Better simulations of naturally ventilated buildings
Measuring ventilation rate is crucial to ensuring the control of thermal comfort, energy saving and emission of pollutants in buildings. This is more difficult in naturally ventilated (NV) buildings because of dynamic and complex air flow patterns caused by wind and the buoyancy effects due to differences in temperature. The aim of the HNVR-CALCULATOR (Handy natural ventilation rate calculator based on computational fluid dynamics) project was to develop an easy to use computer fluid dynamics (CFD) simulation for acquiring information about ventilation rate in NV buildings. Project partners created an automated simulation tool aimed at farmers and non-CFD experts, which took into consideration building and ventilating configurations and outdoor wind conditions. The simulation tool, named SYS (simulate yourself) employed user-friendly graphical interfaces and a 3D interactive visualisation module. All SYS modules were automated and the quality of each process controlled. An important advantage was that the SYS was developed using a freely available open-source code. The SYS programme and its documentation are available from the project website. Wind tunnel experiments were used to validate the CFD simulation tool. These showed that air velocities predicted by the CFD tool agreed with measurements obtained from three wind tunnel tests. The effects of different mesh sizes and turbulence models on simulation results were also tested. The SYS programme will enable non-CFD experts to use aerodynamic information to further their business and research needs. The intention of HNVR-CALCULATOR is that its work can be applied to different fields. These include inspiring new research into animal rearing conditions in hot climates, while reducing energy costs. SYS can also be used to predict the spread of infection between buildings and within cities as the result of bioterrorism.
Keywords
Computer fluid dynamics, naturally ventilated buildings, HNVR-CALCULATOR, 3D interactive visualization, wind tunnel, bioterrorism
