Air directing arrangement for controlling airflow at an outlet

A rotorcraft comprising a fuselage, a compartment outlet located on the fuselage, and an air directing arrangement that is mounted to the fuselage at the compartment outlet for controlling flow of air in a predetermined flow direction at the compartment outlet, wherein the air directing arrangement comprises:

• a continuous surface with a longitudinal direction that covers the compartment outlet outside the fuselage and forms a flow channel for directing an air flow at the compartment outlet, wherein the continuous surface comprises a plateau segment and two curved segments;
• a first flow-through opening that is formed at a first position of the flow channel between the continuous surface and the fuselage, wherein the first flow-through opening forms an air inlet area;
• and
• a second flow-through opening that is formed at a second position of the flow channel between the continuous surface and the fuselage, wherein the second flow-through opening is arranged downstream of the first flow-through opening in the predetermined flow direction and wherein the second flow-through opening forms an air outlet area;
• wherein the plateau segment is separated from the compartment outlet by a predetermined distance to define respective opening heights of the first flow-through opening and the second flow-through opening, wherein the two curved segments delimit respective opening widths of the first flow-through opening and the second flow-through opening, wherein the opening height and opening width of the first flow-through opening are respectively smaller than or equal to the opening height and opening width of the second flow-through opening, and wherein the air inlet area is smaller than the air outlet area.

An air directing arrangement for controlling flow of air in a predetermined flow direction at a compartment outlet of a fuselage of a rotorcraft, comprising:

• a continuous surface with a longitudinal direction that covers the compartment outlet outside the fuselage and forms a flow channel for directing an air flow at the compartment outlet, wherein the continuous surface comprises a plateau segment and two curved segments, and wherein the continuous surface is formed in the predetermined flow direction with a profile that comprises at a first position an air-foil shaped end section such that the plateau segment is provided with a greater thickness at the first position than at a second position;
• a first flow-through opening that is formed at the first position of the flow channel between the continuous surface and the fuselage, wherein the first flow-through opening forms an air inlet area;
• and
• a second flow-through opening that is formed at the second position of the flow channel between the continuous surface and the fuselage, wherein the second flow-through opening is arranged downstream of the first flow-through opening in the predetermined flow direction, and wherein the second flow-through opening forms an air outlet area;
• wherein the air inlet area is smaller than the air outlet area.