کاهش نویز آیرودینامیکی دمنده با الهام از الگوی زیگزاگی بال جغد: یک مطالعه تجربی

This study experimentally investigates the effect of a serrated pattern, biomimetically inspired by the trailing edge of an owl's wing, on reducing the aerodynamic noise of a fan. The tests were conducted in an acoustic chamber compliant with the ISO-3745 standard, using four calibrated microphones positioned one meter from the rotor. The baseline overall average sound pressure level (OASPL) of the fan (without modifications) was measured at 64.13 dB. Subsequently, the serrated pattern was installed on the leading edge and trailing edge of the blades. Results indicated that installing the add-on on the leading edge led to a 1.61 dB (2.5%) reduction in OASPL, with a maximum individual reduction of 14 dB occurring at 2 kHz—within the range of maximum human hearing sensitivity. Installation on the trailing edge resulted in a 2.58 dB (3.8%) reduction in OASPL, with a peak reduction of approximately 15 dB at 150 Hz. This research confirms the effectiveness of the owl-inspired serrated pattern as a passive biomimetic strategy for mitigating aerodynamic noise in fans, particularly within frequency ranges critical to human perception. Geometric optimization of this pattern and further investigation into the associated flow mechanisms present a promising direction for future research.