Subsonic Wind Tunnel Facility for PIV and blade Flutter Experiments

摘要

The paper presents an overivew, components and basic performance of a subsonic wind tunnel facility for particle image velocimetry (PIV) measurement and three-dimensional blade flutter experiment. The PIV system comprises a double-pulsed Nd: YAG laser, a CCD camera and a seeding apparatus whcih consists of a fog generator, an aerosol seeder and a cyclone. The fog generator is useful for a qualitative visualization in low-speed flows. The aerosol seeder can be utilized as a continuously agitated fluidized-bed solid particle generator for a quantitative PIV visulaization in high-speed flows. The cyclone is particularly successful in removing the large particle agglomerates typically produced by the solid particle resuspension process that takes place in the aerosol generator. Using the PIV system, customized image acquisition is used to quickly process the data, and the two-dimensional velocity field is rapidly provided. A uniform flow velocity of 75.9/s is presented as the example of the PIV measurement. The flutter frequency and the critical velocity are estimated 130 Hz and 114 m/s respectively from the flutter experiment of the three-dimensional flat blade in subsonic flows.