Ventilation effectiveness of a decentralized mechanical ventilation system: on-site measurements and CFD analysis

The evolution of the building sector, with increased airtightness and reduced leakage in building envelopes, has meant that the presence of mechanical ventilation systems in interior spaces is becoming increasingly important and essential to meet indoor air quality requirements. The advent of decentralized ventilation systems, which have recently emerged on the market, represents a significant development in this field. These systems offer a cost-effective solution by ensuring compactness and reducing installation costs. Therefore, they can be a good solution in both renovations and new constructions. The concept of these systems concerns the air exchange in the room where they are installed, with the air intake and outlet close to each other without the presence of ducts, unlike traditional centralized systems in which the air supply and extraction vents are located in different rooms to favour a uniform air exchange within the building. The present thesis explores the topic of ventilation effectiveness. An analysis of the existing literature on the subject is conducted, and its results are used to study the effectiveness of a decentralized ventilation system. Evaluations are carried out through an experimental approach, involving the generation and measurement of CO2 concentration at different room positions and CFD simulations.