Ejectors and Thermocompressors, like the Liquid Jet Gas Eductors can be used to create vacuums. These are known as Vacuum Ejectors or sometimes, incorrectly, Vacuum Eductors.
Unlike a Liquid Eductor, Vacuum Ejectors and Thermocompressors having a gaseous motive can be installed in series to create even greater vacuums as well as being able to recover the suction gas and compress this to even higher pressures. An ejector which recovers low pressure gases is known as a Booster Ejector and is commonly used in waste gas recovery applications.
Thermocompressors & Ejectors can be designed with a spindle and actuator which creates a variable area motive nozzle which allows optimal operation across a range of motive conditions.