Here's the deal, I'm modelling a cylindrical pressure vessel, and I need to apply loads and boundary conditions to the location where it is supported, hence I need to know how to apply the conditions only to the 2 arc areas related to the supports.
Didnt quite understood your question.
But did you try slicing the geometry in design modeler?
Slice it such that you have a seperate body in the area you need to apply loads/constraints to.
Create a nodal named selection and then apply nodal pressure. This way of defining loads is equally valid in workbench and mapdl, at least in ansys 15.