Importing an NDF file into TurboGrid involves generating and then loading CAD geometry. For details, see Defining Geometry from Generated CAD: CAD From NDF.

In the NDF file, the specification for the flow path, <flow-path>, can include <cavity-objects> specifications for one or more cavities that form secondary flow paths. Format details are given in Appendix 2: BNF Rule List in the TurboSystem User's Guide.

In order for a secondary flow path to be set up in the Mesh workspace upon importing an NDF file, ensure that each interface and wall boundary that forms part of the outline of the secondary flow path is in its own sketch, and that the sketches collectively form a closed loop.

The following is an example <cavity-objects> specification that could be found in a <flow-path> specification of an NDF file:

<cavity-objects>
		<cavity>
		    <cavity-name>ShrCavity</cavity-name>
		    <cavity-type>Shroud</cavity-type>
		    <boundary-objects>
			<boundary>
			    <boundary-name>Inner</boundary-name>
			    <sketch-reference>SecPassInnerWall</sketch-reference>
			    <boundary-type>Wall</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
			<boundary>
			    <boundary-name>Outer</boundary-name>
			    <sketch-reference>SecPassOuterWall</sketch-reference>
			    <boundary-type>Wall</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
			<boundary>
			    <boundary-name>LE</boundary-name>
			    <sketch-reference>SecPassOpenLE</sketch-reference>
			    <boundary-type>Interface</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
			<boundary>
			    <boundary-name>TE</boundary-name>
			    <sketch-reference>SecPassOpenTE</sketch-reference>
			    <boundary-type>Interface</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
		    </boundary-objects>
		</cavity>
		<cavity>
		    <cavity-name>IGVHubCavity</cavity-name>
		    <cavity-type>Hub</cavity-type>
		    <boundary-objects>
			<boundary>
			    <boundary-name>Inner</boundary-name>
			    <sketch-reference>IGVSecPassInner</sketch-reference>
			    <boundary-type>Wall</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
			<boundary>
			    <boundary-name>Outer</boundary-name>
			    <sketch-reference>IGVSecPassOuter</sketch-reference>
			    <boundary-type>Wall</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
			<boundary>
			    <boundary-name>LE</boundary-name>
			    <sketch-reference>IGVOpeningLE</sketch-reference>
			    <boundary-type>Interface</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
			<boundary>
			    <boundary-name>TE</boundary-name>
			    <sketch-reference>IGVOpeningTE</sketch-reference>
			    <boundary-type>Interface</boundary-type>
			    <manage-opening>false</manage-opening>
			</boundary>
		    </boundary-objects>
		</cavity>
</cavity-objects>