The present application relates to a heat recovery apparatus and method. According to the heat recovery apparatus and method, low-level heat sources at a temperature less than 100 C. discharged from industrial settings or various chemical processes, for example, a petrochemicals manufacturing process are not wasted but used to generate steam and the generated steam is used for various processes to reduce an amount of consumed high-temperature steam that is an external heat source to be used for a reactor or distillation column, thereby not only maximizing energy reduction efficiency but also autonomously producing power consumed by a compressor. Also, an evaporation phenomenon of a part of a refrigerant flow which passes through the compressor may be reduced, thereby recovering heat with excellent efficiency.

Using various embodiments, methods and systems for cooling a data center using recovered thermal energy are described. In one embodiment, a data center cooling system comprises a first channel conveying a cooling fluid received from an outlet of a ventilation system of the computer data center at a first temperature, a second channel conveying the cooling fluid provided into an inlet of the ventilation system to cool the data center at a second temperature, and a heat transfer subsystem (HTS) configured to operate in an organic Rankine cycle (ORC) or a gas compression cycle (GCC) to change the temperature of the cooling fluid from the first temperature to the second temperature. In another embodiment, the system includes a monitoring subsystem monitoring a temperature, pressure, or flow of a working-fluid of the HTS and a controller subsystem to determine whether to operate the HTS in the ORC or GCC modes.

A thermal management system comprises a first heat exchanger configured to exchange heat between a first component and a first working fluid, a first working fluid compressor downstream in first working fluid flow of the first heat exchanger and configured to compress the first working fluid, a second heat exchanger downstream in first working fluid flow of the compressor and configured to exchange heat between the first working fluid and a second working fluid and an expander downstream in first working fluid flow of the second heat exchanger, and configured to expand and cool first working fluid and deliver cooled first working fluid to the first heat exchanger. The system further comprises a third heat exchanger upstream in second working fluid flow of the second heat exchanger, and configured to exchange heat between a second component and the second working fluid.

A thermal management system comprises a first heat exchanger configured to exchange heat between a first component and a first working fluid, a first working fluid compressor downstream in first working fluid flow of the first heat exchanger and configured to compress the first working fluid, a second heat exchanger downstream in first working fluid flow of the compressor and configured to exchange heat between the first working fluid and a second working fluid and an expander downstream in first working fluid flow of the second heat exchanger, and configured to expand and cool first working fluid and deliver cooled first working fluid to the first heat exchanger. The system further comprises a third heat exchanger upstream in second working fluid flow of the second heat exchanger, and configured to exchange heat between a second component and the second working fluid.

Disclosed is a low-temperature refrigeration device comprising a working circuit that forms a loop and contains a working fluid the working circuit forming a cycle which includes, connected in series: a compression mechanism, a cooling mechanism, an expansion mechanism and a heating mechanism, the device further comprising a refrigeration heat exchanger for extracting heat from at least one member by exchanging heat with the working fluid flowing in the working circuit, the compression mechanism comprising two separate compressors, the mechanism for cooling the working fluid comprising two cooling heat exchangers which are arranged respectively at the outlet of the two compressors and ensure heat exchange between the working fluid and a cooling fluid, each cooling heat exchanger comprising a cooling fluid inlet and a cooling fluid outlet, characterized in that the cooling fluid outlet of one of the two cooling heat exchangers is connected to the cooling fluid inlet of the other cooling heat exchanger.

A cooling subsystem of a fuel cell assembly that employs the Rankine cycle to use the potential energy of a thermally pressurized fluid to generate electrical power. Waste heat from a fuel cell stack is transferred to working fluid in a heat exchanger. The working fluid in the condensed phase is pressurized, evaporated in a boiler or evaporator, and then fed to an expansion turbine which in turn provides rotary motion to an electric generator to generate useful electrical power. The fluid leaves the turbine as a lower pressured vapor, and is then condensed back to a fluid and pumped back to the evaporator to repeat the process.

A cooling subsystem of a fuel cell assembly that employs the Rankine cycle to use the potential energy of a thermally pressurized fluid to generate electrical power. Waste heat from a fuel cell stack is transferred to working fluid in a heat exchanger. The working fluid in the condensed phase is pressurized, evaporated in a boiler or evaporator, and then fed to an expansion turbine which in turn provides rotary motion to an electric generator to generate useful electrical power. The fluid leaves the turbine as a lower pressured vapor, and is then condensed back to a fluid and pumped back to the evaporator to repeat the process.

An expander and motor-compressor unit is disclosed. The unit includes a casing and an electric motor arranged in the casing. A compressor is arranged in the casing and drivingly coupled to the electric motor through a central shaft. Furthermore, a turbo-expander is arranged for rotation in the casing and is drivingly coupled to the electric motor and to the compressor through the central shaft.

An expander and motor-compressor unit is disclosed. The unit includes a casing and an electric motor arranged in the casing. A compressor is arranged in the casing and drivingly coupled to the electric motor through a central shaft. Furthermore, a turbo-expander is arranged for rotation in the casing and is drivingly coupled to the electric motor and to the compressor through the central shaft.

An air cycle machine comprises rotating components that include a fan, a compressor, and a first turbine. The air cycle machine also includes a cooling airflow path that receives cooling air from a cooling air source, directs the cooling air to an air-cooled bearing for at least one of the rotating components, and discharges the cooling air. The airflow path is isolated from an inlet of the compressor by a seal member, and the airflow path is configured to maintain pressure at the seal member above a pressure at the compressor inlet.