CFD-Based Optimization of Aerodynamic Noise in High-Speed Hair Dryer Flow Channels

The noise generated by high-speed hair dryers significantly affects user experience, with aerodynamic design playing a crucial role in controlling sound emissions. This study investigates the aerodynamic noise characteristics of a commercial high-speed hair dryer through Computational Fluid Dynamics (CFD) analysis. The velocity field, streamline patterns, and vector distribution within the primary flow path and internal cavity were systematically examined. Results indicate that strong interactions between the wake flow generated by the guide vanes and the straight baffle in the rear flow path induce vortex structures near the outlet, which are primarily responsible for high-frequency noise. To address this, the guide vanes and rear flow path geometry were redesigned and optimized for improved acoustic and aerodynamic performance. Underrated operating conditions (28 V, 20,000 rpm), the optimized configuration achieves a noise reduction of more than 2.2 dB while increasing outlet wind speed by over 9%. Moreover, the noise suppression effect becomes more pronounced at lower rotational speeds.