Experimental Study on Two PCM Macro-Encapsulation Designs in a Thermal Energy Storage Tank

Abstract

The use of latent heat thermal energy storage is an effective way to increase the efficiency of energy systems due to its high energy density compared with sensible heat storage systems. The design of the storage material encapsulation is one of the key parameters that critically affect the heat transfer in charging/discharging of the storage system. To fill the gap found in the literature, this paper experimentally investigates the effect of the macro-encapsulation design on the performance of a lab-scale thermal energy storage tank. Two rectangular slabs with the same length and width but different thickness (35 mm and 17 mm) filled with commercial phase change material were used. The results show that using thinner slabs achieved a higher power, leading to a reduction in the charging and discharging time of 14% and 30%, respectively, compared with the thicker slabs. Moreover, the variation of the heat transfer fluid flow rate has a deeper impact on the temperature distribution and the energy charged/released when thicker slabs were used. The macro-encapsulation design did not have a significant impact on the discharging efficiency of the tank, which was around 85% for the operating thresholds considered in this study.

Comparative Study of Inlet Structure and Obstacle Plate Designs Affecting the Temperature Stratification Characteristics

“…On the other hand, when the PCM balls were located at the upper position in the tank, they contributed to mixing the water. The implementation of PCM in the storage tank was intensively focused because it could take more advantage of latent heat thermal energy storage than sensible heat storage [16][17][18]. Verez et al [17] designed a PCM slab to investigate the effect of PCM slab thickness on temperature stratification.…”

“…The implementation of PCM in the storage tank was intensively focused because it could take more advantage of latent heat thermal energy storage than sensible heat storage [16][17][18]. Verez et al [17] designed a PCM slab to investigate the effect of PCM slab thickness on temperature stratification. The study found that the thickness of the PCM slab affected temperature stratification, with different magnitudes dependent on the flow rate.…”

An experimental facility for latent heat thermal energy storage units

“…Substantial research on different types of PCMs for hot and cold stores is available in the literature [6], [7]. For instance, the use of paraffin wax has been reported several years ago [8], [9].…”

Advanced Power Generation Using a Nitrogen Turbine Engine Instead of a Conventional Injection Steam Turbine Engine

“…What is more important to be concerned about than those challenges is the cost of production of batteries. However, there is a chance in the future that production costs would be lower as the method of battery production is improved [12][13][14][15][16][17][18][19][20][21][22][23].…”

“…What is more important to be concerned about than those challenges is the cost of production of batteries. However, there is a chance in the future that production costs would be lower as the method of battery production is improved [12][13][14][15][16][17][18][19][20][21][22][23]. Technology Description Basic Process is a theory which describes the thermodynamic cycle for the steam turbine which is known as the Rankine cycle [24][25][26].…”