An aircraft humidifier is engineered as a stand-alone, fully integrated aircraft humidifier that is suitable for providing uniform, non-wetting humidified air disbursed by the aircraft humidifier into ambient air to increase the relative humidity in low humidity environments such as aircraft interiors, including cockpits, cabins, crew rests, cargo holds, and lavatories as well as any other enclosed areas.

A liquid system for circulating a liquid through a circulation loop includes a liquid pump, a primary liquid reservoir and an auxiliary liquid reservoir. The liquid pump pressurizes liquid within the circulation loop. The primary liquid reservoir has a primary variable volume expandable to accommodate volumetric expansion of pressurized liquid up to a threshold volume. The auxiliary liquid reservoir has an auxiliary variable volume expandable only after the threshold volume is exceeded up to a maximum volume.

A thermal management system for tightly controlling temperature of a thermal load (e.g., onboard an aircraft) includes: a pressurized tank for storing an expendable coolant; a control valve downstream of the pressurized tank for controlling a flow rate of the expendable coolant; a heat exchanger downstream of the control valve for transferring heat from a thermal load to the expendable coolant at a predetermined temperature; a back pressure regulator (BPR) downstream of the heat exchanger, the BPR having a set point controlled to maintain the expendable coolant at the predetermined temperature in the heat exchanger; optionally, a sensor or orifice downstream of the heat exchanger for determining vapor quality at an exit of the heat exchanger; and a system exit downstream of the BPR for removing some or all of the expendable coolant from the thermal management system after transferring heat from the thermal load to the expendable coolant.

The disclosure describes a system that includes an evaporator, an accumulator downstream of the evaporator, a centrifugal compressor downstream of the accumulator, a first heat exchanger stage downstream of the centrifugal compressor, and a second heat exchanger stage downstream of the first heat exchanger stage. The evaporator is configured to cool a conditioned air stream using a refrigerant. The accumulator is configured to store excess refrigerant. The centrifugal compressor is configured to compress the refrigerant. The first heat exchanger stage is configured to cool the refrigerant using environmental air. The second heat exchanger stage is configured to cool the refrigerant from the first heat exchanger stage using a portion of the excess refrigerant from the accumulator.

An aircraft air conditioning system includes a lower cooling zone and an upper cooling zone. The lower cooling zone includes a lower recirculation heat exchanger configured to receive cabin air from a cabin and convert the cabin air into lower cooled recirculated cabin air. The upper cooling zone includes an upper recirculation heat exchange configured to receive the cabin air from the cabin and convert the cabin air into upper cooled recirculated cabin air. A power system selectively delivers power to the lower cooling zone and the upper cooling zone. A controller is in signal communication with the power system. The controller determines a target temperature of the cabin and invokes a recirculation ground maintenance mode that commands the power system to deliver power to one or both of the lower cooling zone and the upper cooling zone so that a temperature of the cabin reaches the target temperature.

The system can include an on-board thermal management subsystem. The system 100 can optionally include an off-board (extravehicular) infrastructure subsystem. The on-board thermal management subsystem can include: a battery pack, one or more fluid loops, and an air manifold. The system 100 can additionally or alternatively include any other suitable components.

A vehicle cabin air temperature controller includes a two-position three-way solenoid valve with one inlet to take in coolant supplied by a pump, a first outlet to supply a cooling leg, and a second outlet to supply a bypass leg. The vehicle cabin air temperature controller also includes a controller to control flow of the coolant via the first outlet and the second outlet of the solenoid valve, and a cabin air heat exchanger to obtain an input coolant based on the control of the flow via the first outlet and the second outlet and to provide cooled cabin air to the vehicle cabin. The control of the flow of the coolant via the first outlet and the second outlet controls a flow rate of the input coolant.

An environmental control system (ECS) for use with a gas turbine engine has an air cycle system (ACS) and a vapor cycle system (VCS). The VCS has along a vapor compression flowpath: a VCS compressor; a heat donor leg of a VCS condenser; an expansion device; and a heat receiving leg of a VCS evaporator. The ACS has along a bleed flowpath: a bleed air inlet; a primary heat exchanger; an ACS compressor; a secondary heat exchanger; a turbine coupled to the ACS compressor to drive the ACS compressor; a heat donor leg of the VCS evaporator; a water collector; and a heat receiving leg of the VCS condenser.

An outer panel-mediated cooling system includes: an outer shell including an outer panel, an inner panel located inward of the outer panel, and a heat-insulating layer located between the outer and inner panels; a cooling chamber that is located between the outer and inner panels and in which a gas releases heat outside through the outer panel and is thus cooled; a circulation loop in which a heat medium circulates, the circulation loop including a heating section located inward of the inner panel to heat the heat medium and a cooling section located in the cooling chamber to cool the heat medium; a flow path-forming structure located in the cooling chamber to form a circulation path for the gas; and a fan located in the cooling chamber to exert a drive force on the gas to allow the gas to circulate in the circulation path.

An evaporator that receives heat from a heat generator to change at least part of a working fluid from a liquid phase to a gas phase includes: a housing including an accommodation chamber that accommodates the working fluid; and a heat receiver located on a bottom surface of the housing and thermally connected to the heat generator. The housing includes: a porous plate dividing the accommodation chamber into an upper chamber and a lower chamber and including a large number of pores through which the upper and lower chambers communicate with each other; at least one working fluid inlet opening into the upper chamber; a partition dividing a bottom of the lower chamber into liquid retainers; and at least one working fluid outlet opening into the lower chamber and located above the partition.