Patent Application
20190277197
The present disclosure relates generally to the field gas turbine power generation and specifically to control of electrical power output as applied to off-grid electric power generation.
Gas turbines are commonly configured with generators and used to provide off-grid power generation. There two general architectures: single shaft engines (
There remains a need for a free-power turbine engine with both excellent transient behavior under block-loading conditions as well as excellent part-load efficiency over a wide power range.
These and other needs are addressed by the present disclosure of a multi-spool gas turbine engine incorporating a free power turbine (for example, as illustrated in
A gas turbine configuration as disclosed herein exhibits exceptionally rapid transient response when presented with a rapid change in torque, such as a torque spike, characteristic of a rapid power increase from block loading. The following features are uniquely combined to provide the desired responsive behavior:
1. A free power turbine which characteristically provides increasing torque with decreasing speed (for example, as illustrated in
2. A turbine shaft-speed alternator. A turbine shaft-speed alternator is a high speed alternator and, as such, is typically a low mass device and therefor will have a very high power density. The high-speed alternator would typically be a permanent magnetic type, an induction type, or a switched reluctance type.
3. The disclosed variable area nozzle (“VAN”) upstream of the free power turbine may be configured to open rapidly. Upon experiencing a torque spike, a VAN may open rapidly. This response provides a rapid increase in air flow aspirated by the engine. Combining this with a proportional increased fuel supply enables the power of the free power turbine to increase with a characteristic time constant close to that of the fuel valve and VAN movement.
4. A fast acting fuel valve. The valve may deliver natural gas or liquid fuel to the engine. An alternative to the valve is a variable speed natural gas compressor. The motor of the compressor may be connected to a variable frequency drive (“VFD”). An electronic signal sent to this VFD device may provide fast acting fuel control.
5. A fast-acting actuator driving the variable area turbine nozzle (“VAN”).
6. A multistage turbo-machine, whereby dividing the work of compression and expansion into multiple spools serves to lower an overall moment of inertia of the machine. This moment of inertia is often referred to as ‘turbo-lag’ in the field of turbochargers. Dividing the work of compression and expansion into multiple spools in a gas turbine has a similar transient behavior benefit.
7. Further reductions in the ‘turbo-lag’ phenomenon are achieved when one or both turbines are fabricated from light-weight ceramic materials.
8. Coupling a variable speed alternator to the free power turbine and coupling the rectified alternator output to an inverter whose impedance can be varied serves to isolate the speed change of the alternator from the frequency delivered to the power grid (the aforementioned 50, 60 or 400 Hz). This enables the engine to achieve high efficiency at part-power. When an electrical load is applied, starting from any power level, the instantaneous power demand may, first be met by the low inertia in the high-speed power turbine-alternator assembly and, if needed, by an ultra-capacitor. During transient of (for example, 1 to 4 seconds), the aforementioned power turbine may dip in speed, but recover rapidly owing to the behavior previously described. Throughout such a transient, the inverter may continue to deliver precisely the ISO quality frequency (50 or 60 Hz). A ‘blip’ in power may be made-up by the ultra-capacitor. A large battery may alternatively be used in some embodiments, but may require a power rating equal to that of the engine's generator, with large associated energy capacity and high cost. Preferably, a much smaller ultra-capacitor with capacity to deliver full engine-rated power for a few seconds which may be less expensive. A power turbine's behavior may be such that it changes speed quickly, drooping slightly but rapidly recovering. The integrated energy (power multiplies by time) may be very small, compared to what a typical battery would provide. The small stored energy may be most economically supplied by the ultra-capacitor. While in some block-load (or step-loads) the speed droop may not exceed ISO standards, for example 3% for <3 seconds, in larger load steps, the electrical capacitance can be drawn-upon to make up the power deficit, enabling the inverter to uphold the frequency, without noticeable change. For clarity, any perturbation on the output frequency line may be corrected in one or two cycles. (for example, ˜ 1/60th of a second). Since the engine is able to deliver full power at sub-rated power turbine speed, the interruption in delivery of AC power to the grid is minimized; and
9. A small resistor bank, for example sized to provide the opposite feature of the aforementioned ultra-capacitor, may be used in instances when power (load) is dropped quickly. This resistor may be installed on the DC or AC link (
The combined benefits of these nine features create a unique engine architecture with exceptionally agile transient behavior in an environment characterized by volatile load shifts.
Furthermore, as compared to the contemporary single shaft engine (as illustrated in
The proposed engine with three degrees of control freedom achieves exceptional efficiency by asserting control over the turbine inlet temperature at part-load. Maintaining high turbine inlet temperature maximizes the Carnot efficiency. Control over the turbine inlet temperature, or so-called firing temperature, improves combustor stability at part-load, thereby reducing carbon monoxide emissions and avoiding fuel piloting which tends to increase NOx emissions.
A gas turbine engine in some embodiments comprises one or more turbo-compressor spools wherein each spool comprises a compressor, a turbine, and a first rotatable shaft rotatably coupling the compressor and the turbine. The gas turbine engine further comprises a combustor for receiving a high-pressure airflow from the compressors of each of the turbo-compressor spools and delivering a heated airflow to the turbines of each of the turbo-compressor spools. The gas turbine engine further comprises a free turbine spool comprising a free turbine and a second rotatable shaft, the second rotatable shaft rotatably coupling the free turbine to one of a variable speed alternator and a generator, wherein the one of the variable speed alternator and the generator generates for the purpose of generating electrical power. The electrical output of the variable speed alternator or generator is delivered to an active rectifier. The inverter accepts the electrical power from the active rectifier and converts the electrical power to utility-quality frequency at 50, 60 or 400 Hz. The gas turbine engine further comprises a recuperator and a variable area nozzle on the free power turbine. The gas turbine engine further comprises a fast-acting actuator controlling the variable area nozzle; an intercooler between the compressor of the first turbo-compressor spool of the one or more spools and the compressor of the second turbo-compressor spool of the one or more spools and one or more ultra-capacitors connected to a DC link between the active rectifier and the inverter, wherein the capacitors are operable to provide a pulse of DC power upon detection of a block loading event.
A method of operating a gas turbine engine is disclosed wherein the method comprises receiving, by a combustor of the gas turbine engine, a high-pressure air flow from a compressor of each of one or more turbo-compressor spools, wherein each spool of the one or more spools comprises a compressor, a turbine, and a first rotatable shaft rotatably coupling the compressor and the turbine; delivering a heated airflow to the turbine of each of the spools, wherein the airflow rotatably drives the first rotatable shaft and the compressor of each of the turbo-compressor spools; generating, by one of a variable speed alternator and a generator, electrical power, wherein the one of the variable speed alternator and the generator is rotatably coupled to a free turbine spool comprising a free turbine and a second rotatable shaft; accepting, by an inverter, the electrical power from an active rectifier; and converting, by the inverter, the electrical power to utility-quality frequency. The method of operating a gas turbine whereby the gas turbine engine further comprises a heat exchanger and a variable area nozzle with a fast-acting actuator on the free turbine. The method of operating a gas turbine engine whereby the gas turbine engine further comprises an intercooler between a compressor of a first turbo-compressor spool of the one or more spools and a compressor of a second turbo-compressor spool of the one or more spools. The method of operating a gas turbine engine providing, by one or more ultra-capacitors connected to a DC link between the active rectifier and the inverter, a pulse of DC power upon detection of a block loading event wherein the utility-quality frequency is one of 50, 60, and 400 Hz.
A system for overcoming effects of turbo lag on a block loaded gas turbine engine is disclosed, the system comprising a gas turbine engine having one or more turbo-compressor spools, wherein each turbo-compressor spool has a compressor, a turbine, and a first rotatable shaft rotatably coupling the compressor and the turbine. The gas turbine engine also has a combustor for receiving a high-pressure airflow from the compressor of each of the turbo-compressor spools and delivers a heated airflow to the turbine of each of the turbine-compressor spools, wherein the airflow rotatably drives the first rotatable shaft and the compressor of each of the turbine-compressor spools. The system further comprises a free turbine spool comprising a free turbine and a second rotatable shaft, the second rotatable shaft rotatably coupling the free turbine to one of a variable speed alternator and a generator, wherein the one of the variable speed alternator and the generator generates electrical power. The system further comprises an active rectifier; and an inverter accepting the electrical power from the active rectifier wherein the electrical power from the inverter is converted to utility-quality frequency. The system further comprises a recuperator and a variable area nozzle on the free turbine. The system may further comprise an intercooler between a compressor of a first spool of the one or more spools and a compressor of a second spool of the one or more spools. The system further comprises one or more ultra-capacitors connected to a DC link between the active rectifier and the inverter, wherein the capacitors provide a pulse of DC power upon detection of a block loading event and wherein the system maintains an output of utility-quality frequency that is one of 50, 60, and 400 Hz.
The above-described embodiments and configurations are neither complete nor exhaustive. As will be appreciated, other embodiments of the disclosure are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
The following definitions are used herein:
The phrases at least one, one or more, and and/or are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B and C together.
An alternator is an electrical generator that converts mechanical energy to electrical energy in the form of alternating current.
Block loading means suddenly increasing load to an electrical generator set. Block loading causes a sudden reduction of the engine speed with resulting fluctuating power output from the generator. Block loading occurs when an engine, such as a diesel engine, gas turbine engine or the like, is driving an electrical generator and the generator set experiences a sudden increase in load due to a planned requirement. Block loading usually occurs when an external electrical load is applied suddenly to the generator. The generator will attempt to provide for the increase in electrical power demand by drawing more mechanical power from the engine and converting the additional mechanical power to electrical power. As a result of the increase of mechanical load, the engine may reduce the rotational speed of the drive shaft as the resistance on the shaft increases. Until additional fuel and air can be directed into the engine, the engine compensates by producing a higher output of mechanical power required by the generator and tries to recover. That means that block loading causes a temporary increase of fuel consumption. If block loading occurs, it can cause the electrical power output of the generator to waver. This is important for the use of the generator set, because the variation in a frequency may affect the speed of, for example, an electrical motor that is needed in a process where it is very important to have constant speed on the shaft of the electric motor.
The Brayton cycle is a thermodynamic cycle that describes the workings of the gas turbine engine. It is named after George Brayton, the American engineer who developed it. It is also sometimes known as the Joule cycle. The ideal Brayton cycle consists of an isentropic compression process followed by an isobaric combustion process where fuel is burned, then an isentropic expansion process where the energized fluid gives up its energy to operate compressors or produce engine power and lastly an isobaric process where low grade heat is rejected to the atmosphere. An actual Brayton cycle consists of an adiabatic compression process followed by an isobaric combustion process where fuel is burned, then an adiabatic expansion process where the energized fluid gives up its energy to operate compressors or produce engine power and lastly an isobaric process where low grade heat is rejected to the atmosphere.
A ceramic is an inorganic, nonmetallic solid prepared by the action of heating and cooling. Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous (e.g., a glass).
Design point as used herein means the engine speed or power at which optimum fuel efficiency and/or thermodynamic efficiency is achieved.
The terms determine, calculate and compute and variations thereof are used interchangeably and include any type of methodology, process, mathematical operation or technique.
An engine is a prime mover and refers to any device that uses energy to develop mechanical power, such as motion in some other machine. Examples are diesel engines, gas turbine engines, microturbines, Stirling engines and spark ignition engines.
A free power turbine as used herein is a turbine which is driven by a gas flow and whose rotary power is the principal mechanical output power shaft. A free power turbine is not connected to a compressor in the gasifier section. A power turbine may also be connected to a generator or alternator. Typically the low speed generator operates at a speed synchronized to the utility (for example, 50 Hz, 60 Hz). This connection is generally made through a gearbox to allow the turbine and generator to operate at separate speeds. So-called high speed, or shaft-speed alternators operate at the turbine rotational speed. In this case, electronic conversion devices are required to synthesize utility grade power.
Fuel piloting means using a pilot fuel line to provide a rich diffusion flame which is always on and which enables the engine to keep functioning at low engine speeds. In a gas turbine engine, the main fuel supply is pre-mixed for low emissions.
A gas turbine engine as used herein may also be referred to as a turbine engine or microturbine engine. A microturbine is commonly a sub category under the class of prime movers called gas turbines and is typically a gas turbine with an output power in the approximate range of about a few kilowatts to about 700 kilowatts. A turbine or gas turbine engine is commonly used to describe engines with output power in the range above about 700 kilowatts. As can be appreciated, a gas turbine engine can be a microturbine since the engines may be similar in architecture but differing in output power level. The power level at which a microturbine becomes a turbine engine is arbitrary and the distinction has no meaning as used herein.
A gasifier is a turbine-driven compressor in a gas turbine engine dedicated to compressing air that, once heated, is expanded through a power turbine to produce energy.
In electrical generation, a generator is a device that converts mechanical energy into electrical power for use in an external circuit.
The grid or grid power as used herein is a term used for an electricity network which may support some or all of electricity generation, electric power transmission and electricity distribution. The grid may be used to refer to an entire continent's electrical network, a regional transmission network or may be used to describe a subnetwork such as a local utility's transmission grid or distribution grid. Generating plants may be large or small and may be located at various points around the grid. The electric power which is generated is stepped up to a higher voltage—at which it connects to the transmission network. The transmission network may move (wheel) the power long distances until it reaches a wholesale customer (for example the company that owns the local distribution network). Upon arrival at the substation, the power may be stepped down in voltage—from a transmission level voltage to a distribution level voltage. As the power exits the substation, it enters the distribution wiring. Finally, upon arrival at the service location, the power is stepped down again from the distribution voltage to the required service voltage(s). Existing national or regional grids simply provide the interconnection of facilities to utilize whatever redundancy is available. The exact stage of development at which the supply structure becomes a grid is arbitrary. Similarly, the term national grid is something of an anachronism in many parts of the world, as transmission cables now frequently cross national boundaries. Utilities are under pressure to evolve their classic topologies to accommodate distributed generation. As generation becomes more common from rooftop solar and wind generators, the differences between distribution and transmission grids will continue to blur.
An intercooler as used herein may comprise a heat exchanger positioned between the output of a compressor of a gas turbine engine and the input to a higher pressure compressor of a gas turbine engine. Air, or in some configurations, an air-fuel mix is introduced into a gas turbine engine and its pressure is increased by passing through at least one compressor. The working fluid of the gas turbine then passes through the hot side of the intercooler and heat is removed typically by an ambient fluid such as, for example, air or water flowing through the cold side of the intercooler.
The term means shall be given its broadest possible interpretation in accordance with 35 U.S.C., Section 112, Paragraph 6. Accordingly, a claim incorporating the term “means” shall cover all structures, materials, or acts set forth herein, and all of the equivalents thereof. Further, the structures, materials or acts and the equivalents thereof shall include all those described in the summary of the disclosure, brief description of the drawings, detailed description, abstract, and claims themselves.
A metallic material is a material containing a metal or a metallic compound. A metal refers commonly to alkali metals, alkaline-earth metals, radioactive and non-radioactive rare earth metals, transition metals, and other metals.
A prime power source refers to any device that uses energy to develop mechanical or electrical power, such as motion in some other machine. Examples are diesel engines, gas turbine engines, microturbines, Stirling engines, spark ignition engines and fuel cells.
Power density as used herein is power per unit volume (watts per cubic meter).
A recuperator is a heat exchanger dedicated to returning exhaust heat energy from a process back into the process to increase process efficiency. In a gas turbine thermodynamic cycle, heat energy is transferred from the turbine discharge to the combustor inlet gas stream, thereby reducing heating required by fuel to achieve a requisite firing temperature.
A single shaft gas turbine engine is comprised of a single shaft for its compressor, turbine and output alternator.
Specific power as used herein is power per unit mass (watts per kilogram).
Spool refers to a group of turbo-machinery components on a common shaft.
Spool speed as used herein means spool shaft rotational speed which is typically expressed in revolutions per minute (“rpms”). As used herein, spool rpms and spool speed may be used interchangeably.
A turbine is a rotary machine in which mechanical work is continuously extracted from a moving fluid by expanding the fluid from a higher pressure to a lower pressure. The simplest turbines have one moving part, a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades, or the blades react to the flow, so that they move and impart rotational energy to the rotor.
Turbine Inlet Temperature (TIT) as used herein refers to the gas temperature at the outlet of the combustor which is closely connected to the inlet of the high pressure turbine and these are generally taken to be the same temperature.
Turbocharger-like architecture or turbocharger technology means spools which are derived from modified stock turbocharger hardware components. In an engine where a centrifugal turbine with a ceramic rotor is used, the tip speed of the rotor is held to a proven allowable low limit (<500 m/s). Centrifugal compressors and radial inlet turbines are typically used in turbocharger applications.
A turbo-compressor spool assembly as used herein refers to an assembly typically comprised of an outer case, a centrifugal compressor, a radial inlet turbine wherein the centrifugal compressor and radial inlet turbine are attached to a common shaft. The assembly also includes inlet ducting for the compressor, a compressor rotor, a diffuser for the compressor outlet, a volute for incoming flow to the turbine, a turbine rotor and an outlet diffuser for the turbine. The shaft connecting the compressor and turbine includes a bearing system.
A two-shaft engine, also known as free-power turbine engine, as used herein comprises a turbine which is driven by a gas flow and whose rotary power is the principal mechanical output power shaft. A free power turbine is not connected to a compressor in the gasifier section, although the free power turbine may be in the gasifier section of the gas turbine engine.
An ultra-capacitor (also called a super capacitor) is a capacitor with capacitance value much higher than other capacitors, but usually with a lower voltage limit, that bridges the gap between electrolytic capacitors and rechargeable batteries. An ultra-capacitor typically stores 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and tolerate many more charge and discharge cycles than rechargeable batteries.
The present disclosure may take form in various components and arrangements of components, and in various steps and arrangements of steps. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the disclosure. In the drawings, like reference numerals refer to like or analogous components throughout the several views.
The single shaft gas turbine engines shown in
As shown in
In the gas turbine engine of
Gas is ingested via inlet 501 into a low pressure compressor 511. The outlet of the low pressure compressor 511 passes through an intercooler 512 which removes a portion of heat from the gas stream. The gas then enters a high pressure compressor 513. The outlet 503 of high pressure compressor 513 passes through the cold side of a recuperator 514 where a portion of heat from the exhaust gas is transferred to the gas flow from the high pressure compressor 513. The further heated gas 504 from the cold side of recuperator 514 is then directed to a combustor 515 where a fuel is burned, adding heat energy to the gas flow. The gas 505 emerging from the combustor 515 then enters a high pressure turbine 516 where work is done by turbine 516 to operate high pressure compressor 513. The gas 506 from the high pressure turbine 513 then drives low pressure turbine 517 where work is done by turbine 517 to operate low pressure compressor 511. The gas 507 exiting from low pressure turbine 517 then passes through variable area nozzle 524 and enters free power turbine 521. The shaft of free power turbine 512, in turn, drives a variable speed alternator 522. The variable speed alternator 522 delivers AC power to power electronics module 523 as further described in
The proposed configuration of
The gas turbine configuration of
1. The free power turbine which characteristically provides increasing torque with decreasing speed (
2. A turbine shaft-speed alternator. A turbine shaft-speed alternator is a high speed alternator and, as such, it is typically a low mass device and therefor will have a very high power density. The high-speed alternator would typically be a permanent magnetic type, an induction type, or a switched reluctance type.
3. The proposed variable area nozzle (“VAN”) upstream of the free power turbine is configured to open rapidly. Upon experiencing the torque spike, this VAN is opened rapidly. This provides a rapid an increase in air flow aspirated by the engine. Combining this with a proportional increased fuel supply enables the power of the free power turbine to increase with a characteristic time constant close to that of the fuel valve and VAN movement.
4. A fast acting fuel valve. The valve may deliver natural gas or liquid fuel to the engine. An alternative to the valve is a variable speed natural gas compressor. The motor of the compressor may be connected to a variable frequency drive (“VFD”). An electronic signal sent to this VFD device would provide fast acting fuel control.
5. A fast-acting actuator driving the variable area turbine nozzle (“VAN”).
6. A multistage turbo-machine, whereby dividing the work of compression and expansion into multiple spools, serves to lower the overall moment of inertia of the machine. This moment of inertia is often referred to as ‘turbo-lag’ in the field of turbochargers. Dividing the work of compression and expansion into multiple spools in a gas turbine has a similar transient behavior benefit.
7. Further reductions in the ‘turbo-lag’ phenomenon are achieved when one or both turbines are fabricated from light-weight ceramic materials.
8. Coupling a variable speed alternator to the free power turbine and coupling the rectified alternator output to an inverter whose impedance can be varied, serves to isolate the speed change of the alternator from the frequency delivered to the power grid (the aforementioned 50, 60 or 400 Hz). This enables the engine to achieve high efficiency at part-power. When an electrical load is applied, starting from any power level, the instantaneous power demand is met first by the low inertia in the high-speed power turbine-alternator assembly, and if needed, by the ultra-capacitor. During that the short transient of 1 to 4 seconds, the aforementioned power turbine dips in speed, but recovers rapidly owing to the behavior previously described. Throughout this transient, the inverter continues to deliver precisely the ISO quality frequency (50 or 60 Hz). The ‘blip’ in power may be made-up by the ultra-capacitor. A large battery might also be used, but it would require a power rating equal to that of the engine's generator, with large associated energy capacity and high cost. Preferably a much smaller ultra-capacitor with capacity to deliver full engine rated power for a few seconds would be less expensive. The power turbine's behavior is such that it changes speed quickly, drooping slightly but rapidly recovering. The integrated energy (power times time) is very small, compared to what a typical battery would provide. The small stored energy is most economically supplied by the ultra-capacitor. While in some block-load (or step-loads) the speed droop may not exceed ISO standards, typically 3% for <3 seconds, in larger load steps, the electrical capacitance can be drawn-upon to make up the power deficit, enabling the inverter to uphold the frequency, without noticeable change. For clarity, any perturbation on the output frequency line would be corrected in one or two cycles. (˜ 1/60th of a second). Since the engine is able to deliver full power at sub-rated power turbine speed, the interruption in delivery of AC power to the grid is minimized.
9. A small resistor bank, typically sized to provide the opposite feature of the aforementioned ultra-capacitor, may be used in instances when power (load) is dropped quickly. This resistor may be installed on the DC or AC link (
The combined benefits of these eight features create a unique engine architecture with exceptionally agile transient behavior in an environment characterized by volatile load shifts.
Furthermore, as compared to the contemporary single shaft engine (
The gas turbine engine shown in
control of the fuel valve for the engine's main fuel flow;
control of the variable area nozzle at the entrance of the free power turbine; and
control of inverter impedance which controls the rpms of the free power turbine.
The proposed gas turbine engine shown in
For example, when the energy storage device is an ultra-capacitor or array of ultra-capacitors, the capacitator or capacitors can be rapidly discharged when a block loading event demanding more power is detected. This rapid injection of electrical power will maintain the required power level while the gas turbine engine is responding, thus further reducing turbo lag and maintaining output power within ISO requirements.
The disclosure has been described with reference to the preferred embodiments. Modifications and alterations will occur to others upon a reading and understanding of the preceding detailed description. It is intended that the disclosure be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
A number of variations and modifications of the disclosures can be used. As will be appreciated, it would be possible to provide for some features of the disclosures without providing others.
The present disclosure, in various embodiments, includes components, methods, processes, systems and/or apparatus substantially as depicted and described herein, including various embodiments, sub-combinations, and subsets thereof. Those of skill in the art will understand how to make and use the present disclosure after understanding the present disclosure. The present disclosure, in various embodiments, includes providing devices and processes in the absence of items not depicted and/or described herein or in various embodiments hereof, including in the absence of such items as may have been used in previous devices or processes, for example for improving performance, achieving ease and\or reducing cost of implementation.
The foregoing discussion of the disclosure has been presented for purposes of illustration and description. The foregoing is not intended to limit the disclosure to the form or forms disclosed herein. In the foregoing Detailed Description for example, various features of the disclosure are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the disclosure.
Moreover though the description of the disclosure has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the disclosure, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.
The present application claims the benefits, under 35 U.S.C.§ 119(e), of U.S. Provisional Application Ser. No. 62/641,119 entitled “Gas Turbine for Block Loading” filed Mar. 9, 2018 which is incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62641119 | Mar 2018 | US |
