Convergent divergent exit nozzle for a gas turbine engine

A nacelle for a gas turbine engine, the nacelle comprising:

• a ring shaped structure defining a center axis and having a radially outward surface and a radially inward surface;
• an aft portion of the radially inward surface including an axially extending convergent-divergent exit nozzle;
• and
• an axially extending secondary duct passing through said nacelle in said convergent-divergent exit nozzle, the axially extending secondary duct including an inlet at a convergent portion of the axially extending convergent-divergent exit nozzle and an outlet at a divergent portion of the axially extending convergent-divergent exit nozzle, the axially extending secondary duct including a circumferential ring duct and a plurality of isolated airflow passages, each of the isolated airflow passages extending a partial length of the axially extending secondary duct and contained entirely within the divergent portion of the axially extending convergent-divergent exit nozzle.

A gas turbine engine comprising:

• an engine core and a fan driven by the engine core;
• a nacelle radially surrounding the engine core and the fan;
• a bypass passage including a convergent-divergent exit nozzle, the bypass passage being defined by the nacelle at an outer diameter of the bypass passage and by an outer diameter of the engine core at an inner diameter of the bypass passage, wherein the convergent-divergent exit nozzle includes:
• a primary passage and a secondary passage radially exterior to the primary passage, wherein the secondary passage includes a secondary passage inlet disposed in a convergent region of the convergent-divergent exit nozzle, a secondary passage outlet disposed in a divergent region of the convergent-divergent exit nozzle, a circumferential ring duct, and a plurality of isolated airflow passages, each of the isolated airflow passages extending a partial length of the secondary passage and being contained entirely within the divergent portion of the convergent-divergent exit nozzle.