Colloquium: Tjeu Gehlen (FPT)

With the increasing demand on electric vehicles to reduce the environmental impact of the transport section, noise levels have decreased in general. However, noises that were previously masked by loud engines are now apparent, and cooling fan noise is an example of this. During charging, large cooling demands are needed with no inflow from driving present. Flow obstruction have shown the potential to reduce the tonal noise (caused by periodic blade force fluctuations), in fans with equal blade spacing. This research aims to investigate if they can also be applied to current industry fan modules with upstream radiators and unequally spaced blades. It was found that it is indeed possible to significantly reduce a desired tone, and also control more than one tone using a superposition of obstructions. However, since there are numerous loud tones in unequally spaced fans,  the reduction in overall noise is limited.

Supervisor: Daniele Ragni