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In an assessment of PIV measurement accuracy under practical experimental circumstances, grid-generated turbulence in its early decay (xiM =13.6-15.2, ReA z 25) has been studied. Since a realtime processor was used, it was practical to acquire a statistically significant sample size of 3000 vector maps so that accurate turbulence statistics could be calculated. Results include moments of velocity components and spatial structures in terms of auto-correlations, turbulence scales and spectra. Data fall within limits of standard error estimates. This study demonstrates the need for large sample sizes, particularly for higher order statistics. Displacement vector [L] dpiXe! Pitch of pixels on CCD chip [L] d,truct Diameter of smallest resolved velocity-structure [L] f Longitudinal correlation function g Lateral correlation function g' Theoretical correlation function G k ID power density spectrum [VIP] k Turbulent kinetic energy [VIP] k' Harmonic number M Mesh spacing [mm] N Number of samples N, Number of vector maps N« Side of interrogation area [pixels] N, Number of vectors in x-direction N, Number of vectors in y-direction ReM Reynolds number based on mesh spacing, MUiv ReA Reynolds number based on the Taylor microscale, A,

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