AERODYNAMICS AND AEROACOUSTICS OF AIRFLOW OVER A HUMAN HEAD

Airflow should be affected by ear, nose, etc, and aerodynamic sound could be brought when the human head and the airflow occurs at a relative speed movement. Because the drag force of the head is large, in cycling competitions and other high-speed sport the diversion hats should be worn. After the speed of airflow reaches to a certain speed, due to the strong airflow interference, the aerodynamic noise could be brought and it could greatly impact on the athletes to make action decisions. In this paper, computational fluid dynamics (CFD) method is used for solving the aerodynamic behavior of a human head under different air velocities, and the pressure on head surface and the airflow around the head are calculated. Then, the above-mentioned conditions of different aerodynamic sound are solved by the finite element/infinite element method (FEM/IFEM), the points in the canal entrance of the two ears are picked up for collecting the SPL spectral curves, and the sound distribution of the horizontal plane and the median plane are drawn. Previous studies showed that the aerodynamic noise brought by head spoiler is obvious at low frequencies, because the influence of the head, if the airflow speed is greater than a certain value, the aerodynamic noise could not only increase, but also should be substantially reduced. The results are useful for athlete diversion cap design and spatial hearing research in which the influence of the airflow should be considered.