Turbine engine having a variable engine intake system
A turbine engine including a fan having a plurality of fan blades, a nacelle that extends circumferentially about the fan, an engine intake including an engine inlet, and a variable engine intake system. The nacelle includes a fan cowl and an inlet cowl that is movable with respect to the fan cowl. The engine inlet is defined from a leading edge of the nacelle to the plurality of fan blades. The variable engine intake system adjusts the inlet cowl axially between a fully retracted position and a fully extended position to adjust an inlet length of the engine inlet. The inlet cowl maintains contact with the fan cowl when the inlet cowl is extended.
1. A turbine engine comprising:
a fan having a plurality of fan blades;
a nacelle that extends circumferentially about the fan, the nacelle including a fan cowl and an inlet cowl that is movable with respect to the fan cowl;
an engine intake including an engine inlet defined from a leading edge of the nacelle to the plurality of fan blades; and
a variable engine intake system that adjusts the inlet cowl axially between a fully retracted position and a fully extended position to adjust an inlet length of the engine inlet, wherein the inlet cowl maintains contact with a radially outermost surface and a radially innermost surface of the fan cowl when the inlet cowl is extended.
2. The turbine engine of claim 1 , wherein the turbine engine includes a heating system disposed through the inlet cowl that heats the inlet cowl.
3. The turbine engine of claim 1 , wherein the variable engine intake system includes one or more actuators and a controller that controls the one or more actuators to adjust the inlet cowl.
4. The turbine engine of claim 1 , wherein the variable engine intake system adjusts the inlet cowl based on wind conditions about the turbine engine including at least one of crosswind conditions or wind shear conditions.
5. The turbine engine of claim 1 , wherein the variable engine intake system includes one or more actuators that each includes a rod that is coupled to the inlet cowl, and the one or more actuators extend and retract the rod to adjust the inlet cowl.
6. The turbine engine of claim 1 , wherein the variable engine intake system includes one or more actuators that each includes a pin disposed within one or more helical tracks, and the one or more actuators move at least one of the pins of the one or more actuators along the one or more helical tracks or the inlet cowl about the pin to adjust the inlet cowl axially between the fully retracted position and the fully retracted position.
7. The turbine engine of claim 1 , wherein the inlet length is defined axially from a leading edge of the plurality of fan blades at a fan hub of the fan to a leading edge of the nacelle, the engine inlet having an inlet diameter defined as a diameter of the fan at a tip of the plurality of fan blades, and a ratio of the inlet length to the inlet diameter is in a range of 0.2 to 1.0.
8. The turbine engine of claim 7 , wherein the inlet length includes a maximum inlet length in the fully extended position and a minimum inlet length in the fully retracted position, and a ratio of the maximum inlet length to the minimum inlet length is in a range of 1.1 to 2.0.
9. The turbine engine of claim 1 , wherein the inlet cowl includes one or more extension portions that extend aftward from the inlet cowl and over the fan cowl.
10. The turbine engine of claim 9 , wherein the one or more extension portions are tapered from the inlet cowl to the fan cowl such that there is a smooth transition from the one or more extension portions to the fan cowl.