A fuel tank inerting system is provided including an air flow comprising air from a first source having a first temperature and air from a second source having a second temperature. The second temperature is cooler than the first temperature. At least one separating module is configured to separate an inert gas from the air flow.

An aircraft environmental control system includes a tank holding cryogenic fuel, a heat exchanger, a first rotary machine, a first outlet duct, and a second outlet duct. The heat exchanger includes a cold side flow path downstream from the tank to evaporate the fuel, a first hot side flow path, and a second hot side flow path. The first rotary machine includes a first compressor section with an impeller upstream from the second hot side flow path. The first rotary machine includes a first shaft tied to the impeller and a first motor to rotate the impeller. The first duct and the second duct are downstream from the heat exchanger. The first duct provides a first portion of vaporized fuel to a power generator. The second duct provides a second portion of vaporized fuel to a burner that creates hot air to move through the first hot side flow path.

An aircraft environmental control system includes a tank holding liquid fuel, a heat exchanger, a first rotary machine, and a second rotary machine. The heat exchanger includes a cold side flow path downstream from the tank to vaporize the fuel using hot fluids from the aircraft. The heat exchanger includes a first hot side flow path and a second hot side flow path to cool the hot fluids. The first rotary machine includes a first compressor with a first impeller upstream from the second hot side flow path. The first rotary machine includes a first shaft tied to the first impeller and a first motor, which rotates the first impeller. The second rotary machine includes a second compressor with a second impeller downstream from the first compressor section. The second rotary machine includes a second shaft tied to the second impeller and a second motor, which rotates the second impeller.

An environmental control system includes a cooling circuit having at least one heat exchanger for cooling a first medium therein. At least one compressing device is operably coupled to the cooling circuit. The at least one compressing device includes a first compressor and a second compressor, wherein the first medium is provided to the first compressor and the second compressor in series, and a temperature of the first medium provided to an inlet of the second compressor is less than the temperature of the first medium at an outlet of the first compressor.

A ram air system includes a bay comprising an exterior wall defining an interior volume that at least partially encloses a ram air duct. The ram air duct includes an outlet configured to discharge an exhaust airflow at a first temperature. At least one of the exterior wall and the ram air duct defines an aperture therein providing for flow communication between the bay interior volume and the exhaust airflow such that cooling air flows from the interior volume to form a boundary layer between the exhaust airflow and the exterior wall downstream of the outlet. The boundary layer is at a second temperature that is lower than the first temperature.

A method for combined cooling and heating in an aircraft, the aircraft including an engine configured to use dihydrogen as fuel, the dihydrogen being stored in liquid form in a tank and being used in gas form in the engine, the dihydrogen being conveyed from the tank to the engine by a main pipe. The method includes the steps of branching off a part of the flow of dihydrogen in a bypass pipe, in parallel with a predefined segment of the main pipe, circulating a first heat transfer fluid in a first closed circuit, carrying out a first heat exchange between the first heat transfer fluid and the dihydrogen circulating in the bypass pipe and carrying out at least one secondary heat exchange. Each secondary heat exchange is carried out between the first heat transfer fluid and a working fluid used in the aircraft which needs to be cooled.

An aircraft thermal management system comprising a high temperature loop and a low temperature loop. The high temperature loop is configured to manage a temperature of a fuel cell stack in a nacelle using a nacelle heat exchanger. The low temperature loop is configured to cool a number of heat loads in a nacelle using a heat capacity of liquid hydrogen.

A cooling system in which an ACS (air cycle system) turbine may be driven by high pressure air from a turbo-fan engine and a VCS (vapor cycle system) having an evaporator and a VCS refrigerant compressor may be driven by the ACS turbine. Fluid of the chilled fluid reservoir, which may be chilled fuel, may be circulated through and cooled in the evaporator. In some embodiments, the ACS turbine may be coupled to the VCS refrigerant compressor by a magnetic coupling.

The present disclosure relates generally to a system for removing fuel from a mixture of air and fuel vapor in an ullage space of an aircraft fuel tank. The system includes a compressor for drawing the mixture of air and fuel vapor from the ullage space and directing the mixture of air and fuel vapor through a heat exchanger where the mixture of air and fuel vapor is cooled. The system also includes a turbine configured to be driven by the mixture of air and fuel from the heat exchanger. Power from the turbine can be transferred back toward the compressor to assist in driving rotation of the compressor. The system further includes a separator for receiving the mixture of air and fuel vapor from the turbine and separating at least some liquid fuel from the mixture of air and fuel vapor. From the separator, a separated liquid fuel and a mixture of air and fuel vapor with reduced concentration of fuel vapor are returned to the aircraft fuel tank.

A system for an aircraft includes an engine bleed source of a gas turbine engine. The system also includes a means for chilling an engine bleed air flow from the engine bleed source to produce a chilled working fluid. The system further includes a means for providing the chilled working fluid for an aircraft use.