MAIN FUNCTIONALITY
Wind Simulation using GIS Database
Airflow Analyst can make direct use of terrain and building shape data, which are widely used as part of GIS data, enabling it to create simulations straight away without the need to convert modeling data or do any remodeling as required by traditional fluid dynamics software. The software supports ArcGIS' raster data and TIN data in order to represent elevation data.
In terms of building data, Airflow Analyst supports polygon features with height information as data attributes, as well as multipatch feature classes. Hence, it is able to make use of a wide variety of data, from simple buildings represented as extrusion models, to more complex building shapes generated using a commercial 3D modeler or the ESRI City Engine.
(*Read-in and display of data is provided by the ArcGIS 3D Analyst Extension functionality.)
Generating a Computational Mesh with an Intuitive Operational Environment
In airflow simulation, you create a 3D mesh known as a computational mesh, and the level of detail of that mesh affects the accuracy of the calculation results. Airflow Analyst uses 3D images on a map to display the computational mesh being generated, changing interactively based on the configuration changes made by the user. The software enables the user to adjust the mesh configuration while verifying in 3D the granularity of the mesh intervals for the range, terrain, and physical features of the calculation area.
Advanced Non-stationary Analysis on a PC using LES
Airflow Analyst has an embedded LES (Large Eddy Simulation) solver, capable of producing reliable simulations of airflow movements as they change in complex patterns over time. LES is an algorithm known to need an extremely long time for making its calculations; however, the LES used for Airflow Analyst has been optimized for multi-core CPUs, producing results only in a few hours even on a generic PC.
In addition, if you use a PC with a GPU that specializes in fast operations, you can achieve calculation speeds that are several times faster than a standard CPU. The software allows designers to verify airflow movements in a short period of time, enabling them to focus on creating designs and solving problems while taking into account the effect of the wind.
Easy-to-understand Presentation/Visualization
TBy developing our own expansion of ArcGIS 3D Analyst's display functionality, we were able to implement the visualization of a variety of fluid phenomenon. The display area can be presented on a map in an interactive way using 3D animation, making the flow structures easy to understand.
The analysis results can also be processed statistically or converted into feature classes, so you can use them for spatial analysis and evaluations-a specialty of ArcGIS-, as well as for outputting and sharing them as a map.
Statistical Information Output
Airflow analyst produce non-steady results that change over time. The software makes quantitative analyses of the various values that change over time, such as wind speed or gas concentration, enabling you to do statistical processing of sequential variables.
As part of the statistical processing done after the simulation, the software can calculate and output the average values, maximum values, minimum values, and standard deviations of a variety of variables for each mesh point.
(The picture on the right shows an example of wind speed distribution averaged over time.)
Penetration Wall Configuration
Trees, windshield nets, and the like, weaken the wind by allowing it to penetrate through them. Airflow Analyst can imitate a penetrating wind by assigning the properties of a penetration wall to various shapes on a map. This allows the software to create simulations that take into account the effect that trees, windshield nets, and the like, may have on a windy environment.
Diffusion and Thermal Convection Simulation
Airflow Analyst is able to analyze how certain substances, such as gas emitted from a diffusion source, could be dispersed to its surroundings by wind, providing information such as diffusion ranges and concentration levels.
In addition, by setting the surface temperature of the ground or physical features, it can also simulate the behavior of the wind while taking into account the convection phenomenon, by configuring them as heat sources.