Experimental investigation of the 3D unsteady flow field downstream of axial fans

Experimental study of blade thickness effects on the overall and local performances of a Controlled Vortex Designed axial-flow fan

“…5a. The flow downstream of the fan already has a very important radial component as noticed by Kergoulay et al [2]. The discharging flows for the two fans at their respective nominal flow-rate (Fig.…”

“…The blades are stacked on the trailing edge. The blades are finally swept forward in order to benefit from lower tonal noise as suggested by several studies [1][2][3][4]. The forward sweep may also increase or decrease the overall performance, depending on the blade loading distribution, as reported in Refs.…”

“…The method to get the three velocity components is the same as described in Refs. [2,4] and is based on two measurements at different angular positions of the probe.…”

“…That corresponds to roughly 150 revolutions of the fans and to approximately 3600 samples per revolution. The rotation rates have been measured with an encoder, synchronized to the CTA data acquisition, in order to perform analysis of phase-averaged signals [2]. This point has been chosen as close as possible to the fans blades, and such that the three components of the velocity are close for both fans, as can be seen in Fig.…”

“…An example of one parameter that dramatically modifies the performances is for instance the blade sweep [1][2][3][4]. A second parameter that should affect the performances is the blade thickness.…”