11 PCM-Metal Foam Composite Systems for Solar Energy Storage
219
Table 11.3 Thermo-physical
properties of paraffin and
naphthalene
Property
Paraffin
Naphthalene
Latent heat (kJ/kg)
169
147.7
Thermal conductivity (W/m K)
0.2
0.132
Specific heat (J/kg K)
2100
1563
Density (kg/m 3 )
880
976
Melting temperature (K)
335
353
11.5.2 Effect of Foam Material
For this comparison, two different cases are considered—one with aluminum foam
and the other with copper foam. The thermo-physical properties of copper is specified
in Table 11.2. All the other parameters, such as porosity, pore size, PCM and domain
size are kept same as that mentioned in Table 11.1. Figure 11.3 shows the temperature
contours for the two systems at time t = 500 and 1000 s. It can be seen that for
the copper foam system the temperature evolution is faster. This is because of the
Fig. 11.3 Temperature contours at the mid-section. a Aluminum foam at t = 500 s. b Aluminum
foam at t = 1000 s. c Copper foam at t = 500 s. b Copper foam at t = 1000 s
219
Table 11.3 Thermo-physical
properties of paraffin and
naphthalene
Property
Paraffin
Naphthalene
Latent heat (kJ/kg)
169
147.7
Thermal conductivity (W/m K)
0.2
0.132
Specific heat (J/kg K)
2100
1563
Density (kg/m 3 )
880
976
Melting temperature (K)
335
353
11.5.2 Effect of Foam Material
For this comparison, two different cases are considered—one with aluminum foam
and the other with copper foam. The thermo-physical properties of copper is specified
in Table 11.2. All the other parameters, such as porosity, pore size, PCM and domain
size are kept same as that mentioned in Table 11.1. Figure 11.3 shows the temperature
contours for the two systems at time t = 500 and 1000 s. It can be seen that for
the copper foam system the temperature evolution is faster. This is because of the
Fig. 11.3 Temperature contours at the mid-section. a Aluminum foam at t = 500 s. b Aluminum
foam at t = 1000 s. c Copper foam at t = 500 s. b Copper foam at t = 1000 s