Elmo Rietschle

The air flow depends on the position and direction of the rotors. The typical installation provides a constant air flow, and that the rotational direction is dependent on the “Roots” blower design. As a side note, the Roots blower design is enduring and durable. The rotary positive air blower was designed in the 1850s and patented in 1860 by brothers Francis and Philander Roots and the Roots name has remained as the description of the design.

The basic principle is as follows: the process starts with air flowing from the inlet port into the element chamber. The timed rotation of the rotors against the wall of the chamber creates so-called “air flow direction”. There is still atmospheric pressure in these chambers. 

As soon as the first lobe passes the opening to the pressure side, the system pressure is adjusted. This is called isochoric compression. The rotors seal each other off to the inside, which prevents a change of pressure.