What is CFD?

Computational Fluid Dynamics (CFD) analysis is used by building environmental designers to calculate the temperature, velocity and other fluid properties through a 3-D domain. This powerful design tool is used to answer design questions such as:

• What sort of temperature distribution could I expect in an atrium under clear sky summer conditions?
• Will the arrangement of supply diffusers provide adequate air movement?
• Is the location of the radiators going to provide good comfort conditions?
• Will natural ventilation provide occupants with adequate comfort in the summer?
• What effect will the shape of the building have on local wind velocity?
• Are there any regions of stale air inside the building?

DesignBuilder 3-D CFD

DesignBuilder CFD has been especially designed to provide data on airflow and temperature distribution in and around buildings using the same methods as the general purpose pure CFD packages, but at a fraction of the cost and without the need for specialist knowledge.

Using conventional CFD packages for building airflow analysis can be a time consuming task requiring very careful attention to setting up the correct geometry and boundary conditions. Using CFD in DesignBuilder simplifies this process hugely by automatically providing the geometry and boundary conditions. Temperatures, heat flows and flow rates previously calculated by EnergyPlus can be seamlessly used to provide boundary conditions simply by specifying the time/date of the CFD analysis.

The CFD interface has been designed to enable virtual ‘push-button’ CFD analysis from automatically generated rule-based default data, with options to allow more experienced or interested users to modify this data as required. Adopting this approach enables users to obtain realistic 3-D results without having any specialist CFD knowledge.

Some of the key DesignBuilder CFD features:

• 3-D CFD grids are generated automatically from model geometry and boundary conditions to promote optimal solution convergence.
• The CFD engine has been developed around the SIMPLER algorithm, which belongs to one of the most widely used families of CFD solution methods. Turbulence can be modelled using the widely researched and documented k-e model and there are plans to introduce additional models for specific applications.
• The interface incorporates tools to enable a wide range of boundary conditions such as supply diffusers, extracts, temperature patches, etc. to be assigned to room surfaces. A component library is also provided to enable radiators, fan-coil units, furniture, occupants, etc. to be located anywhere within the model and automatically incorporated within the analysis.
• Boundary conditions can be automatically assigned from a previous EnergyPlus simulation.
• 3-D CFD results are displayed using the DesignBuilder OpenGL graphics engine providing impressive, easy-to-interpret images and movies of velocity vectors, temperature contours, iso-surfaces, particle streams, etc.
  

The high quality output provided by DesignBuilder CFD will help you to communicate your results to clients in a visual way that they can really understand.

  

Availablity

DesignBuilder CFD can be purchased either as a standalone module or as part of the Advanced Simulation package.The CFD module can be purchased from the bottom of the main purchase page .