Systems and methods for fan blade de-icing
An anti-ice arrangement for a gas turbine engine may comprise an engine static structure, a fan blade housed for rotation within the engine static structure, and a magnetic field source mounted in close proximity to the fan blade and configured for inducing eddy currents in the fan blade to increase a surface temperature of the fan blade.
1. An anti-ice arrangement for a gas turbine engine, comprising:
an engine static structure;
a fan blade housed for rotation within the engine static structure;
a magnetic field source mounted in close proximity to the fan blade and configured for inducing eddy currents in the fan blade to increase a surface temperature of the fan blade; and
a tailored resistance coating disposed on the fan blade, wherein the resistance coating is configured to at least one of increase or decrease heat generated by the eddy currents through the tailored resistance coating.
2. The anti-ice arrangement of claim 1 , wherein rotation of the fan blade about an engine central longitudinal axis relative to the magnetic field source induces the eddy currents.
3. The anti-ice arrangement of claim 2 , wherein the magnetic field source is disposed at least one of radially outward from a tip of the fan blade, radially inward from a root of the fan blade, or aft of the fan blade.
4. The anti-ice arrangement of claim 3 , further comprising a splitter dividing a core flow path and a bypass flow path, wherein the magnetic field source is mounted in the splitter.
5. The anti-ice arrangement of claim 1 , wherein the magnetic field source is a permanent magnet having a continuously induced magnetic field.
6. The anti-ice arrangement of claim 1 , wherein the tailored resistance coating is disposed on at least one of a leading edge of the fan blade, a suction side of the fan blade, and a pressure side of the fan blade.
7. The anti-ice arrangement of claim 1 , wherein the magnetic field source is an electromagnet, the anti-ice arrangement further comprising:
a power electronics in electronic communication with the electromagnet; and
a controller in electronic communication with the power electronics, wherein the controller selectively commands an electric power supplied to the electromagnet via the power electronics in response to an input received by the controller.
8. The anti-ice arrangement of claim 7 , wherein the input corresponds to at least one of:
an ambient air temperature;
an ambient air humidity;
a fan blade speed; or
a vibration.
9. The anti-ice arrangement of claim 8 , wherein the controller commands the electric power supplied to the electromagnet in response to determining whether icing conditions are favorable based upon a calculated unheated fan blade surface temperature.
10. The anti-ice arrangement of claim 9 , wherein the controller commands the electric power supplied to the electromagnet in response to detecting an imbalance generated by asymmetric ice shedding from the fan blade via the vibration.
11. The anti-ice arrangement of claim 1 , further comprising a second magnetic field source mounted in close proximity to the fan blade and configured for inducing eddy currents in the fan blade to increase the surface temperature of the fan blade;
wherein the magnetic field source is a passive magnet; and
the second magnetic field source is an electromagnet.
12. The anti-ice arrangement of claim 1 , further comprising a second tailored resistance coating disposed on the fan blade,
wherein the tailored resistance coating is configured to increase heat generated by the eddy currents through the tailored resistance coating, and
the second resistance coating is configured to decrease heat generated by the eddy currents through the tailored resistance coating.
13. A method for anti-ice control, comprising:
sensing, by a controller, an ambient air temperature;
sensing, by the controller, an ambient air humidity;
estimating, by the controller, a forward aircraft speed;
estimating, by the controller, a fan blade speed;
calculating, by the controller, a fan blade surface temperature, wherein the fan blade surface temperature is calculated based upon at least one of:
i) a temperature sensor feedback signal; or
ii) the ambient air temperature, the ambient air humidity, the forward aircraft speed, and the fan blade speed;
determining, by the controller, if icing conditions are favorable based upon the fan blade surface temperature, wherein the favorability of the icing conditions corresponds to a likelihood of ice accretion on a fan blade; and
commanding, by the controller, power on to an electromagnet in response to the icing conditions being determined favorable.
14. The method of claim 13 , further comprising commanding, by the controller, power off to the electromagnet in response to the icing conditions being determined unfavorable.
15. The method of claim 13 , further comprising detecting, by the controller, a non-zero rotor speed.
16. The method of claim 13 , further comprising determining, by the controller, that an aircraft is flying through visible water comprising at least one of rain or cloud droplets.
17. The method of claim 13 , further comprising determining, by the controller, that the fan blade temperature is less than or equal to 0° C. (32° F.).
18. A method for anti-ice control for a gas turbine engine, comprising:
receiving, by a controller, a vibration sensor signal from a vibration sensor;
detecting, by the controller, an imbalance generated by asymmetric ice shedding from a fan blade via the vibration sensor signal; and
commanding, by the controller, power on to an electromagnet in response to the imbalance being detected;
wherein the vibration sensor is mounted to an engine static structure of the gas turbine engine, and the vibration sensor comprises an accelerometer.
19. The method of claim 18 , wherein the electromagnet is mounted in close proximity to the fan blade and configured for inducing eddy currents in the fan blade to increase a surface temperature of the fan blade in response to the power being commanded by the controller.