584: Advanced Decentralized Ventilation: How Wind Pressure Can Be Used to Improve System Performance and Energy Efficiency

The current paper addresses the problem of existing, highly inefficient ventilation systems with large pressure losses and proposes a new ventilation concept that is in accordance with the lowEx principle. The ventilation system consists of decentralized supply air units and a highly interlaced ducting network. Not only does the conception of this system lead to minimal pressure losses but also allows the wind forces acting on the building to be used for air transportation. Making use of the wind adds additional value to decentralized concepts in that it significantly improves the ventilation performance and reduces the energy costs. In order to assess the air distribution in the ducting network and the ventilation performance a one dimensional steady state analysis was used. The analysis was carried out for a virtual building with a total ventilation rate of 8000 m/h. The steady state analysis showed that in comparison to typical centralized supply system the decentralized system lowers the total fan power demand by a factor larger than 4. Using a 40% overcapacity of fans in the decentralized system leads to a further reduction of fan power demand by almost 25% for the case of wind loading with a wind speed of 10 m/s. The overcapacity of the fans can also be used to decrease cooling load in summer and heating load in winter.