HomeIndustriesProductsServicesEventsAbout Us

Customer Login

Using Region sources in CFD-VisCART

In order to control grid spacing at user-defined locations, mesh sources are a common tool in CFD-VisCART (Figure 1). Point, Line, Curve, Plane, Box and Surface sources have been available for several years. Cylinder and Sphere sources were introduced a few years back. To extend this toolset further, CFD-VisCART V2013.0 introduced Region sources. Unlike the other mesh sources, where shapes are geometric in nature, Region sources can be used with arbitrary shapes. A Region source is a closed region inside which the volume mesh is to be refined. Several Region sources can be defined in the model, and they can be combined with any other sources. At any given location, if several sources are present, the smallest cell size found will be applied.


Image

Figure 1. Source panel in CFD-VisCART


To create a Region source, the first step is to import a surface (or copy/manipulate an existing surface) into the model and tag this surface to be used for Region source specification by right-clicking and checking the box ‘For Region Source Only’ (Figure 2). It can be applied to as many surfaces as desired by the user. These Region source surfaces will not participate in the meshing process other than to identify the Region sources. In the Explorer list, the column ‘For Region Src Only’ indicates which surfaces have been tagged this way (Figure 2).


Image

Figure 2. ‘For Region Source Only’ tag


Next step is to add a Region source marker (usually within the region defined by the above mentioned tagged surface) to completely identify the Region source. CFD-VisCART will find the closed region starting from the given location of this point, similar to the domain marker. To create this marker, in the Source panel, the user should click on ‘Region Source’ (Figure 1). Just like for a domain marker, coordinates for the Region source marker can be either entered directly, or defined relative to a surface using the options ‘Set Behind at Least Away’ or ‘Set in Front of Surface’ (Figure 3).

Finally, the user needs to define the refinement level that will be applied inside the specified region (Figure 3).


Image

Figure 3. Region source definition panel


In the example below, we consider a vehicle in a wind tunnel (Figure 4). The vehicle was scaled up to create 4 nested car-shaped surfaces and relative region sources are specified (Figure 5).


Image

Figure 4. Vehicle model inside wind tunnel and vehicle close-up



Image

Figure 5. Vehicle model and 4 nested scaled-up surfaces


The resulting mesh is shown in Figures 6 and 7. In Figure 6, the effect of an additional box source is also shown, and Figure 7 clearly shows the 4 refinement regions.


Image

Figure 6. Mesh around the vehicle



Image

Figure 7. Mesh close-up near the vehicle


If you have any questions about this feature or would like us to discuss other topics in the future, please let us know.

Regards
Emmaneul Bot
ESI CFD Support Team

 
Buy Sumatriptan onlineThe maximum effect occurs within 2 hours, using a spray after 1.5 hours. Comprar cialis generico Brasil EUA são o único país no mundo reside permanentemente Levitra 20mg comprar en línea Buy drug Gabapentin online
© 2017 ESI Group CFD Portal