Provided herein are an austenite steel that satisfies desirable strength and desirable castability at the same time, and an austenite steel casting using same. The austenite steel according to an embodiment of the present invention contains Ni: 25 to 50%, Nb: 3.8 to 6.0%, Zr: 0.5% or less, B: 0.001 to 0.05%, Cr: 12 to 25%, Ti: 1.6% or less, Mo: 4.8% or less, and W: 5.2% or less in mass %, and the balance Fe and unavoidable impurities, wherein the parameter Ps represented by the following formula (1) satisfies Ps38,
Ps=8.3[Nb]7.5[Ti]+2.4[Mo]+3.5[W]formula (1),
where [Nb], [Ti], [Mo], and [W] represent the contents of Nb, Ti, Mo, and W, respectively, in mass %.

A heat engine, in particular an ORC engine, includes a crankcase and at least one working cylinder connected to the crankcase, in which cylinder a working piston that is rigidly connected to a piston rod can be moved and the end of the piston rod facing away from the working piston is articulatedly connected to a connecting rod by a crosshead running in the longitudinal direction of the piston rod. The interior of the working cylinder, which is supplied with a working medium, is separated from the interior of the crankcase, which is supplied with oil, by two walls, each of which has a sealing through-opening for the piston rod.

Systems and methods for cooling a power generation working fluid are disclosed that reduce the amount of cooling fluid used. These systems and methods save on water usage in the generation of power by thermoelectric power generation systems.

Implementations described and claimed herein provide systems and methods for providing energy to a defined space, such as a house or other building. In one implementation, thermal energy is received from a solar power source at a solar boiler, and steam is generated from the thermal energy using the solar boiler. One or pistons of a steam engine is driven with a pressure from the steam. The steam engine outputs a first waste heat. The first waste heat is received from the steam engine at a chiller. The chiller generates conditioned air from the first waste heat.

A double turbine exhaust duct design and an inline V turbine exhaust duct design that both eliminate the need for the standard T-piece in a turbine exhaust duct assembly, substantially reducing the steam-side pressure drop, minimizing the sub-cooling in the steam cycle (the temperature difference between ACC condensate temperature out and turbine steam temperature), thus improving the overall efficiency of the steam cycle plant heat rate.

A double turbine exhaust duct design and an inline V turbine exhaust duct design that both eliminate the need for the standard T-piece in a turbine exhaust duct assembly, substantially reducing the steam-side pressure drop, minimizing the sub-cooling in the steam cycle (the temperature difference between ACC condensate temperature out and turbine steam temperature), thus improving the overall efficiency of the steam cycle plant heat rate.

A free piston device, comprises a housing with a cylindrical inner wall having a first wall opening and a second wall opening; a cylindrical piston movable in axial direction and rotatable around its longitudinal axis; the piston comprising a first skirt forming a first chamber, said first skirt having at least a first opening in the form of a hole through the wall of the skirt for allowing passage of a fluid directly into or out of said chamber; control means for controlling axial and angular movement of said piston; sensing means for providing signals related to the axial position and/or the angular position of the piston; a digital control unit for rotating the piston around its longitudinal axis in synchronism with its axial movement.

System (2) for carrying out a gas based thermodynamic cycle in which a gas is compressed in at least one compressor (8) in one part of the cycle and is expanded in at least one expander (10) operating simultaneously in an upstream or downstream part of the cycle, wherein the change in absolute internal power with gas mass flow rate differs as between the compressor and the expander and wherein the system comprises a control system configured to make selective adjustments so as individually to control, either directly or indirectly, the respective gas mass flow rates through each of the compressor and expander. The system may be an energy storage system including a pumped heat energy storage system configured to provide independent graduated control of system pressure and output power by selective adjustment of the respective gas mass flow rates through each half-engine.

System (2) for carrying out a gas based thermodynamic cycle in which a gas is compressed in at least one compressor (8) in one part of the cycle and is expanded in at least one expander (10) operating simultaneously in an upstream or downstream part of the cycle, wherein the change in absolute internal power with gas mass flow rate differs as between the compressor and the expander and wherein the system comprises a control system configured to make selective adjustments so as individually to control, either directly or indirectly, the respective gas mass flow rates through each of the compressor and expander. The system may be an energy storage system including a pumped heat energy storage system configured to provide independent graduated control of system pressure and output power by selective adjustment of the respective gas mass flow rates through each half-engine.

Provided herein are rotary valve assemblies, engines, and corresponding methods. A rotary valve assembly may include a valve housing defining a cylindrical bore, an inlet, and an outlet. The valve assembly may further include an intake assembly and a throttle assembly arranged concentrically within the cylindrical bore of the valve housing, and the intake assembly and the throttle assembly may rotate independently of one another with respect to a longitudinal axis. During operation of the rotary valve assembly, the valve housing may permit fluid to enter the cylindrical bore of the valve housing via the inlet, the intake assembly may rotate to permit the fluid to flow through the at least one intake inlet port and the at least one throttle inlet port into the throttle body, and the intake assembly may permit the fluid to flow to the outlet from the throttle body.