Heat transfer and dynamics characterization of porous structures for high-density adsorption storages

Adsorption storage is considered a promising alternatives both in industrial and residential applications. One of limiting factors for the application in buildings is the need for compact and efficient systems, with high energy density. To this aim, the realization of porous structures (e.g. metal or polymeric foams) for zeolite synthesis or embedding has to be evaluated. Different metal foams, realized in AlSi7 alloy with different pore densities and thicknesses were realized and experimentally tested in order to define the most suitable ones for heat storage applications. At first, morphology characterization of the materials through an optical microscope was carried out. Subsequently, heat transfer capacity was evaluated by means of a self-developed apparatus at CNR-ITAE, which makes use of Peltier cells for cycling the foam samples, while the temperatures in different part of the foams is measured. By means of cycles with different amplitudes and length, the effect of pore size and thickness of the sample was evaluated. Dynamic characterization of the coated foams was carried out by means of a gravimetric Large Temperature Jump apparatus at CNR-ITAE. Finally, a numeral model was realized in COMSOL Multiphysics and validated against experimental results, that was subsequently used to define an "equivalent" material that can be used for dynamic simulation of a complete adsorption storage system.