DesignBuilder is built around the EnergyPlus data requirements
EnergyPlus is the U.S. DOE building energy simulation program for modelling building heating, cooling, lighting, ventilating, and other energy flows.
It builds on the most popular features and capabilities of BLAST and DOE-2 but also includes many innovative simulation capabilities such as time steps of less than an hour, modular systems and plant integrated with heat balance-based zone simulation, multizone air flow, thermal comfort, and photovoltaic systems.
EnergyPlus is a stand-alone simulation program without a ‘user friendly’ graphical interface – which is where DesignBuilder comes in. We have integrated EnergyPlus tightly within the DesignBuilder environment to allow you to carry out simulations without any fuss – just define your building model, request data and let the EnergyPlus simulation engine take care of the details.
DesignBuilder has been specifically developed around EnergyPlus allowing most of the EnergyPlus fabric and glazing data to be input. Databases of building materials, constructions, window panes, window gas, glazing units and blinds are provided.
HVAC is modelled using either the “ideal loads” option or the Compact HVAC (now called “HVAC Template”) descriptions provided by EnergyPlus. These allow a number of predefined HVAC system types to be defined parametrically without the need for complex system layouts. These compact descriptions are automatically expanded behind-the-scenes into full HVAC simulation data sets prior to simulation.
There is a range of EnergyPlus simulation engines to choose from including the current DOE executable release, the current DLL release and any interim releases made available by DOE. If you have built your own version of EnergyPlus you can even run this from within DesignBuilder. You can also carry out DesignBuilder simulations via EP-Launch.
DOE EnergyPlus website
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. CFD is used to answer design questions such as:
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:
The high quality output provided by DesignBuilder CFD will help you to communicate your results to clients in a clear visual way that they can really understand.
DesignBuilder CFD has been independently tested against Pheonics, one of the most powerful and widely respected general purpose CFD packages available. The validation work, carried out by Northumbria University, shows that DesignBuilder is able to reproduce the same results as Pheonics given the same input data. This adds to confidence in the results produced by DesignBuilder CFD.
You can view recorded demonstrations of the DesignBuilder CFD software on the Webinars page. These show how DesignBuilder EnergyPlus surface temperature and airflows results can be fed into CFD as boundary conditions and also how DesignBuilder CFD for can be used as part of the HVAC design process.
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 products page .
DesignBuilder provides interoperability with BIM models through its gbXML import capability. This allows you to import 3-D architectural models created in Revit, ArchiCAD or Microstation (and other 3-D drawing systems that support gbXML data exchange) to provide heating and cooling system sizes and environmental performance data in the most efficient way possible.
Revit users can access DesignBuilder while working on their BIM models through the DesignBuilder Revit Plugin. This allows the model to be checked and analysed without leaving Revit.
An important feature of DesignBuilder gbXML import is the removal and repair of gaps between zone inner volumes, which means that models lose very little geometric information in the transfer from CAD to DesignBuilder. In fact, the imported and rendered DesignBuilder model may look more realistic than it did in the CAD software! An example of a rendered image imported from ArchiCAD is shown below.
Import from SketchUp
Greenspace Reseach offer the gModeller plugin for SketchUp that allows 3-D models created in SketchUp to exported as gbXML and imported into DesignBuilder.
DesignBuilder visualisation generates stunning realistically rendered images with the absolute minimum of effort on your part. Rendered images can be obtained at any stage of the model creation process simply by clicking on the Visualisation tab.
The underlying DesignBuilder model contains all the necessary information on building geometry, construction and materials and each material has a photorealistic texture associated with it.
Feature highlights are:
Example rendered images
Above right Dallas Power & Light West Tower by Jason Gentry, Oklahoma State University
Exaltis Tower by Valentin Grimaud a new DesignBuilder user from France
5 School Lane, House by Rowan Tindale, DesignBuilder, UK
Torre de Ingenieria, DesignBuilder model by David Barrera, Mexico
Villa Pifferi, Italy by Roberto Salimbeni, Evolvente
New Hospice, Bucks, UK By Colin Lillicrap, CLA, UK
Uffici Sat by Roberto Salimbeni, Evolvente, Italy
You can display a Sunpath diagram for the building at its current location by checking the Show Sunpath diagram Display option and pressing the Apply button. This will display a Sunpath diagram similar to that shown below.
The Sunpath diagram provided in DesignBuilder can be a very useful way to view the paths taken by the sun as it moves through the sky at all times of the year.
Sunpath diagram scale factor
There is an option to override the default scale factor applied to the Sunpath diagram. With a scale factor of 1 the Sunpath diagram fits snugly round the building. The default scale factor is 1.5.
Sunpath day of month
By default DesignBuilder uses the first day of the month when generating the sunpath lines for each month of the year. This option allows you to use any other day of the month from 1 to 28.
Change solar position tool
When both the Show Sunpath diagram and Show shadows Display options are set, the Change solar position tool becomes available. This allows you to move the sun around the diagram. To do this first click on the Change solar position toolbar icon (above). When this tool is active the cursor become a cross and you can use it to click on a junction of time/month sunpath lines to set the new solar position. You can continue to move the sun around the sky by clicking on the diagram in the same way. An alternative way to use this tool is to drag the sun around the sky. You will notice that the Time of day and Month data in the Display options panel are updated along with shadows as the sun moves through the sky.
You can export your 3-D DesignBuilder models for further daylighting, visualisation and other analysis using the free version of Google SketchUp as an intermediate step.
All of the models on this page were created in DesignBuilder, exported in 3-D DXF format using the ‘Whole model with details’ option and imported into Google SketchUp where details such as textures, trees, people and shading were added.
Image above created from a DesignBuilder model courtesy of Mario Butera (architect Mario Occhiuto)
The 4 models below are located in Ahmedabad, India and were created by Jigisha Adhwaryu, CEPT University, India
DesignBuilder provides 3 types of daylighting calculations:
Daylight Contour Plots and Daylight Factor Calculations
The daylighting simulations available in DesignBuilder v3 allow you to calculate daylight factors and illuminance data using the Radiance daylight simulation engine. The main DesignBuilder daylighting features are:
Example LEED NC2.2 report
For the first time, the advanced HVAC features in EnergyPlus are accessible to the building simulation community in a user-friendly graphical environment.
DesignBuilder v3 now provides a powerful and flexible interface to most EnergyPlus HVAC system types. It is possible to model both air and water sides together in full detail with a good range of components including all ASHRAE 90.1 baseline HVAC systems.
HVAC features include: