesses excellent 
thermal and chemical characteristics, its significant constraints are poor 
thermal conductivity, issues with charging and discharging operations, and 
shape stability. The main side effects are the disadvantages of salt hydrates, 
corrosive to metals, instability resulting in phase decomposition, and 

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