Towards a low-noise axial fan for automotive applications

The demand for quieter vehicles is pushing manufacturers of components for the automotive industry to seek for solutions to reduce the overall noise emissions. The cooling fan makes no exception: the aerodynamic interaction of the blades with the incoming flow generates turbulence and pressure fluctuations which ultimately translate into noise generation. A variety of expedients have been introduced to limit the produced noise, but no univocal solution has been found. In modern research, Computational Fluid Dynamics (CFD) has been successfully applied to blades and fans for both the flow and acoustic field derivation. By including the acoustic field, researchers have been able to predict the effect of changes in the blade geometry on the overall sound emission. This work reports a conjugate numerical-experimental study of a reference profile in different flow conditions, in order to validate the CFD acoustic prediction and to lay the basis for improved candidates able to lower the fan-generated noise.