An environmental control system of a vehicle including a first inlet for providing a first medium, a second inlet for providing a second medium, a compression device arranged in fluid communication with the first inlet, and an expansion device separate from the compression device. The expansion device is arranged in fluid communication with the second inlet. Energy extracted from the second medium within the expansion device is provided to one or more loads of the vehicle.

A pressurization system includes a first compressor that receives a ram air, a fan air, or engine air; a first turbine that is on a common shaft with the first compressor and wherein the first turbine receives an engine air; a main heat exchanger downstream of the first compressor and the first turbine; an internal environment suitable for human occupants and downstream of the main heat exchanger; a second turbine downstream of the internal environment; the second turbine may be on the common shaft with the first compressor and first turbine; or a generator downstream of the second turbine; a motor downstream of the generator; and wherein the motor drives the first compressor.

An air conditioning pack of a cooling system includes an air cycle machine assembly, a cabin air compressor assembly, and a mixing duct. The air cycle machine assembly includes a compressor configured to receive an air stream that includes bleed air to generate a compressed air stream. The air cycle machine assembly utilizes a first portion of the compressed air stream to power the compressor. The cabin air compressor assembly receives a second portion of the compressed air stream, and utilizes the second portion to generate compressed ram air. The mixing duct receives the compressed ram air and allows the compressed ram air to mix with one or more of the air stream upstream of the compressor or the compressed air stream downstream of the compressor to generate a hybrid air stream that is used for cooling at least a portion of a vehicle.

Systems to produce cabin supply air for aircraft and related methods are described herein. An example system includes an air conditioning pack including a heat exchanger including a first flow path and a second flow path isolated from the first flow path. The second flow path is to receive cabin exhaust air from a cabin of an aircraft. The cabin exhaust air is to reduce a temperature of the cabin supply air flowing through the first flow path of the heat exchanger. The system also includes a turbine to receive the cabin supply air from the heat exchanger. The turbine is to reduce a temperature and pressure of the cabin supply air. A turbine outlet of the turbine is fluidly coupled to the cabin to provide the cabin supply air to the cabin. The system further includes a fan to direct the cabin exhaust air from the heat exchanger.

Disclosed is an air cycle machine (ACM) having: a turbine; a compressor; a compressor shaft connected to the compressor and configured to receive rotational energy from a gearbox; and a turbine shaft connected to the turbine and configured to provide rotational energy to the gearbox; wherein the turbine shaft and the compressor shaft operate at different rotational speeds.

A system includes a first fluid flow path configured to condition a pressurized medium and deliver the pressurized medium to one or more loads. The first fluid flow path including an air cycle machine. A second fluid flow path is configured to circulate a working fluid. The second fluid flow path includes a heat exchanger thermally coupled to the first fluid flow path. Within the heat exchanger, heat extracted from the pressurized medium is transferred to the working fluid. The second fluid flow path additionally includes a turbine operably coupled to the air cycle machine, a condenser, and a pump operable to circulate the working fluid through at least a portion of the second fluid flow path. The turbine is rotationally driven by expanding the working fluid across the turbine.

A dual entry turbine of a compression device includes a housing having a first inlet and a second inlet, and a first outlet and a second outlet. A turbine impeller is arranged within the housing. The turbine impeller has a first gas path and a second gas path. A first flow path extends from the first inlet to the first outlet via the first gas path and a second flow path extends from the second inlet to the second outlet via the second gas path. The first flow path and the second flow path being fluidly separate from one another.

An environmental control system comprising that utilizes recirculation air. The environmental control system includes an inlet configured to supply bleed air at a first energy from a source to the environmental control system, where the environmental control system supplies the bleed air at a second energy to a chamber. The environmental control system also includes an air cycle machine comprising a compressor and a turbine, where the air cycle machine receives the recirculation air from the chamber and the recirculation air is bleed air at a third energy flowing from the chamber to the air cycle machine.

A system and method that comprises an air cycle machine, a flow of bleed air, at least one heat exchanger, and an inlet configured to supply the flow of the bleed air is provided. The bleed air directly flows from a source to mix with recirculated air downstream of a compressor of the air cycle machine in accordance with a high pressure mode or a recirculation chilling mode. The system and method can also utilize the recirculated air flowing from the chamber to drive or maintain the air cycle machine in accordance with the above modes.

An aircraft air conditioning system comprising an ambient air supply line having a first end connected to an ambient air inlet and a second end connected to a mixer of the aircraft air conditioning system so as to supply ambient air to the mixer. A first compressor is arranged in the ambient air supply line and is configured to compress the ambient air flowing through the ambient air supply line. A bleed air supply line allows a flow of bleed air bled off from an engine or an auxiliary power unit therethrough. A bleed air turbine is driven by the bleed air flowing through the bleed air supply line and is coupled to the first compressor so as to drive the first compressor.