ELECTRIC PROPULSION SYSTEM OF AN AIRCRAFT

A propulsion system includes a system for producing electricity that supplies electricity to at least one electric motor to which is mechanically coupled a propeller situated near a first longitudinal end of a nacelle that houses at least the system for producing electricity and the at least one electric motor. An air circulation channel, which receives a heat exchanger provided to allow the system for producing electricity to be cooled, extends inside the nacelle from a first end of the air circulation channel situated at the first longitudinal end of the nacelle. A part of the air circulation channel that is contiguous with its first end is delimited by an outer surface of cylindrical shape that surrounds the longitudinal axis of the nacelle.