PIV Study on Grid-Generated Turbulence in a Free Surface Flow
نویسندگان
چکیده
To investigate the feature of turbulence developing behind filter device in a current flow, flow fields at intermediate downstream distance an immersed grid open water channel are recorded using two-dimensional (2D) Particle Image Velocimetry (PIV) system. The measurements on series vertical and horizontal sections conducted to reveal stream-wise evolution depth diversity free surface flow. Unlike previous experiments by Laser Doppler (LDV) Hot-Wire Anemometry (HWA), integral scales space-time correlations estimated without Taylor hypothesis this paper. distributions mean velocity, intensity scale show transition behavior grid-generated from perturbations fully merged homogenous turbulence. velocity become more uniform with increasing distance. While spatial divergence becomes pronounced as structures develop downstream. parameters characteristics direction influenced outer part boundary layer (TBL) bottom. applicability newly proposed two-order elliptic approximation model for decaying is verified different positions. calculated convection large-scale motion sweep small-scale based bring new insight into dynamic pattern type
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ژورنال
عنوان ژورنال: Water
سال: 2021
ISSN: ['2073-4441']
DOI: https://doi.org/10.3390/w13070909