Method and sysem for humidifying an air supply of a fuel cell for aircraft

A method for managing humidification of air in an air supply of a fuel cell for an aircraft, an air supply circuit of the fuel cell including an injection line, an intermediate line passing through a cathode, and an evacuation line, the air flowing in a predefined direction in the air supply circuit, passing successively through the injection line, the intermediate line and the evacuation line,

• the method including steps of:
• recovering the air, referred to as “recycled air”, from the fuel cell, in the evacuation line,
• injecting into the injection line the recovered recycled air so as to mix the recycled air with ambient air,
• increasing a ratio of recycled air relative to ambient air in the injection line when a voltage supplied by the fuel cell reaches or rises above a maximum authorized voltage limit, and
• reducing the ratio of recycled air relative to ambient air in the injection line when the voltage supplied by the fuel cell falls below a maximum authorized voltage limit.

An air supply circuit of a fuel cell for an aircraft, the supply circuit being configured to humidify the air supplying the fuel cell, the air supply circuit including:

• an injection line,
• an intermediate line passing through a cathode of the fuel cell, and an evacuation line,
• the air flowing in a predefined direction in the supply circuit, passing successively through the injection line, the intermediate line and the evacuation line,
• the air supply circuit additionally including a line, referred to as “recirculation line” including:
• a first end connected to the evacuation line so as to recover the recycled air, coming from the fuel cell, and
• a second end connected to the injection line, so as to inject, into the injection line, the recovered recycled air and mix the recycled air with ambient air,
• the air supply circuit being configured to increase a ratio of recycled air relative to ambient air in the injection line when a voltage supplied by the fuel cell reaches or rises above a maximum authorized voltage limit, and
• wherein the supply circuit is configured to reduce a ratio of recycled air relative to ambient air in the injection line when the voltage supplied by the fuel cell falls below the maximum authorized voltage limit.