To increase the thermal conductivity of organic fatty phase change material (PCM)

different mass fractions of nanoparticles with high thermal conductivity

including 10?30-nm copper powder

alumina

and iron oxide

were individually added to composite PCMs of capric/caprylic acid (with a 30:70 mass ratio). The experimental results show that the composite PCMs exhibit good thermal stability and zero precipitation after the addition of nanoparticles at a mass fraction of 0.1?0.4%. Compared with the original material

the thermal conductivity is greatly improved by 5.1%-6.5%

4.0%-12.4%

6.7%-17.5%

for the copper powder

alumina

and iron oxide

respectively. The fluctuation range of the phase change temperature is small (±0.39℃). The phase change latent heat varies little and the increase range is 2.2%-5.5%. Therefore

the selection of appropriate amounts of nanomaterials can improve the thermal properties of the original PCMs

which may have wide potential application.