A gas turbine engine has a compressor section, a combustor, and a turbine section. An associated fluid is to be cooled and an associated fluid is to be heated. A transcritical vapor cycle heats the fluid to be heated, and cools the fluid to be cooled. The transcritical vapor cycle includes a gas cooler in which the fluid to be heated is heated by a refrigerant in the transcritical vapor cycle. An evaporator heat exchanger at which the fluid to be cooled is cooled by the refrigerant in the transcritical vapor cycle. A compressor upstream of the gas cooler compresses the refrigerant to a pressure above a critical point for the refrigerant. An expansion device expands the refrigerant downstream of the gas cooler, with the evaporator heat exchanger being downstream of the expansion device, and such that the refrigerant passing through the gas cooler to heat the fluid to be heated is generally above the critical point.

A turbomachine engine including a high-pressure compressor, a high-pressure turbine, a combustion chamber in flow communication with the high-pressure compressor and the high-pressure turbine, and a power turbine in flow communication with the high-pressure turbine. At least one of the high-pressure compressor, the high-pressure turbine, and the power turbine comprises a ceramic matrix composite (CMC) material. The turbomachine engine includes a low-pressure shaft coupled to the power turbine and characterized by a midshaft rating (MSR) between two hundred (ft/sec).sup.1/2 and three hundred (ft/sec).sup.1/2. The low-pressure shaft has a redline speed between fifty and two hundred fifty feet per second (ft/sec). The turbomachine engine is configured to operate up to the redline speed without passing through a critical speed associated with a first-order bending mode of the low-pressure shaft.

A turbomachine engine including a high-pressure compressor, a high-pressure turbine, a combustion chamber in flow communication with the high-pressure compressor and the high-pressure turbine, and a power turbine in flow communication with the high-pressure turbine. At least one of the high-pressure compressor, the high-pressure turbine, and the power turbine comprises a ceramic matrix composite (CMC) material. The turbomachine engine includes a low-pressure shaft coupled to the power turbine and characterized by a midshaft rating (MSR) between two hundred (ft/sec).sup.1/2 and three hundred (ft/sec).sup.1/2. The low-pressure shaft has a redline speed between fifty and two hundred fifty feet per second (ft/sec). The turbomachine engine is configured to operate up to the redline speed without passing through a critical speed associated with a first-order bending mode of the low-pressure shaft.

A gas turbine engine includes a first spool associated with a diffuser and a primary combustor and a second spool associated with a secondary combustor. The first spool includes a first compressor and a first turbine mounted to a first shaft, and the second spool includes a second compressor and a second turbine mounted to a second shaft. An inlet duct fluidly connects the diffuser to the second compressor. An outlet duct assembly fluidly connects the second turbine to the diffuser and the primary combustor.

A gas turbine engine includes a first spool associated with a diffuser and a primary combustor and a second spool associated with a secondary combustor. The first spool includes a first compressor and a first turbine mounted to a first shaft, and the second spool includes a second compressor and a second turbine mounted to a second shaft. An inlet duct fluidly connects the diffuser to the second compressor. An outlet duct assembly fluidly connects the second turbine to the diffuser and the primary combustor.

An energy extraction system according to an exemplary embodiment of this disclosure, among other possible things includes an ammonia fuel storage tank assembly that is configured to store a liquid ammonia fuel, a thermal transfer assembly that is configured to transform the liquid ammonia fuel into a vaporized ammonia based fuel, a turbo-expander that is configured to expand the vaporized ammonia based fuel to extract work, and an energy conversion device that is configured to use the vaporized ammonia based fuel from the turbo-expander to generate a work output.

An energy extraction system according to an exemplary embodiment of this disclosure, among other possible things includes an ammonia fuel storage tank assembly that is configured to store a liquid ammonia fuel, a thermal transfer assembly that is configured to transform the liquid ammonia fuel into a vaporized ammonia based fuel, a turbo-expander that is configured to expand the vaporized ammonia based fuel to extract work, and an energy conversion device that is configured to use the vaporized ammonia based fuel from the turbo-expander to generate a work output.

The present disclosure describes an improved vehicle wheel rotation apparatus. The apparatus 300 comprises a combustion chamber 301, one or more turbines (302,311) and at least one non-return valve 306. An auxiliary attachment 305 is retrofitted at surface of each bar 304 present in each turbine. The auxiliary attachment 305 comprises 3-tube arrangement, wherein two tubes (305a, 305b) of the attachment 305 enable entry of jet of exhaust gases into the attachment 305 and further facilitate the plurality of bars 304 for initiating rotation of the runner 303. The jet of exhaust gases, exiting the attachment 305 through last tube 305c, comprises reducing cross-section near opening, enabling further increment in velocity of exhaust gas, resulting in thrust to the bar 304 to which the attachment 305 is already fitted, thus providing additional rotations to the runner 303 and eventually to one or more wheels of the vehicle.

The present disclosure describes an improved vehicle wheel rotation apparatus. The apparatus 300 comprises a combustion chamber 301, one or more turbines (302,311) and at least one non-return valve 306. An auxiliary attachment 305 is retrofitted at surface of each bar 304 present in each turbine. The auxiliary attachment 305 comprises 3-tube arrangement, wherein two tubes (305a, 305b) of the attachment 305 enable entry of jet of exhaust gases into the attachment 305 and further facilitate the plurality of bars 304 for initiating rotation of the runner 303. The jet of exhaust gases, exiting the attachment 305 through last tube 305c, comprises reducing cross-section near opening, enabling further increment in velocity of exhaust gas, resulting in thrust to the bar 304 to which the attachment 305 is already fitted, thus providing additional rotations to the runner 303 and eventually to one or more wheels of the vehicle.

A gas turbine engine including: an exhaust diffuser including an inner tube and an outer tube that form therebetween an annular exhaust passage; a bearing chamber formed radially inside the inner tube for accommodating a bearing that supports a rotor of a turbine; a plurality of hollow struts extending across the exhaust passage; an oil introduction passage extending through one of the struts for introducing oil to be supplied to the bearing chamber; an oil drain passage extending through one of the struts for draining the oil from an exhaust oil inlet opened on a bottom surface of the bearing chamber; and an oil discharge passage for discharging a portion of the oil having passed through the oil introduction passage toward the oil drain inlet.