Aeronautics and astronautics – Aircraft sustentation – Sustaining airfoils
Patent
1998-02-27
2000-02-22
Poon, Peter M.
Aeronautics and astronautics
Aircraft sustentation
Sustaining airfoils
244130, 244204, 244 53B, B64C 2100
Patent
active
060270780
ABSTRACT:
A method and apparatus using localized heating to encourage laminar flow along an airfoil exterior surface. The airfoil includes a leading edge (24), a controlled surface (18), and an uncontrolled surface (20). The present invention localized heating system (38) includes a heat source (40) located within the airfoil and connected to the leading edge (24), and a heat sink (42) positioned aft of the heat source (40) and arranged to transfer heat from the airfoil controlled surface (18) to the uncontrolled surface (20). The heat sink (42) preferably expels heat along uncontrolled surface adjacent to turbulent air flow. In one preferred embodiment as applied to a generally circular aircraft engine nacelle (12), the heat source (40) is an electro-thermal heat source (44) having a high resistance wire embedded in a composite material leading edge structure (50), and the heat sink (42) is a heat pipe (52) having a wicking material (58) and a vaporizing agent (60). A method of encouraging laminar flow about a controlled surface of an airfoil is further provided. The method includes heating (61) the outer surface near the leading edge region, drawing (62) heat from a controlled surface downstream of the heated surface, and expelling (63) heat along the an uncontrolled surface.
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Crouch Jeffrey D.
Ng Lian L.
Dinh Tien
Poon Peter M.
The Boeing Company
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