METHOD AND DEVICE FOR SUPPRESSING THE FORMATION OF ICE ON STRUCTURES AT THE AIR INTAKE OF A TURBOMACHINE

• US 20140366552A1
• Filed: 06/17/2014
• Published: 12/18/2014
• Est. Priority Date: 06/18/2013
• Status: Active Grant

• Current Assignee: Ansaldo Energia Switzerland AG
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: SZWEDOWICZ, Jaroslaw Leszek, NEUBAUER, Marcus, SCHWARZENDAHL, Sebastian Marc, BAUER, Andreas
• Granted Patent: US 9,708,929 B2
• Time in Patent Office: Days
• US Class Current: 60/779
• CPC Class Codes: F01D 25/02 De-icing means for engines having icing phenomena
• CPC Class Codes: F02C 7/047 Heating to prevent icing
• CPC Class Codes: F03G 7/08 recovering energy derived from swinging, rolling, pitching or like movements, e.g. from the vibrations of a machine
• CPC Class Codes: F05D 2260/407 through piezoelectric conversion
• CPC Class Codes: F25C 5/08 by heating bodies in contact with the ice

Abstract

The application relates to a method and a device for suppressing ice formation on intake structures of a compressor, particularly the compressor of a gas turbine. The technical aim of the present invention is to provide a method and a device for suppressing the formation of ice on said structures, which avoid the disadvantages of known solutions, such as a reduction of the performance of the gas turbine, and have a simple and broad applicability. According to the present invention the mechanical vibratory energy of said structures during operation is converted into electrical energy by a piezoelectric element, firmly applied to said structure, and in a connected electrical circuit the generated electrical energy is then converted into thermal energy by an ohmic resistor and this thermal energy is conducted to at least a portion of the structure for suppressing ice formation. Excess energy may be transmitted by a transmitter to other circuits in adjacent structures.

Claims

1. Method for suppressing ice formation on the surface of a turbomachine structure, particularly an intake structure of a compressor, during its operation, the method comprising at least the steps of piezoelectrically converting mechanical vibratory energy of said structure into electrical energy, converting the generated electrical energy into thermal energy and conducting this thermal energy to at least a portion of the structure.

2. Method according to claim 1, comprising firmly applying at least one piezoelectric element to said structure and connecting the piezoelectric element to an electrical circuit, containing an ohmic resistor.

3. Method according to claim 1, wherein mechanical vibrations of the structure result in deforming the piezoelectric element, thus converting mechanical vibratory energy of the structure into an electrical voltage, initiating an electrical current in the connected electrical circuit, converting the electrical current into thermal energy in the ohmic resistor and conducting this thermal energy to at least a portion of the structure.

4. Method according to claim 2, wherein the electrical circuit additionally comprises a transmitter.

5. Method according to claim 4, wherein the electric circuit of a first structure at least comprises a piezoelectric element, a resistor and a transmitter and wherein an electric circuit of a second structure at least comprises a receiver and a resistor, and wherein the transmitter of circuit and the receiver of circuit are designed to transmit power by contactless energy transfer.

6. Method according to claim 5, wherein the first structure is a rotating blade and the second structure is an inlet guide vane and/or a stator part of the bellmouth.

7. Method according to claim 4, wherein the transmitter of the electrical circuit is designed to send a signal to a receiver of an external energy delivery system.

8. Method according to claim 7, wherein the external energy delivery device comprises at least the receiver, an electrical power source and a transmitter for contactless energy transfer.

9. Method according to claim 8, wherein the transmitter of the external energy delivery system transmits power by contactless energy transfer to at least one receiver of the electrical circuits that are applied to the structures, and the received signals are converted into heat by the resistors.

10. Method according to claim 9, wherein the external energy delivery device transmits power to all electrical circuits, applied to the structures.

11. Method according to claim 1, wherein the transmission of energy within the electrical circuits is at least partly based on a wireless technique.

12. Method according to claim 1, wherein more than one piezoelectric elements are applied to one structure and wherein said more than one piezoelectric elements are adjusted to one or more resonance frequencies.

13. Method according to claim 12, wherein the turbomachine is a compressor of a stationary gas turbine plant for power generation.

14. Device for conducting the method according to claim 1, at least comprising a casing with an inlet section consisting of a bellmouth, a rotor surrounded by the casing, a row of inlet guide vanes, connected to the casing and a row of rotating blades, connected to the rotor, wherein the bellmouth and/or at least one inlet guide vane and/or at least one rotating blade is equipped with a piezoelectric element and an electrical circuit, connected to this piezoelectric element.

15. Device according to claim 14, wherein the electrical circuit includes at least an ohmic resistor.

16. Device according to claim 14, wherein the electrical circuit contains at least a transmitter.

17. Device according to claim 16, wherein the electrical circuit, including the piezoelectric element, the ohmic resistor and the transmitter, is firmly applied to at least one rotating blade and/or to at least one inlet guide vane and/or to the casing and/or a strut of the bellmouth.

18. Device according to claim 17, wherein the electrical circuit, comprising the piezoelectric element, the ohmic resistor and the transmitter is applied to at least one rotating blade, and wherein an electrical circuit, comprising an ohmic resistor and an receiver is applied to at least one inlet guide vane and/or to the casing and/or to a strut of the bellmouth, and wherein the transmitter of the electrical circuit and the receiver of electrical circuit are designed to transmit power by contactless energy transfer.

19. Device according to claim 17, wherein an electrical circuit, comprising the piezoelectric element, the ohmic resistor and the transmitter is applied to at least one rotating blade, and wherein transmitter is designed to send a signal to a receiver of an external energy delivery system.

20. Device according to claim 19, wherein the external energy delivery system at least comprises the receiver, an electrical power source and a transmitter for contactless energy transfer to the receivers of the electrical circuits.

21. Device according to claim 20, wherein at least one of the rotating blades and/or the inlet guide vanes and/or the casing and/or the struts of the bellmouth are equipped with an electrical circuit, including a receiver and a resistor.

22. Device according to claim 14, wherein the piezoelectric element and the electrical circuit, connected to this piezoelectric element, are designed as a module and at least one such module is applied to one of the structures.

23. Device according to claim 22, wherein the module additionally comprises an ohmic resistor and/or a transmitter.

24. Device according to claim 22, wherein the electrical circuit, at least comprising a resistor and a receiver is designed as a module and at least one such module is applied to one of the structures.

25. Device according to claim 14, wherein the electrical circuits or the respective modules, including these circuits are applied to an outer surface or an inner surface of the structures or they are embedded in a wall of these structures.