Abstract:
One embodiment according to the present invention is a unique system for harnessing thermal energy of a gas turbine engine. Other embodiments include unique apparatuses, systems, devices, and methods relating to gas turbine engines. Further embodiments, forms, objects, features, advantages, aspects, and benefits of the present invention shall become apparent from the following description and drawings.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit of U.S. Provisional Patent Application No. 61/204,059, filed Dec. 31, 2008, and is incorporated herein by reference. 
     
    
     GOVERNMENT RIGHTS 
       [0002]    The present application was made with the United States government support under Contract No. N88858, awarded by the United States Navy. The United States government has certain rights in the present application. 
     
    
     FIELD OF THE INVENTION 
       [0003]    The present invention relates generally to gas turbine engines and more particularly to systems, apparatuses, and methods of harnessing thermal energy of gas turbine engine(s). 
       BACKGROUND 
       [0004]    Gas turbine engines are an efficient source of energy and have proven useful to propel aircraft and other flying machines, for electricity generation, as well as for other uses. One aspect of gas turbine engines is that they produce significant amounts of thermal energy during operation. It is well understood that some thermal energy is harnessed by a gas turbine engine during its operation; however, a significant amount of thermal energy is not harnessed or put to use and is lost. Thus, there remains a need for systems, apparatuses, and methods of harnessing thermal energy of gas turbine engine(s). 
       SUMMARY 
       [0005]    One embodiment according to the present invention is a unique system for harnessing thermal energy of a gas turbine engine. Other embodiments include unique apparatuses, systems, devices, and methods relating to gas turbine engines. Further embodiments, forms, objects, features, advantages, aspects, and benefits of the present invention shall become apparent from the following description and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is an illustrative view of an aircraft propelled by two gas turbine engines. 
           [0007]      FIG. 2  is a schematic representation of a gas turbine engine. 
           [0008]      FIG. 3  is a system schematic according to one embodiment of the present invention. 
           [0009]      FIG. 4  is a schematic timeline of an apparatus in several states according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    For purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
         [0011]    With reference to  FIG. 1 , there is shown airplane  100  including gas turbine engine engines  110  and  120  which operate to propel airplane  100 . Airplane  100  is one example of a use to which gas turbine engines can be put. There are a variety of additional applications for gas turbine engines, including, for example, electricity generation, pumping sets for gas and oil transmission lines, land and naval propulsion, and still other applications. It should be appreciated that systems, apparatuses, and methods according to the present invention can be used in connection with the gamut of gas turbine engine applications. Thus, while the following description is in the context of one embodiment of a gas turbine engine suitable for aircraft propulsion, the invention broadly applies to the aforementioned applications and others. 
         [0012]    With reference to  FIG. 2 , there is illustrated a schematic view of a gas turbine engine  200  which includes a compression system  215 , a combustor section  223 , and a turbine section  224  that are integrated together to produce an aircraft flight propulsion engine. In one form, the compression system  215  includes a fan section  221  and a compressor section  222 . This type of gas turbine engine is generally referred to as a turbo-fan. One alternate form of a gas turbine engine includes a compressor, a combustor, and a turbine that have been integrated together to produce an aircraft flight propulsion engine without-the fan section. The term aircraft broadly includes helicopters, airplanes, missiles, unmanned space devices and any other substantially similar devices. It is important to appreciate that there are a multitude of ways in which the gas turbine engine components can be linked together. For example, additional compressors and turbines could be added with intercoolers connecting between the compressors and reheat combustion chambers could be added between the turbines. A wide variety of additional configurations and variations are also possible. 
         [0013]    The compressor section  222  includes a rotor  219  having a plurality of compressor blades  228  coupled thereto. The rotor  219  is affixed to a shaft  225  that is rotatable within the gas turbine engine  220 . A plurality of compressor vanes  229  are positioned within the compressor section  222  to direct the fluid flow relative to blades  228 . Turbine section  224  includes a plurality of turbine blades  230  that are coupled to a rotor disk  231 . The rotor disk  231  is affixed to the shaft  225 , which is rotatable within the gas turbine engine  220 . Energy extracted in the turbine section  224  from the hot gas exiting the combustor section  223  is transmitted through shaft  225  to drive the compressor section  222 . Further, a plurality of turbine vanes  232  are positioned within the turbine section  224  to direct the hot gaseous flow stream exiting the combustor section  223 . 
         [0014]    The turbine section  224  provides power to a fan shaft  226 , which drives the fan section  221 . The fan section  221  includes a fan  218  having a plurality of fan blades  233 . Air enters the gas turbine engine  220  in the direction of arrows A and passes through the fan section  221  into the compressor section  222  and a bypass duct  227 . The term airfoil will be utilized herein to refer to fan blades, fan vanes, compressor blades, turbine blades, compressor vanes, and turbine vanes unless specifically stated otherwise. Further details related to the principles and components of a conventional gas turbine engine will not be described herein as they are known to one of ordinary skill in the art. 
         [0015]    With reference to  FIG. 3  there is shown a system  300  according to one embodiment of the present invention. System  300  includes a gas turbine engine  310  which includes a housing  312 . A chamber  314  is coupled to housing  312  and contains water  316 . In an operational state, engine  310  rapidly becomes hot (for example up to 3000° C. or more) as indicates by letter H. In a non operational state engine  310  can be at room temperature, or at other non-operational temperatures as indicated by letters RT. At room temperature water  316  is in a substantially liquid physical phase; however, at an operational temperature, water  316  will undergo a phase change to become super heated steam. Given the high operating temperature of engine  310  this phase change can occur very rapidly, and can be nearly instantaneous upon engine operation. In certain applications, such as aircraft, additional heat can be generated on or about housing  314  through air drag. Such heat resulting from engine operation can be harnessed according to various embodiments of the present invention. 
         [0016]    It should be appreciated that the illustrated coupling of engine  310  and chamber  314  where housing  312  and chamber  314  share a common wall is only one exemplary configuration. A number of other embodiments are contemplated, for example, coupling where the chamber is separated from the housing by one or more additional walls or other structures, or a portion of the chamber or some intermediate heat transfer structure extends into or through housing  312 . Regardless of the particular configuration, system  300  includes thermal coupling of engine  310  and water  316  effective to promote or cause a phase change of water  316 . Thermal coupling can include conduction, convention, radiation, or combination of these and other modes of heat transfer. It should also be appreciated that a variety of materials having the capacity to change phases within the operational/non-operational range of engine  310  could be used instead of or in addition to water. For example, materials such as other motive fluids for gas turbine engines or combinations of these or other materials could also be used. There may also be provided one or more devices to introduce additional water to chamber  314 . 
         [0017]    Chamber  314  is coupled to valve  320  by conduit  318 . Though not illustrated, an additional valve, such as a steam valve or one way flow valve, can optionally be provided between chamber  314  and valve  320  to control movement of matter from chamber  314  to or at some position along conduit  318 . Several such additional valves and other intermediate parts or pathways could also be included. Once water  316  changes phase to steam, assuming no barrier exists, it travels to or pressurizes a flow passage within conduit  318  as indicated by arrow S 1 . Steam then travels through conduit  318  and ultimately encounters valve  320  as indicated by arrow S 2 . Valve  320  can be closed, open to the right so that steam travels to conduit  322  in the direction indicated by arrow S 3 , open to the left so that steam travels to conduit  324  in the direction indicated by arrow S 4 , partially open in either or both directions, or open to provide external venting such as in the case of an emergency vent. 
         [0018]    Conduits  322  and  324  are coupled to actuator  330 . Conduit  322  leads to chamber  333  as illustrated by arrow S 5 . Conduit  324  leads to chamber  332  as illustrated by arrow S 6 . Thus, depending upon the setting of valve  320 , the relative pressure of chambers  332  and  333  can be varied. Such variation can cause movement of piston  331  which in turn can move rod  333  and ultimately act upon load  350 . As arrow M-M shows, this motion can be reciprocation. A variety or other movement can also occur, for example, rotation, vibration, twisting, torque, orbital motion, bending, and virtually any other manner of movement, force or action. It should also be appreciated that a variety of other actuators could be used to accomplish a variety of other purposes. For example, the actuator could include or could be coupled to a variable geometry actuator, such as a piston, operable to drive the variable geometry of a compressor. The actuator could include or could be coupled to an injector for direct injection into one or more locations in a gas turbine engine which could result in a variety of pollution and performance improvements. Furthermore, the actuator could include or could be coupled to an electrical generator such as a small steam turbine or other generation device. Additionally, the actuator could include or could be coupled to an injector for injection into the exhaust stream for IR or noise suppression purposes. Thus it will be understood that actuators according to various embodiments of the present invention include the foregoing and other devices operable to move, apply force, transfer matter such as steam or other motive fluid, and/or do some work. 
         [0019]    With reference to  FIG. 4  there is shown a timeline  400  illustrating an apparatus  410  in several states  410 A,  410 B,  410 C,  410 D,  410 E, and  410 F. Each state corresponds to a time along timeline T O -T N , specifically, state  410 A is at or about time T O , state  410 B is at or about time T 1 , state  410 C is at or about time T 2 , state  410 D is at or about time T 3 , state  410 E is at or about time T 4 , and state  410 F is at or about time T 5 . The several states of apparatus  410  each include a gas turbine engine including a housing  412  which is coupled to a chamber  414  which contains a liquid or other phase excitable material. A flow path  418  can interconnect chamber  414  and actuator  430 . There is also provided a triggerable pressure inducement element  490  which could be, for example, an explosive, a combustible, a valve opening to a pressure source such as a tank of flow passage, a cartridge, a compressor, an injector or any other source of pressure or combination of sources. For convenience element  490  is illustrated as an explosive; however, the foregoing and other alternatives are also contemplated. 
         [0020]    Along the timeline T O -T N  apparatus  410  begins at T O  in a room temperature or other non-operational state. Water or other matter  416  is in a liquid phase. Explosive  490  is un-exploded, but triggerable by a variety of techniques. Then at T 1  explosive  490  is triggered. At T 2  explosive force begins traveling along pathway  418  as shown by the arrows. At T 3  the explosive force reaches actuator  430 . At T 4  (which could be simultaneous or subsequent to T 3 ) actuator  430  is actuated. Also at (or before or subsequent to) T 4 , the engine is started and moves from non-operational temperature to a hot operating state. Through transfer across a heat transfer interface, such as the illustrated intermediate metal wall structure, but optionally any of a wide variety of heat transfer structures including sinks, conductors, piping, counter flow, and/or combinations of these ant other interfaces, a phase change or excitement in matter  416  occurs. At T 5  the phase change or excitement reaches and actuates actuator  430 . 
         [0021]    While the invention 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 invention is not to be limited to the disclosed embodiment(s), but rather, 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 invention, 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.