Periodic Flow in a Wind Tunnel Produced by Rotating Shutters

摘要: The periodic flow obtained in a wind tunnel test section by means of an upstream pulsator is investigated. The turbulence level in this section is quite small and the direction of the periodic velocity is that of the mean velocity. The measurement of the velocity skewness and flatness factors indicates that true sinusoidal pulsation is achieved only for the resonance frequency which depends little on the length of the test section.