Ottimizzazione energetica di un impianto di refrigerazione a CO2 transcritica: analisi sperimentale e modellazione impiantistica

This thesis focuses on optimizing CO2 refrigeration systems in response to the Montreal Protocol's requirement to phase out ozone-depleting refrigerants and transition to safer and more environmentally friendly options. The research begins with an analysis of why carbon dioxide is an ideal refrigerant, followed by a review of the current state of research in this field. Experimental activities were then conducted at the University of L'Aquila, where each component of a commercial refrigeration system was carefully analyzed. Several experimental campaigns were carried out to identify the limitations and challenges of the system. Once the experimental data was collected, the energy optimization of the system was performed: a model of the entire system was made using the Gt-Suite software, and subsequently validated with experimental data. This modeling allowed for simulations under various environmental and plant conditions, reducing time and costs compared to the same operations carried out in the laboratory. Finally, the developed model was utilized to evaluate a different system solution to increase performance, with particular reference to the use of an expander.