A combustion turbine includes a compressor section, a combustion section downstream from the compressor section, and a turbine section downstream from the combustion section. A diffuser section is downstream from the turbine section and has an outer wall, an inner wall, and at least one strut member extending therebetween. The outer wall has at least one first gas passageway therein, the inner wall has at least one second gas passageway therein, and the at least one strut member has at least one third gas passageway therein. The at least one first, second and third gas passageways deliver gas therethrough to assist attachment of a boundary layer to adjacent surfaces of the outer wall, the inner wall, and the at least one strut, respectively.