How to optimize axial fans in terms of noise? 

Axial fans can be optimized in terms of noise through various methods. One approach is to modify the blade airfoil and increase the chord length, which reduces the pressure gradient at the blade tip and improves aerodynamic noise . Another method involves optimizing the structure of the inlet guide vanes (IGVs) in large axial flow fans. This can be achieved through numerical simulation analysis and the use of multi-objective optimization design methods. By employing parameterization methods and the Sobol´ method for sensitivity analysis, the IGVs can be optimized to increase total pressure and decrease noise . Additionally, the tonal noise of axial fans can be reduced through parametric optimization, considering variables such as the number of blades and the angles between blades . Furthermore, a reduced-order model (ROM) based on the blade element theory, lifting line theory, and Amiet's trailing-edge noise model can be used to predict rotor self-noise for axial cooling fans. This ROM provides accurate predictions and significantly reduces computational costs, making it suitable for low-noise fan design and optimization .

Towards Quieter Air-Cooling Systems: Rotor Self-Noise Prediction for Axial Cooling Fans

The paper proposes a reduced-order model (ROM) based on blade element theory, lifting line theory, and Amiet's trailing-edge noise model to accurately predict rotor self-noise for axial cooling fans. This ROM can be used for low-noise fan design and optimization.

Cooling System Axial Fan Design Calculation and Optimization in Terms of Tonal Noise

The paper discusses the optimization of axial fans in terms of tonal noise reduction through parametric optimization of the number of blades and angles between blades.

IGV Optimization for a Large Axial Flow Fan Based on MRGP Model and Sobol’ Method

The paper provides a novel optimization method for large axial flow fans, which includes parameterization methods and the use of the multiple-response Gaussian process (MRGP) approximate model and the Sobol´ method for sensitivity analysis. The optimized fan in the study showed a decrease in noise by 7.2 dB.

Optimization Design for Aerodynamic Noise Reduction of Train Air-Conditioning Axial Fan

The paper proposes three optimization schemes for reducing the aerodynamic noise of axial flow fans, including modifying the blade airfoil and increasing the chord length.

Optimization Design for Aerodynamic Noise Reduction of Train Air-Conditioning Axial Fan

The paper proposes three optimization schemes for reducing the aerodynamic noise of axial flow fans, including modifying the blade airfoil and increasing the chord length.