A convertible ducted fan engine and mounting system. The convertible ducted fan engine has a shroud encircling a mechanical fan. The convertible ducted fan engine includes a fluid-propulsion configuration in which the mechanical fan rotates freely with respect to the shroud to produce thrust through fluid flow, and a drive-wheel configuration in which the shroud rotates about the rotational axis.

The amount of consumption of gas is reduced when the gas is expanded to be cooled by using a plurality of expansion turbines. A high-pressure expansion turbine includes: a gas supply passage through which bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. A low-pressure expansion turbine includes: a gas supply passage through which the bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. The bearing gas discharged from the gas discharge passage of the high-pressure expansion turbine is supplied to the gas supply passage of the low-pressure expansion turbine.

The amount of consumption of gas is reduced when the gas is expanded to be cooled by using a plurality of expansion turbines. A high-pressure expansion turbine includes: a gas supply passage through which bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. A low-pressure expansion turbine includes: a gas supply passage through which the bearing gas is supplied to a bearing portion; and a gas discharge passage through which the bearing gas which has been supplied from the gas supply passage to the bearing portion is discharged from the bearing portion. The bearing gas discharged from the gas discharge passage of the high-pressure expansion turbine is supplied to the gas supply passage of the low-pressure expansion turbine.

A steam turbine plant is provided with: a boiler; a fuel valve; a low-temperature steam generation source; a steam turbine; a main steam line that guides steam generated in the boiler to the steam turbine; a main steam adjustment valve that is provided to the main steam line; a low-temperature steam line that guides low-temperature steam from the low-temperature generation source to a position closer to the steam turbine-side than the main steam adjustment valve in the main steam line; a low-temperature steam valve provided to the low-temperature steam line; and a control device. During a stopping process of the steam turbine plant, the control device sends a command to close the fuel valve, and then sends a command to open the low-temperature steam valve.

A steam turbine plant is provided with: a boiler; a fuel valve; a low-temperature steam generation source; a steam turbine; a main steam line that guides steam generated in the boiler to the steam turbine; a main steam adjustment valve that is provided to the main steam line; a low-temperature steam line that guides low-temperature steam from the low-temperature generation source to a position closer to the steam turbine-side than the main steam adjustment valve in the main steam line; a low-temperature steam valve provided to the low-temperature steam line; and a control device. During a stopping process of the steam turbine plant, the control device sends a command to close the fuel valve, and then sends a command to open the low-temperature steam valve.

An engine-driven cryogenic cooling system for an aircraft includes a first air cycle machine, a second air cycle machine, and a means for condensing a chilled air stream into liquid air for an aircraft use. The first air cycle machine includes a plurality of components operably coupled to a gearbox of a gas turbine engine and configured to produce a cooling air stream based on a first engine bleed source of the gas turbine engine. The second air cycle machine is operable to output the chilled air stream at a cryogenic temperature based on a second engine bleed source cooled by the cooling air stream of the first air cycle machine.

An engine-driven cryogenic cooling system for an aircraft includes a first air cycle machine, a second air cycle machine, and a means for condensing a chilled air stream into liquid air for an aircraft use. The first air cycle machine includes a plurality of components operably coupled to a gearbox of a gas turbine engine and configured to produce a cooling air stream based on a first engine bleed source of the gas turbine engine. The second air cycle machine is operable to output the chilled air stream at a cryogenic temperature based on a second engine bleed source cooled by the cooling air stream of the first air cycle machine.

A system and method for cooling an oxygen stream by heat exchange with a warming supply nitrogen stream having of a heat exchanger having at least a Zone A and a Zone B, the system having indirect heat exchange between a gaseous oxygen stream, and a high-pressure liquid nitrogen stream split into at least a first portion which passes through a Zone A, and a second portion which passes through a Zone B during a first phase of operation. And a high-pressure liquid nitrogen stream passing through Zone A, thereby producing a high-pressure nitrogen vapor stream, which passes through an expansion turbine, thereby producing an expansion turbine outlet stream which then passes through Zone B, during a second phase of operation, thereby producing a liquid oxygen stream.

Various configurations of a power plant are described. The power plant is configured to supply power to a receiving electrical grid by the combustion of metal powder. The power plant is also configured absorb power by recovering the metal powder from the metal oxide produced by the combustion of the metal powder, with electricity from a source electrical grid.

A turbomachine system includes a turbomachine provided with a turbomachine rotor. The turbomachine rotor is comprised of a turbomachine shaft with a first shaft end and a second shaft end. The turbomachine shaft is supported by active magnetic bearings for rotation in a turbomachine casing. The turbomachine system further includes a rotary machine drivingly coupled to the first shaft end, and a first closed cooling circuit adapted to circulate a cooling fluid therein and fluidly coupled to the active magnetic bearings to remove heat therefrom. The closed cooling circuit includes a cooling fluid impeller mounted on the turbomachine shaft for rotation therewith and adapted to circulate the cooling fluid in the closed cooling circuit. The closed cooling circuit further includes a heat exchanger adapted to remove heat from the cooling fluid. A method of operating a turbomachine system is further disclosed.