초록 ▼

An aerodynamic low drag structure (12) has a skin (18, 19, 20) which in movement of the structure (12) relative to a surrounding gaseous fluid medium produces at a flow control region of the skin (18) laminar flow in a boundary layer adjacent the skin. To improve boundary layer control, gaseous flui

An aerodynamic low drag structure (12) has a skin (18, 19, 20) which in movement of the structure (12) relative to a surrounding gaseous fluid medium produces at a flow control region of the skin (18) laminar flow in a boundary layer adjacent the skin. To improve boundary layer control, gaseous fluid is withdrawn from the boundary layer at the flow control region into a first inlet opening (21, 22, 23) in the skin (18) and is conveyed along a first fluid flow path (241, 242) within the structure (12) for discharge at a discharge opening (28) downstream of the first inlet opening (21, 22, 23). Gaseous fluid is withdrawn at a second inlet opening (26) in the skin (20) at a region of the skin subjected to gaseous fluid at ramming pressure and conveyed along a second fluid flow path (27, 242) within the structure to the discharge opening (28) or a further discharge opening. Fluid under ramming pressure in the second fluid flow path (27, 242) causes the fluid in the first fluid flow path (241, 242) to be impelled along the first fluid flow path thereby causing fluid to be withdrawn from the boundary layer and to be discharged from the discharge opening (28).

대표청구항 ▼

[ I claim:] [1.] An aerodynamic low drag structure which has a skin and which in movement of the structure relative to a surrounding gaseous fluid medium produces at a flow control region of the skin laminar flow of the gaseous fluid in a boundary layer adjacent the skin, characterised by the provis

[ I claim:] [1.] An aerodynamic low drag structure which has a skin and which in movement of the structure relative to a surrounding gaseous fluid medium produces at a flow control region of the skin laminar flow of the gaseous fluid in a boundary layer adjacent the skin, characterised by the provision of a first inlet opening in the skin in the flow control region, first gaseous fluid conveying means within the structure by which fluid withdrawn from the boundary layer into the first inlet opening is conveyed along a first fluid flow path within the structure for discharge from the structure at a discharge opening downstream of the first inlet opening, a second inlet opening in the skin of the structure in a gaseous fluid ram region of the skin in which the skin is subjected to gaseous fluid of the surrounding medium at a predetermined ramming pressure, second gaseous fluid conveying means within the structure in which gaseous fluid under ramming pressure is conveyed from the second inlet opening in the skin along a second fluid flow path within the structure to the discharge opening or a further discharge opening and impelling means so positioned and arranged that the flow of fluid under ramming pressure in the second fluid flow path causes the fluid in the first fluid flow path to be impelled along the first fluid flow path from the first inlet opening to the discharge opening thereby to cause fluid to be withdrawn from the boundary layer in the flow control region and to be discharged from the discharge opening;an aero engine nacelle, the skin defining a nacelle skin having an outer skin portion which produces at the flow control region thereof laminar flow of air in a boundary layer adjacent the outer skin portion and an inner skin portion which defines an air intake duct for the flow to intake air, wherein the first inlet opening is provided in the outer skin portion at the flow control region thereof.