A.A.Voskoboinick, A.V.Voskoboinick, V.A.Voskoboinick, V.I.Nikishov Pressure fluctuations on the scour surface |
Applied hydromechanics, Vol. 16 (88) ¹ 2, (2014) |
| The results of experimental researches of the field of wall-pressure fluctuations on the scour surface before prismatic pier are presented. The horseshoe vortical structures and wake vortices are generated near-by pier. Two quasistable large-scale horseshoe vortical structures are formed into scour opening before the bluff body. First from them is generated at boundary layer separation from the front edge of scour opening and forms the overhead slope of cavity. The second horseshoe structure of less size is formed at interaction of shear layer above cavity and spilling flow along the frontal surface of prismatic model and forms the bottom slope of cavity. The most depth of scour and intensity of wall-pressure fluctuations takes place wherein a spilling flow interact with the scour soil. In the pressure fluctuation spectra there are the discretes on frequencies of horseshoe vortex rotation. Frequency of horseshoe vortex rotation near-by a prism in (2...3) time higher, than into the overhead streamwise slope deposit of sand in scour opening. |
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KEY WORDS: wall-pressure fluctuations, bridge pier, horseshoe vortex, scour |
| TEXT LANGUAGE: Russian |