Gas transfer pumps - Kinetic pumps

In the article on positive displacement pumps published in Techniques de l'Ingénieur, it was noted that the principle behind these pumps is purely compression by volume variation. This is not the only physical principle that enables gases or vapors to be evacuated or transferred from an enclosure to a vacuum.

The second principle involves changing the velocity vector of the molecules in order to drive them into another medium. This change can be achieved in a number of mechanical ways, by imparting velocity components to the molecules to make them move wherever we want. These means differ from one another, from the macroscopic (turbine blades...) to the microscopic (impact of fluid molecules on the molecules to be pumped...). This gives us the different types of pump:

• fluid-powered pumps (ejector, etc.) ;

• mechanically driven pumps (turbomolecular pump, axial turbine and side channel).

For further information on vacuum generation and positive displacement pumps, please refer to the following articles and of this treatise [1][4] .