Abstract: A target volume evacuation system includes a turbo compressor and a vacuum pump, the system being operable in a first configuration to reduce the target volume pressure from ambient to a first intermediate pressure, e.g. between 200 mbar and 50 mbar, and in a second configuration to further reduce the pressure from a second intermediate pressure, e.g. 10 mBar, to a target partial vacuum, e.g. between 0.1 and 1 mbar. The turbo compressor can be driven electrically or by fuel combustion, and can be a conventional or modified turbojet engine. A plurality of turbo compressors can be transitioned from parallel to series operation. The pressure can be reduced from the first to the second intermediate pressure by venting the target volume to a boom-tank volume and/or by configuring the turbo compressor system to provide backing to the vacuum pumping system. The invention is applicable to a hyperloop transport system.

Abstract: A method for evacuating a chamber employs a pump arrangement composed of a booster pump and of a downstream forepump is connected to the chamber. The booster pump is accelerated, gas from the chamber is introduced into the booster pump, such that from the booster pump there is temporarily extracted an excess power which exceeds the power provided by the drive of the booster pump. The gas is discharged through a bypass valve while the outlet pressure of the booster pump lies above a predefined threshold value, and the gas is directed to the forepump when the outlet pressure of the booster pump has fallen below the threshold value. The gas supplied by the booster pump is compressed by means of the forepump.

Abstract: A target volume evacuation system includes a turbo compressor and a vacuum pump, the system being operable in a first configuration to reduce the target volume pressure from ambient to a first intermediate pressure, e.g. between 200 mbar and 50 mbar, and in a second configuration to further reduce the pressure from a second intermediate pressure, e.g. 10 mBar, to a target partial vacuum, e.g. between 0.1 and 1 mbar. The turbo compressor can be driven electrically or by fuel combustion, and can be a conventional or modified turbojet engine. A plurality of turbo compressors can be transitioned from parallel to series operation. The pressure can be reduced from the first to the second intermediate pressure by venting the target volume to a boom-tank volume and/or by configuring the turbo compressor system to provide backing to the vacuum pumping system. The invention is applicable to a hyperloop transport system.

Abstract: A method for evacuating a chamber employs a pump arrangement composed of a booster pump and of a downstream forepump is connected to the chamber. The booster pump is accelerated, gas from the chamber is introduced into the booster pump, such that from the booster pump there is temporarily extracted an excess power which exceeds the power provided by the drive of the booster pump. The gas is discharged through a bypass valve while the outlet pressure of the booster pump lies above a predefined threshold value, and the gas is directed to the forepump when the outlet pressure of the booster pump has fallen below the threshold value. The gas supplied by the booster pump is compressed by means of the forepump.