Angular flow of two bridge models.
Keywords:
group bridge pier, angular flow, velocity field, coherent vortex structuresAbstract
The features of generation of the large-scale vortex structures, which form the horseshoe vortex system, are investigated experimentally in the wake flow around two bridge models. Scales and locations of the vortex structures, as well as kinematical and dynamical characteristics of the velocity fields are determined near-the model of three-row pile grillage, which is located behind the prismatic pier in the angular and axisymmetric flow. Visual study allows one to find the areas of forming of the local and global scours in front of the bridge piers, and study their evolution and areas of maximal wall shear stresses. It is shown that the values of velocities near the three-row pile grillage increased in the angular flow around of models compared to their axisymmetric flow values.References
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