Ah... no, AFAIK no.
When the "model" comes from an outside mesher, you don't in fact import any "model", just the "FE" portion of it. So the areas, lines, keypoints, volumes, are lost forever.
BUT... if you defined the Named Selections PREVIOUSLY, say in Workbench or ICEM or Fluent or CFX, then these WILL be transfered to Ansys with some rules: for example, a Named Selection made of Areas will be automatically "converted" into a Component made of NODES (and this is what you need, indeed), a selection made of Solids will result in a component made of elements, etc. These "conversions" should be described somewhere in the Help.
If you can't define Components / Named Selections at all, then you will be obliged to use some kind of selection based on coordinates or particular attributes...
Regards