Fluid Domain Extraction
The first step in the Flow Analysis simulation process is the extraction of the fluid domain from an existing CAD model. Click 
Flow Analysis > 
Create Fluid Domain to create a fluid domain. The Fluid Domain Creation tab opens.
Flow Analysis > Create Fluid Domain to create a fluid domain. The Fluid Domain Creation tab opens.The details in fluid volume extraction are listed below:
• Openings tab—Contains the surfaces and faces that are automatically recognized from the CAD surfaces. For details about the surfaces, click a surface and view the surfaces that appear in the Surface Sets dialog box. To remove existing holes from the domain, right-click the hole and select Remove.
• Domain—For the fluid domain, select Internal from the list.
• Add to Simulation—Automatically adds the extracted domain as a fluid domain for the simulation.
• Shrinkwrap—Merge components during the fluid domain extraction. In some cases, if the normal merge approach fails to create the fluid domain, you can use the shrinkwrap option.
• 
—Preview or Regenerate fluid domain
—Preview or Regenerate fluid domain• 
—Apply the selected extraction
—Apply the selected extraction• 
—Exit
—ExitFluid domains appear under Domains in the Flow Analysis Tree.
Splitting Domains
Select a domain and then in the Simulation Domains group click 
Split Domain to split an extracted fluid domain.
Split Domain to split an extracted fluid domain.A fluid domain is split for the following reasons:
• To separate a rotating or moving volume from a stationary volume.
• To separate two stationary or rotating volumes.
Planar or cylindrical splits are performed on the extracted domain.
To split the domain, follow the steps listed below:
1. In the Model Tree select the extracted domain.
2. Select the Split type as Plane or Cylinder:
◦ Plane—Specify the plane for the split and set the Offset value.
◦ Cylinder—Specify the plane for the split, and set Center point and Radius. Select Default or Custom for the coordinate system. When you select Custom, the Coordinate System dialog box opens where you specify the reference coordinate system.
3. Click 
to change the side that appears for the split operation.
to change the side that appears for the split operation.4. Click . The split domains appear in the Model Tree.
. The split domains appear in the Model Tree.