Abstract: An on board inert gas generation system for an aircraft receives air from a relatively low pressure source such as low pressure engine bleed air or ram air and passes it to a positive displacement compressor to increase the pressure thereof to be suitable for supply to an air separation module. The speed of the positive displacement compressor may be adjusted across a wide range in order to provide efficient operation in cruise and descent phases of aircraft flight. The operating speed of the compressor and/or the flow rate from the ASM to the space to be inerted may be controlled in accordance with at least one of the gas composition in the space to be inerted, the flight condition, and the ullage volume.

Abstract: An on board inert gas generation system for an aircraft receives air from a relatively low pressure source such as low pressure engine bleed air or ram air and passes it to a positive displacement compressor to increase the pressure thereof to be suitable for supply to an air separation module. The positive displacement compressor comprises a high pressure ratio single stage supercharger with internal cooling.