Abstract: A micro-cavity passive actuator is configured to delay dynamic stall of an airfoil. The micro-cavity actuator is formed in the pressure sidewall surface proximate the leading edge of the airfoil. This cavity remains essentially inactive at low incidence. However, as the wing's effective angle of attack dynamically increases and the stagnation point displaces past the micro-cavity, the accelerating flow grazing the cavity induces a high-frequency resonance phenomenon (known as Rossiter modes). The self-generated small-scale disturbances are carried around the leading-edge through the boundary layer to the wing's upper side where the laminar separation bubble (LSB) amplifies these disturbances. This process delays LSB bursting and dynamic stall. The micro-cavity must be sized such that its naturally emitting oscillations are in a range of frequencies that can be amplified by the LSB.

Abstract: A method for inspecting assembly of components in a structure includes acquiring a visual representation of at least a portion of the structure, and saving an electronic file of the visual representation on a computer readable medium. A three-dimensional design of the structure, which contains information on a proper position of the components within the structure, is accessed. The visual representation is compared with the three-dimensional design using a computer, and a feedback indicating a result of the comparison is generated.

Abstract: A method for inspecting assembly of components in a structure includes acquiring a visual representation of at least a portion of the structure, and saving an electronic file of the visual representation on a computer readable medium. A three-dimensional design of the structure, which contains information on a proper position of the components within the structure, is accessed. The visual representation is compared with the three-dimensional design using a computer, and a feedback indicating a result of the comparison is generated.