Diffusers, diffusion systems, and methods for controlling airflow through diffusion systems

A diffusion system for coupling an air flow from a centrifugal compressor to an axial combustor, the system comprising:

• a diffuser for receiving the airflow from the centrifugal compressor, the diffuser including:
• a first wall having a radially-extending section and a curved section,
• a second wall having a radially-extending section and a curved section, the radially-extending section and the curved section of the second wall spaced apart from the radially-extending section and the curved section of the first wall such that the curved section of the second wall is disposed radially inwardly from the curved section of the first wall and a flow path is defined therebetween, and
• a first plasma actuator disposed on the curved section of the second wall, the first plasma actuator adapted to generate a first electric field to ionize a first portion of air flowing along the flow path to thereby form a plurality of ionized species capable of inducing a second portion of air to flow in a desired direction;
• and
• a deswirl assembly in flow communication with the diffuser to provide the airflow from the diffuser flow path to the axial combustor.