Experimental Characterization and Numerical Simulation of a Low-Scale Personal Cooling System with Integrated PCM

Abstract

Phase Change Materials (PCMs), among the existing thermal storage technologies, are characterized by higher storage densities than conventional storage systems, and absorb and release thermal energy at nearly constant temperatures. In recent years, the potential advantages that can be obtained by the integration of these materials into refrigeration machines have attracted the attention of specialized literature. Indeed, PCMs can allow a more efficient operation through an appropriate increase in thermal inertia, for applications relative to air conditioning in both internal residential environments and inside vehicles for the transport of people, and also in the case of machines used in the field of food refrigeration. Furthermore, in recent years, innovative solutions with integrated PCM have also been analyzed, aiming at enhancing the usability and transportability of refrigeration systems, as well as increasing the energy efficiency and reducing environmental impact. In this context, the present work focuses on the experimental characterization and numerical simulation of a cooling system with integrated PCM. In particular, the cooling system, designed for a personal cooling application, is experimentally analyzed by varying the configuration of the PCM-based condenser, while the numerical simulations have been realized to validate a simulation tool that could be used for the design and optimization of the PCM condenser configuration. The results allow us to identify the main characteristics of the analyzed personal cooling system, namely, the cooling capacity and operating autonomy, and to point out the utility and the limits of the developed simulation tool. Among the various configurations analyzed, the best one in terms of refrigeration power and autonomy is the one characterized by the highest heat transfer surface of the heat exchanger, with the refrigerant compressor at 50% power.