Converged statistics for time-resolved measurements in low-speed axial fans using high-frequency response probes

A technique to quantify the convergence of the phase-locked averaging (PLA) processes is applied to a low-speed axial fan, with twin configurations of rotor-stator and stator-rotor arrangements. As a starting point, a concise survey of usual practices employed by other authors in the literature for axial fans and compressors is firstly reviewed, in order to identify fundamental parameters and values typically adopted to guarantee convergence. Finally, typical requirements are given as a function of the variable analyzed, the wake pattern to be described or the global disorder of the flow structures inside axial flow fans.