Guidelines for Centrifugal and Axial Fan Installation

Turbulence results in the generation of noise and an increased static pressure drop in the system. Therefore, the airflow at the entrance and exit of a fan
should be as smooth as possible to minimise the generation of turbulence. For this reason, fitting (such as elbows and transitions) should not be placed
too close to a fan. This is illustrated in Figure 58 and Figure 59, which show examples of good and bad air flow conditions for fan installation

Figure 58: Guidelines for Centrifugal Fan Installation

Figure 59: Guidelines for Axial Fan Installation