Following on from our previous post describing the Designs & Calculations stage, we then proceed to a full analysis and in some cases prototype testing, to ensure the solution meets your requirements and performs under various environmental conditions.
CFD Analysis
Natural ventilation is crucial for conserving the energy, reducing carbon emission, and improving the comfort level of the built environment and the indoor air quality. Vision Ventilation’s Computational Fluid Dynamics (CFD for short) represents the combination of the modern fluid dynamics, numerical mathematics and computer science. By employing CFD wind environment simulation technology, we can provide you with accurate project information, intuitively describing how the building wind environment breaths under various product designs and air flow characteristics.
Our CFD analysis looks at the architectural design and the building, we then conduct analysis in combination with knowledge of its surroundings and local weather conditions and the product to be used. The CFD wind environmental simulation covers three aspects; site planning, building shape and building envelope, we then superimpose our bespoke ventilation strategy and architectural design to identify strengths and weaknesses. Fine tuning the model ensures the ventilation flow rates provide a robust optimal natural ventilation system that works year-round automatically adjusting to changes in weather conditions.
CFD Product testing
A louvre and damper model are produced to show how air flows through the product. The external louvre is a fixed product with a modulating volume control damper fitted to the back. We model the assembly under different wind pressures and speeds from fully closed, partially open to fully open. As air passes through we can predict resistance and velocity air flows to design the correct amount of ventilation area to maintain comfortable CO2 and temperature internal conditions.
Building layout and air flow characteristics
Using the product CFD results we superimpose these into a model of the building along with wind data for the local surroundings. The results identify how the air moves through the building identifying hot and cold spots and areas where the air movement stagnates. This data allows us to alter the ventilation equipment areas and locations to provide constant and predictable air flow under all seasons and weather conditions.
Prototype Testing
On certain projects we take the CFD model results and construct either scale models of the natural ventilation units or full-size prototypes that we independently test for performance and acoustic properties prior to the main manufacturing process.
Full size prototype mock-up to measure wind loading, acoustics and air flow:
Video of wind tunnel testing at Farnborough Royal Aircraft Testing Facility, Building Q121, 24 foot Wind Tunnel: