An analysis of phase change material as thermal mass

Temperature fluctuations within a building can be attenuated by thermal mass. Adding phase change material (PCM) to thermal mass increases the effective heat capacity during the phase transition. This can anchor the temperature of the mass in a narrow band around the melting point of the PCM, further reducing the temperature swings perceived by occupants of the room. A simple dimensionless model for thermal mass forced by a sinusoidally varying air temperature is developed to calculate the performance of the PCM. The mass temperature satisfies the heat equation, with a temperature-dependent thermal diffusivity, and is solved numerically. For a given PCM, the energy stored and returned to the room, the surface temperature amplitude and the penetration depth of heat pulses into a hypothetical semi-infinite mass can all be calculated as a function of a single dimensionless parameter. For optimal performance, the latent heat of the PCM should be as large as possible, the melting temperature range should be narrow and the thickness of the mass should exceed the penetration depth. The PCM wallboard is shown to be potentially as effective as conventional concrete, so lightweight buildings could enjoy the benefits of thermal inertia commonly associated with heavyweight structures.

[1]  Fredrik Setterwall,et al.  Phase transition temperature ranges and storage density of paraffin wax phase change materials , 2004 .

[2]  A. W. Pratt.  Heat transmission in buildings , 1981 .

[3]  D. J. Fisk.  Thermal control of buildings , 1981 .

[4]  Helmut E. Feustel,et al.  Thermal Performance of Phase Change Wallboard for Residential Cooling Application , 1997 .

[5]  Andreas K. Athienitis,et al.  Investigation of the Thermal Performance of a Passive Solar Test-Room with Wall Latent Heat Storage , 1997 .

[6]  Alessandro Carbonari,et al.  Numerical and experimental analyses of PCM containing sandwich panels for prefabricated walls , 2006 .

[7]  Luisa F. Cabeza,et al.  Review on thermal energy storage with phase change: materials, heat transfer analysis and applications , 2003 .

[8]  Peter Schossig,et al.  Micro-encapsulated phase-change materials integrated into construction materials , 2005 .

[9]  André Bontemps,et al.  Experimental investigation and computer simulation of thermal behaviour of wallboards containing a phase change material , 2006 .

[10]  Mohammed M. Farid,et al.  A Review on Energy Conservation in Building Applications with Thermal Storage by Latent Heat Using Phase Change Materials , 2021, Thermal Energy Storage with Phase Change Materials.

[11]  D. A. Neeper,et al.  Thermal dynamics of wallboard with latent heat storage , 2000 .

[12]  R. J. Kedl,et al.  Wallboard with Latent Heat Storage for Passive Solar Applications , 2001 .

[13]  A. Woods,et al.  On the thermal buffering of naturally ventilated buildings through internal thermal mass , 2007, Journal of Fluid Mechanics.

[14]  S. Argyropoulos,et al.  Mathematical modelling of solidification and melting: a review , 1996 .