1. Fundamental concepts

1.1 Classification

In the field of compression turbomachinery, the following two types of classification can be found.

• Depending on use, we have :

  • fans: low compression ratio (less than 1.20 in air) and low fluid velocity in the machine flow;

  • blowers: characterized by the marked appearance of compressibility with higher compression ratios (between 1.20 and 2) and higher speeds;

  • compressors: high compression ratio (greater than 2) may require the use of several compression stages connected in series.

• Depending on the geometric shape (with two main shapes),...