A flowmeter for gaseous fluid includes a conduit composed of non-electrically conductive material for passage of an ionized flow of the gaseous fluid therethrough. The flowmeter further includes an electromagnetic sensor arranged to measure a magnetic field generated about the conduit by the passage of the ionized flow and generate a signal proportional to the magnetic field.

Aircraft fuel system including a fuel vessel containing a non-mixture fuel. A protective vessel is arranged about the fuel vessel such that the fuel vessel is contained within the protective vessel and a protective space is defined between an outer surface of a vessel wall of the fuel vessel and an inner surface of a vessel wall of the protective vessel. At least one mounting structure fixedly positions the fuel vessel within the protective vessel. A fuel consumption device configured to consume the non-mixture fuel. A fuel output fluidly connects an interior of the fuel vessel to the fuel consumption device, the fuel output being fluidly isolated from the protective space. A relief output fluidly connects the protective space to a relief flow path, the relief output and relief flow path configured to vent gas from the protective space and remove any non-mixture fuel from the protective space.

Aircraft fuel system including a fuel vessel containing a non-mixture fuel. A protective vessel is arranged about the fuel vessel such that the fuel vessel is contained within the protective vessel and a protective space is defined between an outer surface of a vessel wall of the fuel vessel and an inner surface of a vessel wall of the protective vessel. At least one mounting structure fixedly positions the fuel vessel within the protective vessel. A fuel consumption device configured to consume the non-mixture fuel. A fuel output fluidly connects an interior of the fuel vessel to the fuel consumption device, the fuel output being fluidly isolated from the protective space. A relief output fluidly connects the protective space to a relief flow path, the relief output and relief flow path configured to vent gas from the protective space and remove any non-mixture fuel from the protective space.

A system and method for using a fuel with an engine, an airframe having an aircraft heat load, a fuel tank, and a fuel oxygen reduction unit are provided. The method includes receiving an inlet fuel flow in the fuel oxygen reduction unit for reducing an amount of oxygen in the inlet fuel flow; separating a fuel/gas mixture within the fuel oxygen reduction unit into an outlet gas flow and an outlet fuel flow exiting the fuel oxygen reduction unit; controlling a first portion of the outlet fuel flow to the engine; and controlling a second portion of the outlet fuel flow to the airframe to transfer heat between the second portion of the outlet fuel flow and the aircraft heat load.

A heat exchanger comprises an inlet, an outlet, a heat exchanging channel, and an opening. The heat exchanging channel surrounds a cavity. The opening provides access to the cavity. The inlet is coupled to one end of the heat exchanging channel and the outlet is coupled to another end of the heat exchanging channel. The heat exchanging channel is isolated from the cavity. No access or passage is present between the heat exchanging channel and the cavity. During operation, heat exchanging fluid flows through the heat exchanging channel thereby cooling fluid within the cavity. The heat exchanging fluid never contacts the fluid within the cavity. In various embodiments, the heat exchanging channel has a single or stacked layer when viewed along a cross section. The heat exchanging channel has a spherical, cylindrical, or rectangular shape. In one embodiment, an insulative layer is disposed between layers of the heat exchanging channel.

Aircraft systems including a pressurized fuel tank containing a pressurized fuel, a turbo expander configured to receive the pressurized fuel from the fuel tank, the turbo expander configured to decrease a pressure of the pressurized fuel to generate low pressure fuel having pressure less than the pressurized fuel, a fuel-to-air heat exchanger configured to receive the low pressure fuel from the turbo expander as a first working fluid and air as a second working fluid, the heat exchanger configured to cool the air and warm the fuel, an aircraft cabin configured to receive the cooled air, and a fuel consumption system configured to consume the fuel to generate power.

Aircraft systems including a pressurized fuel tank containing a pressurized fuel, a turbo expander configured to receive the pressurized fuel from the fuel tank, the turbo expander configured to decrease a pressure of the pressurized fuel to generate low pressure fuel having pressure less than the pressurized fuel, a fuel-to-air heat exchanger configured to receive the low pressure fuel from the turbo expander as a first working fluid and air as a second working fluid, the heat exchanger configured to cool the air and warm the fuel, an aircraft cabin configured to receive the cooled air, and a fuel consumption system configured to consume the fuel to generate power.

An enclosure containing an inerting gas and at least one liquid to be discharged. This enclosure comprises at least one orifice positioned in its lower part and a liquid discharging system positioned at the orifice. This liquid discharging system is configured to take up a closed state and an open state in which the system allows the liquid to flow towards the outside of the enclosure and includes at least one element that is elastically deformable depending on the pressure inside the enclosure and, depending on its deformation, controls the open or closed state of the liquid discharging system. This solution makes it possible to achieve simple and automatic regulation of the volume of the liquid in the enclosure, without a sensor. An aircraft including at least one such enclosure is also provided.

A fuel cell power system including at least one fuel cell, a ram air system and a cooling circuit in which coolant is intended to circulate for regulating a temperature of the at least one fuel cell. The cooling circuit comprises a ram air heat exchanger in the ram air system and the ram air system comprises a nozzle. The fuel cell power system further comprises a water tank and the fuel cell power system is arranged to flow water from the water tank to the ram air system so as to spray water in ram air via the nozzle. Thus, dimensioning of the ram air system which includes the ram air heat exchanger is reduced.

Disclosed herein is a system comprising: a hydrogen fuel cell; a fuel storage tank; a regulator coupled to the storage tank and the fuel cell; an electronic auto pilot; a rechargeable battery; a power electronics module for delivering power from the fuel cell to the autopilot and the battery; and a heat exchanger coupled to the fuel cell. The fuel cell is characterized by: a minimum continuous power output of no more than 25 W; a maximum continuous power output of no less than 5000 W; a specific power of at least 200 W/kg based on the mass of the fuel cell and any control electronics, cooling components, air delivery components, and water management components; an ability to operate at least 2 psig of hydrogen at an inlet; and an ability to operate at temperatures up to 90° C.