Hybrid Ventilation for Multi-Zone Buildings - Development of Optimal Control Strategies through Experiments and Dynamic Modelling

摘要

Hybrid ventilation represents an interesting option both to guarantee good air quality for indoor environments and to reduce the energy consumption related to the mechanical motivation of the air. In order to join these objectives it is crucial to adopt an efficient ventilation management system. With this purpose, this paper focuses on the optimisation of control strategies for a multi-zone building equipped with a specific hybrid ventilation system, in which mechanical ventilation is provided by a forced flow system while natural ventilation is managed by properly motorized windows. An experimental platform was built in a real building. Also, a previously validated numerical model for the dynamic simulation of the environment was employed to compare three ventilation strategies in terms of the efficiency in removing carbon dioxide. The first strategy consisted of simple natural ventilation, while the remainder were hybrid strategies based on ON/OFF logic and on fuzzy logic respectively. Since the hybrid ventilation technique was found to be more efficient in maintaining good IAQ, the last step consisted in developing and testing an optimised multi-criteria hybrid ventilation strategy aimed at guaranteeing good IAQ with the minimum period of mechanical ventilation. The optimised strategy showed improved control of the CO_2 concentration and a further reduction by 5% of the mechanical ventilation load.