Kari Thunshelle, Thea Marie Danielsen, Sverre Holøs, Mads Mysen
Languages: English | Pages: 9 pp
Bibliographic info:
39th AIVC Conference "Smart Ventilation for Buildings", Antibes Juan-Les-Pins, France, 18-19 September 2018

Use of Demand Controlled ventilation (DCV) can potentially save more than 50% of energy use for ventilation purposes compared to constant air volume (CAV) ventilation. Correct and updated calculation of preset minimum (Vmin) and maximum (Vmax) airflow rates are important to maximize energy saving and to ensure good indoor quality. Furthermore, earlier studies have shown that controlling units' ability to actually handle V min is lacking and causes instability in the DCV systems 
State of the art study of leading Norwegian consulting firms documented that use of advanced Spreadsheet-sheets is the common approach for calculation ventilation rates, where the main focus is on Vmax. This even if use of BIM (Building Information Modeling) is common in this kind of firms.  
Based on this knowledge, we have developed a BIM-integrated Design tool for calculation of ventilation rates. This tool defines a method for using specific data for each space within the model as basis for the calculations. By running different scripts, recommended ventilation rates are easily calculated. The tool can save hours of work and ensure correct values in line with changes done during the design phase. The tool has a built-in check of the VAV-dampers ability to control air flow rates from Vmix to Vmax. This will increase the focus on Vmin, and implemented recommendations are new research-based values. The tool also includes first recommendations on ventilation rates based on CO2 calculations. These calculations will be further developed.