Abstract:
One embodiment of the present is may include a gas turbine engine having an electrical machine for generating electrical power. Other embodiments may include other gas turbine engines having electrical machines for generating electrical power. Still other embodiments may include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines having electrical machines for generating electrical power.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 61/771,891 filed Mar. 3, 2013, the contents of which are hereby incorporated in their entirety. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to gas turbine engines, and more particularly, to gas turbine engines equipped with electrical machines for generating electrical power. 
     BACKGROUND 
     Gas turbine engines with generator or alternator systems remain an area of interest. Some existing systems have various shortcomings, drawbacks, and disadvantages relative to certain applications. Accordingly, there remains a need for further contributions in this area of technology. 
     SUMMARY 
     One embodiment of the present disclosure is a unique gas turbine engine having an electrical machine for generating electrical power. Other embodiments include other unique gas turbine engines having electrical machines for generating electrical power. Still other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines having electrical machines for generating electrical power. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein: 
         FIG. 1  schematically illustrates some aspects of a non-limiting example of a gas turbine engine in accordance with an embodiment of the present disclosure. 
         FIG. 2  schematically illustrates some aspects of a non-limiting example of an electrical machine for generating electrical power in accordance with an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     For purposes of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nonetheless be understood that no limitation of the scope of the disclosure is intended by the illustration and description of certain embodiments of the disclosure. In addition, any alterations and/or modifications of the illustrated and/or described embodiment(s) are contemplated as being within the scope of the present disclosure. Further, any other applications of the principles of the disclosure, as illustrated and/or described herein, as would normally occur to one skilled in the art to which the disclosure pertains, are contemplated as being within the scope of the present disclosure. 
     Referring to the drawings, and in particular  FIG. 1 , a non-limiting example of some aspects of a gas turbine engine  10  in accordance with an embodiment of the present disclosure is schematically depicted. In one form, gas turbine engine  10  is an aircraft propulsion power plant. In other embodiments, gas turbine engine  10  may be a land-based or marine engine. In one form, gas turbine engine  10  is a multi-spool turbofan engine. In other embodiments, gas turbine engine  10  may take other forms, and may be, for example, a turboshaft engine, a turbojet engine, a turboprop engine, or a combined cycle engine having a single spool or multiple spools. 
     As a turbofan engine, gas turbine engine  10  includes a fan system  12 , a bypass duct  14 , a compressor  16 , a diffuser  18 , a combustor  20 , a turbine  22 , an electrical machine  24 , a discharge duct  26  and a nozzle system  28 . Bypass duct  14  and compressor  16  are in fluid communication with fan system  12 . Diffuser  18  is in fluid communication with compressor  16 . Combustor  20  is fluidly disposed between compressor  16  and turbine  22 . In one form, combustor  20  includes a combustion liner (not shown) that contains a continuous combustion process. In other embodiments, combustor  20  may take other forms, and may be, for example and without limitation, a wave rotor combustion system, a rotary valve combustion system or a slinger combustion system, and may employ deflagration and/or detonation combustion processes. 
     Fan system  12  includes a fan rotor system  30 . In various embodiments, fan rotor system  30  includes one or more rotors (not shown) that are powered by turbine  22 . In the depicted embodiments, fan rotor system  30  is a cold section rotating stage in the form of a single rotating fan blade stage having a wheel  32  and a plurality of fan blades  34  that are circumferentially surrounded by a fan shroud  36 . In one form shroud  36  is configured to retain one or more blades  34  within engine  10  during a blade-off event. In other embodiments, shroud  36  may not be so configured. 
     Bypass duct  14  is operative to transmit a bypass flow generated by fan system  12  to nozzle  28 . Compressor  16  includes a compressor rotor system  38 , which are also referred to as cold section stages. In various embodiments, compressor rotor system  38  includes one or more rotors (not shown) that are powered by turbine  22 . Each compressor rotor includes a plurality of rows of compressor blades (not shown) that are alternatingly interspersed with rows of compressor vanes (not shown). The compressor blades are circumferentially surrounded by shrouds, e.g., in the form of blade tracks mounted on or formed as part of one or more compressor cases (not shown). Turbine  22  includes a turbine rotor system  40 . In various embodiments, turbine rotor system  40  includes one or more rotors (not shown) operative to drive fan rotor system  30  and compressor rotor system  38 . Each turbine rotor includes a plurality of turbine blades (not shown) that are alternatingly interspersed with rows of turbine vanes (not shown). The turbine blades are circumferentially surrounded by shrouds, e.g., in the form of blade tracks mounted on or formed as part of one or more compressor cases (not shown). 
     Electrical machine  24  is configured to generate electrical power. In one form, electrical machine  24  is disposed in (or adjacent to) fan system  12 . In other embodiments, electrical machine  24  may be disposed within (or adjacent to) compressor  16  or turbine  22 . In various embodiments, electrical machine  24  may be configured as a generator, an alternator or any other type of electrical machine that is configured to generate electrical power. 
     Turbine rotor system  40  is drivingly coupled to compressor rotor system  38  and fan rotor system  30  via a shafting system  42 . In various embodiments, shafting system  42  includes a plurality of shafts that may rotate at the same or different speeds and directions. In some embodiments, only a single shaft may be employed. Turbine  22  is operative to discharge an engine  10  core flow to nozzle  28 . In one form, fan rotor system  30 , compressor rotor system  38 , turbine rotor system  40  and shafting system  42  rotate about an engine centerline  46 . In other embodiments, all or parts of fan rotor system  30 , compressor rotor system  38 , turbine rotor system  40  and shafting system  42  may rotate about one or more other axes of rotation in addition to or in place of engine centerline  46 . 
     Discharge duct  26  extends between a discharge portion  48  of turbine  22  and engine nozzle  28 . Discharge duct  26  is operative to direct bypass flow and core flow from a bypass duct discharge portion  44  and turbine discharge portion  48 , respectively, into nozzle system  28 . In some embodiments, discharge duct  26  may be considered a part of nozzle  28 . Nozzle  28  is in fluid communication with fan system  12  and turbine  22 . Nozzle  28  is operative to receive the bypass flow from fan system  12  via bypass duct  14 , and to receive the core flow from turbine  22 , and to discharge both as an engine exhaust flow, e.g., a thrust-producing flow. In other embodiments, other nozzle arrangements may be employed, including separate nozzles for each of the core flow and the bypass flow. 
     During the operation of gas turbine engine  10 , air is drawn into the inlet of fan  12  and pressurized by fan  12 . Some of the air pressurized by fan  12  is directed into compressor  16  as core flow, and some of the pressurized air is directed into bypass duct  14  as bypass flow, and is discharged into nozzle  28  via discharge duct  26 . Compressor  16  further pressurizes the portion of the air received therein from fan  12 , which is then discharged into diffuser  18 . Diffuser  18  reduces the velocity of the pressurized air, and directs the diffused core airflow into combustor  20 . Fuel is mixed with the pressurized air in combustor  20 , which is then combusted. The hot gases exiting combustor  20  are directed into turbine  22 , which extracts energy in the form of mechanical shaft power sufficient to drive fan system  12  and compressor  16  via shafting system  42 . The core flow exiting turbine  22  is directed along an engine tail cone  50  and into discharge duct  26 , along with the bypass flow from bypass duct  14 . Discharge duct  26  is configured to receive the bypass flow and the core flow, and to discharge both as an engine exhaust flow, e.g., for providing thrust, such as for aircraft propulsion. 
     Referring to  FIG. 2 , some aspects of a non-limiting example of electrical machine  24  in accordance with an embodiment of the present disclosure is schematically illustrated. Electrical machine  24  includes a stator  60  and a rotor  62 , each of which includes electrical generating components. In one form, stator  60  and rotor  62  are disposed adjacent to fan blades  34 . In other embodiments, stator  60  and rotor  62  may be positioned adjacent to compressor blades and/or turbine blades in addition to or in place of fan blades  34 . 
     In one form, stator  60  is positioned adjacent to shroud  36 . In other embodiments, stator  60  may be positioned within shroud  36 , or may be disposed in another suitable location. Stator  60  includes as an electrical generating component an armature component  64 . In one form, armature component  64  is an armature winding. In various embodiments, armature component  64  may be in the form of a continuous ring extending circumferentially around rotor  62 , or may be formed of discreet armature elements, e.g., windings, spaced apart circumferentially around rotor  62 . In other embodiments, armature component  64  may take other forms. 
     Rotor  62  includes a hub  66 , a plurality of struts  68 , a plurality of rotor tips  70  and a plurality of electrical generating components in the form of field components  72 . In one form, rotor  62  is configured to rotate the same speed as fan rotor stage  30  during the operation of engine  10 . In other embodiments, rotor  62  may be configured to rotate at a different speed than fan rotor stage  30 . In one form, hub  66  is formed integrally with wheel  32  as an extension of wheel  32 . In other embodiments, hub  66  may be formed separately from wheel  32  and be coupled to wheel  32 . 
     Struts  68  extend radially outward from hub  66 , culminating at rotor tips  70 . Struts  68  are spaced apart circumferentially. Struts  68  are configured to support field components  72 . In one form, each strut  68  is configured to support and radially retain a single field component  72  during the operation of engine  10 . In other embodiments, each strut  68  may support and retain more than one field component  72 . In one form, each strut  68  is positioned adjacent to a blade  34 . In other embodiments, struts  68  may be positioned adjacent to a compressor blade and/or a turbine blade in addition to or in place of blade  34 . In one form, struts  68  are configured to rotate with blades  34 , e.g., such that the position of each strut  68  relative to an adjacent blade  34  is maintained during the operation of engine  10 . In one form, struts  68  are positioned downstream of blades  34 , which in some embodiments may reduce or eliminate aerodynamic losses associated with struts  68 . 
     Rotor tips  70  are positioned proximate to stator  60  in an axial position different from that of blades  34 . In one form, rotor tips  70  are positioned downstream of fan blades  34 . In other embodiments, rotor tips  70  may be positioned upstream of fan blades  34 . Field components  72  are disposed adjacent to stator  60 . In one form, field components  72  are in the form of magnets. In other embodiments, field components  72  may take other forms. In a particular form, field components  72  are in the form of permanent magnets. In other embodiments, other types of magnets may be employed as field components  72  in addition to or in place of permanent magnets, for example and without limitation, electromagnets. 
     Rotor  62  and stator  60  are configured to form a gap  74  therebetween, in particular, between field component  72  and armature component  64 . In one form, electrical machine  24  is cooled by the airflow pressurized by fan rotor stage  30  that passes through gap  74 . In other embodiments, electrical machine  24  may be cooled by other means in addition to or in place of the airflow pressurized by fan rotor stage  30  passing through gap  74 . 
     Embodiments of the present disclosure include a gas turbine engine, comprising: a cold section stage being at least one of a fan blade stage and a compressor blade stage, wherein the cold section stage includes plurality of blades and a shroud circumferentially surrounding the plurality of blades; a combustor in fluid communication with the at least one of the fan blade stage and the compressor blade stage; a turbine in fluid communication with the combustor; and an electrical machine configured to generate electrical power, wherein the electrical machine includes a stator and a rotor; wherein the stator is positioned adjacent to or within the shroud; and wherein the rotor includes a rotor tip positioned proximate to the stator and in a different axial location than the blades. 
     In a refinement, the stator includes an armature component positioned adjacent to or within the shroud; and wherein the rotor tip includes a field component positioned proximate to the stator. 
     In another refinement, the armature component is an armature winding; and wherein the field component is a magnet. 
     In yet another refinement, the rotor includes a hub and a strut extending from the hub, wherein the strut is configured to support the field component. 
     In still another refinement, the strut is positioned adjacent to a blade of the cold section stage. 
     In yet still another refinement, the strut is positioned downstream of the blade. 
     In a further refinement, the strut is configured to rotate with the blade. 
     In a yet further refinement, the cold section stage includes a wheel; wherein the rotor includes a hub and a strut extending from the hub; wherein the strut is configured to support the field component; and wherein the hub is coupled to the wheel or is formed as an extension of the wheel. 
     In a still further refinement, the rotor is configured to operate at the same rotational speed as the cold section stage during operation of the gas turbine engine. 
     In a yet still further refinement, the electrical machine is cooled by airflow pressurized by the cold section stage. 
     In an additional refinement, the rotor and the stator are configured to form a gap between the rotor and stator; and wherein the electrical machine is cooled by the airflow passing through the gap. 
     Embodiments of the present disclosure include a gas turbine engine, comprising: at least one of a rotating fan stage and a rotating compressor stage; a combustor in fluid communication with the at least one of the rotating fan stage and the rotating compressor stage; at least one rotating turbine stage in fluid communication with the combustor; and an electrical machine configured to generate electrical power, wherein the electrical machine includes a stator and a rotor; wherein the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage include a shroud circumferentially surrounding a plurality of blades of the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage; and wherein the stator is positioned adjacent to or within the shroud; and wherein the rotor includes a rotor tip positioned proximate to the stator and in a different axial location than the blades. 
     In a refinement, the stator includes an armature component positioned adjacent to or within the shroud; and wherein the rotor tip includes a field component positioned proximate to the stator. 
     In another refinement, the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage include includes a wheel; wherein the rotor includes a hub and a strut extending from the hub; wherein the strut is configured as part of the rotor; and wherein the hub is coupled to the wheel or is formed as an extension of the wheel. 
     In yet another refinement, the rotor is configured to operate at the same rotational speed as the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage during operation of the gas turbine engine. 
     In still another refinement, the rotor includes a hub and a strut extending from the hub. 
     In yet still another refinement, the strut is positioned adjacent to a blade of the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage. 
     In a further refinement, the strut is configured to rotate with the blade. 
     Embodiments of the present disclosure include a gas turbine engine, comprising: at least one of a rotating fan stage and a rotating compressor stage; a combustor in fluid communication with the at least one of the rotating fan stage and the rotating compressor stage; at least one rotating turbine stage in fluid communication with the combustor; and means for generating electrical power disposed adjacent to the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage. 
     In a refinement, the means for generating electrical power includes a stator, a rotor having struts and first electrical generating components disposed at tips of the struts; wherein the struts are positioned adjacent to and configured to rotate with the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage; wherein the at least one of the rotating fan stage and the rotating compressor stage and/or the at least one rotating turbine stage include a shroud; wherein the stator includes second electrical generating components positioned adjacent to or within the shroud. 
     While the disclosure has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the disclosure is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the disclosure, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary.