Particle Image Velocimetry Measurements over an Aerodynamically Open Two-Dimensional Cavity

摘要

An experimental study has been undertaken to characterise the low Reynolds number flow over an aerodynamically open two-dimensional cavity of rectangular cross-section. A series of water tunnel experiments have been performed in which the flow field was initially examined using dye flow visualisation, then particle image velocimetry (PIV) was used to obtain quantitative velocity measurements. For a laminar upstream boundary layer, the cavity flow structure has been characterised for a cavity length-to-depth ratio of 5 and Reynolds numbers, based on cavity depth, of 990, 1930, 3780 and 5710. Three different flow regimes were identified over the Reynolds number range tested. The mean PIV flow fields are presented and are found to compare well with the flow visualisation study and existing PIV literature.