Abstract: A method for assembling a gas turbine engine includes coupling a rotor assembly including a plurality of rotor blades about a rotatable main shaft of the gas turbine engine. The main shaft is aligned in an axial direction of the gas turbine engine. A shroud assembly is coupled to the gas turbine engine. The shroud assembly includes a plurality of shroud segments circumferentially coupled about the rotor assembly such that a shroud spacing gap is formed in the axial direction between adjacent shroud segments. A cooling fluid source is coupled to each shroud segment such that cooling fluid is channeled through each shroud segment into a corresponding shroud spacing gap to facilitate positive purge flow through the shroud spacing gap.