Studies on performance enhancement of heat storage system with multiple phase change materials

2021 ◽  
pp. 103585
Author(s):  
Wei Li ◽  
Yuli Zhang ◽  
Xu Zhang ◽  
Jun Zhao
2019 ◽  
Vol 182 ◽  
pp. 508-519 ◽  
Author(s):  
Dong Ho Shin ◽  
Jinsoo Park ◽  
Sung Ho Choi ◽  
Han Seo Ko ◽  
Sarng Woo Karng ◽  
...  

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 942 ◽  
Author(s):  
Rodrigo Fuentes-Sepúlveda ◽  
Claudio García-Herrera ◽  
Diego A. Vasco ◽  
Carlos Salinas-Lira ◽  
Rubén A. Ananías

The incorporation of phase change materials (PCM) in construction components has become an alternative to reduce the effect of thermal loads in buildings with low thermal inertia. This study put together the effective heat storage capacity of an organic phase change material (O-PCM, octadecane) with the construction and production potential of Pinus radiata in Chile. The wood is impregnated with octadecane by using the Bethell method, showing that it has good retention of the impregnator, and that its size was not modified. Differential scanning calorimetry analysis (DSC) showed that the composite material could achieve fusion enthalpy values from 36 (20.8 MJ/m3) to 122 J/g (108.9 MJ/m3). The transient line heat source method used, indicated that impregnation of Pinus radiata with octadecane increases its specific heat at temperatures from 15 to 20 °C, while its thermal conductivity decreases in the radial and the tangent directions, and increases in the longitudinal direction, showing a decrease in the orthotropic behavior of the wood. The ability of Pinus radiata wood to store latent heat positioned it as a candidate material to be considered in the building industry as a heat storage system.


2009 ◽  
Vol 40 (3) ◽  
pp. 25
Author(s):  
Claudio Caprara ◽  
Giovanni Stoppiello

In order to use solar radiation as thermal energy source, heat storage equipments result necessary in each application where continuous supply is required, because of the natural unsteady intensity of radiation during the day. Thermal solar collectors are especially suitable for low temperature applications, since their efficiency decreases when an high inlet temperature of fluid flowing through them is established. On the other hand, low temperatures and low temperature gaps, above all, make very difficult to use traditional sensible heat storing units (water tanks), because of the very large amounts of material required. In this work, a traditional sensible heat storage system is compared with a latent heat storing unit based on phase change materials (PCMs). As a case study, a 840 m3 greenhouse heating application was considered with an inside constant temperature of 18°C. It is thought to be heated by using single layer plate thermal solar collectors as energy source. Inlet temperature of the collectors fluid (HTF) was fixed at 35°C (little higher than melting temperature of PCMs) and a constant flux of 12 l/m2 hour was established as technical usual value. At these conditions, 215m2 solar panels exposed surface resulted necessary. The sensible heat storage system considered here is a traditional water tank storing unit equipped with two pipe coils, respectively for heat exchanges with HTF from collectors and water flux for greenhouse heating. Available DT for heat exchange is estimated as the difference of minimum HTF temperature (in outlet from the collectors) and the required water temperature for greenhouse heating. The latent heat storing unit is instead a series of copper rectangular plate shells which a phase change material is filled in (Na2SO4⋅10H2O). Heat transfer fluids flow through thin channels between adjacent plates, so that a large heat exchange available surface is achieved. The developed computational model (Labview software) permits to superimpose heat exchanges daily curves between heat storing materials and heat transport fluids (for both of the fluids and the heat storing equipments) on the energy supply/demand ones, respectively calculated on the basis of greenhouse energy demand and solar collectors dimensions, characteristics and efficiency. In this manner, units design is achieved by changing thermal energy storing units dimensions, in order that the corresponding heat exchange curves coincide with the previously calculated ones. Successively, among all the possible configurations, the ones showing lower units volumes and less amount of storing materials are chosen as the optimal design solutions. It has been proven that PCMs materials are much more suitable for low temperature applications than sensible heat storing materials (water). In the case of water tank, an about 15.8m3 total volume is required while for PCMs equipment the total volume of storing unit is reduced to about 2.2 m3, such as about seven times total volume less. Besides, according to the simplified and steady state model calculations, PCMs unit shows a better response to the hourly energy fluctuations of solar collectors and greenhouse demand than water tank unit. This is especially due to the high available exchange surface achieved in proposed arrangement.


2015 ◽  
Vol 798 ◽  
pp. 200-204
Author(s):  
Sandesh Bhaskar ◽  
Waqar Ahmed Katib ◽  
D. Senthilkumar

Phase Change Materials (PCM) are used widely in passive heat storage system due to their high heat retention capacities. In the present work an attempt is made to use the PCM as an effective replacement to conventional EGR cooler. The prime advantages of using PCM as an alternative to the traditionally used EGR coolers are that, the pumping operation will no longer be a continuous process hence the power consumed by pumps would drastically reduce, so does the load on the engine and secondly there would be significant reduction in the weight of the system which would ultimately boost the fuel economy of the vehicle. The PCM candidate chosen for study is a Salt blend (59%KF+29%LiF+12%NaF). The chosen specimen's thermal performance is computed based on the duration for which the refrigerant pump remains idle. Using numerical simulation the melting period of PCM(Salt Blend) is computed and the simulation is verified by already established numerical and experimental results for a different material, Rubitherm (RT-42).


2021 ◽  
Author(s):  
Zunaidi Ibrahim ◽  
Stephen Newby ◽  
Vahid Hassani ◽  
Seri Rahayu Ya’akub ◽  
Shahriman Abu Bakar ◽  
...  

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