Özet:

The numerical investigation of automotive cooling fan module aerodynamic noise based on Computational Fluid Dynamics (CFD) / Computational Aero Acoustics (CAA) hybrid method is taken. Considering the influence of fan shroud, an aerodynamic steady simulation is made at first, and then Large Eddy Simulation (LES) with the Smagorinsky model is applied to capture the unsteady pressure data on fan surface. Based on Lowson formula, a prediction of aerodynamic noise is made by Boundary Element Method (BEM). Finally, the prediction results are compared with the experimental results, which show that the acoustic response is with a strong dipole character. Sound pressure level (SPL) at receive points increased with air flow rate. SPL at outlet was higher than inlet. Tonal noise was the major component of the aerodynamic noise. Broadband noise was relatively lower and distributed evenly. Predicted results is consistent with the experimental results, which validates the numerical prediction method. This method can provide a reference to acoustic optimization.

Anahtar Kelimeler: