Thermal storage
Phase change materials (PCMs) for thermal storage are available in several forms to suit different applications. In its simplest form, the variations in the cooling load can be provided by the latent heat of fusion of ice or frozen eutec-TIC. Ice can be formed, allowing her to build up on the surface of the evaporator coil in the tank. Brines more, as a rule, are held in closed tanks or plates again condenser coils inside, the outside of the tank formation of secondary heat exchange surface. Eutectics can be formulated depending on the required temperature.
An example of alternative PCM paraffin-based material. The specific heat and latent heat paraffins is about 2.1 kJ/(KGC). They melt enthalpy lies between 120 and 160kJ/kg, which is very high for organic materials. The combination of these two values leads to high energy storage density. Therefore, the latent heat of paraffins/waxes offer four to five times higher heat capacity, by volume or mass, than in water at low temperature that the differences. They have low thermal conductivity, but also for accumulation of heat this can be overcome by introducing enough surface.
Variations have pumped liquid, such as one of glycols, and contain PCM inside the capsule into the tank.
Capsules in the form of plastic balls and PCM can be formulated to meet any required thermal storage temperature.
Associated PCMs include PCM into an existing structure. When the PCM changes in fluid inside the supporting structure, the combined action of capillary forces auxiliary materials and special multifunctional additive ensures that the PCM, even when in the liquid phase, remains within the structure. This means that he always works with the " dry " material and liquid handling problems are eliminated. Free places within associated PCMs allow volume expansion PCM to take place in the...
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Distributed Cooling, Thermal Storage