System and method for actively changing an effective flow-through area of an inlet region of an aircraft engine

A fluidic effective flow-through area control system for an inlet region of an aircraft engine, said fluidic control system comprising:

• a blowing system positioned in the inlet region and being configured to blow a stream of air into the inlet region at an angle relative to an inner wall of the inlet region, to generate a fluidic obstruction to the airflow through the inlet region and generate at least one region of separated vortical flow in the airflow through the inlet region;
• and
• a suction system positioned in the inlet region and downstream from said blowing system, wherein said suction system is configured to apply suction to the airflow in the inlet region to reattach, trap and control the region of separated vortical flow.

A variable effective flow-through area inlet of an aircraft engine, said variable effective flow-through area inlet comprising:

• an inner wall defining an airflow passage;
• and
• an upstream wall-flow perturber and a downstream wall-flow perturber connected to said inner wall, said downstream wall-flow perturber being positioned downstream from said upstream wall-flow perturber, and said upstream and downstream wall-flow perturbers being configured to generate and trap at least one region of separated vortical flow in the airflow within the airflow passage.

A method for actively changing an effective flow-through area of an inlet region of an aircraft engine, said method comprising:

• creating at least one region of separated vortical flow in an airflow passage, the airflow passage being defined by the inlet region;
• and
• trapping the region of separated vortical flow in the airflow passage, wherein the region of separated vortical flow partially obstructs a main inlet airflow.

A fluidic method for actively changing an effective flow-through area of an inlet region of an aircraft engine, the inlet region defining an airflow passage, and said fluidic method comprising:

• blowing a stream of air at an angle α, relative to an inner wall of the inlet region, into the airflow passage at a blowing position to generate a fluidic obstruction to the airflow through the airflow passage and create a region of separated vortical flow in the airflow passage;
• and
• applying suction to the airflow in the airflow passage downstream from the blowing position to trap and control the region of separated vortical flow to protect a plurality of fan blades from the impingement of a disturbed airflow, the fan blades being positioned downstream from the inlet region in the aircraft engine.