• 제목/요약/키워드: Strauhal Number

검색결과 2건 처리시간 0.015초

지면에 근접한 정사각주 주변의 유동장 연구 (Investigation on the Flowfield Around a Square Cylinder near a Wall)

  • 황재호;박영회;김태윤;이동호
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집E
    • /
    • pp.754-759
    • /
    • 2001
  • This paper presents unsteady computational investigations and wind tunnel tests on the flow field around a square cylinder with a gap between the body and the ground plane. Two-dimensional unsteady, incompressible Navier-Stokes codes are developed for the computation of the viscous turbulent flows. By computing the flow around a square cylinder without ground effect, three two-equation turbulence models are evaluated and the developed code is validated. The results show a good agreement with experimental values and other computational results. Critical gap height at which the formation of Karman vortex streets is interrupted, is demonstrated and another transition regime is pointed out

  • PDF

INVESTIGATION OF THE MEANDER PLANFORM DEVELOPMENT IN A LABORATORY CHANNEL

  • Yilmaz, L.;Singh, Vijay P.;Mishra, S.K.;Adrian, D.D.;Sansalone, J.J.
    • Water Engineering Research
    • /
    • 제3권3호
    • /
    • pp.177-193
    • /
    • 2002
  • Experiments were conducted in an initially straight laboratory alluvial channel to investigate channel meandering characteristics. The experimental observations revealed an empirical relation between three types of tortuosity ratios used for describing meandering characteristics. Furthermore, the Strauhal number was found to be higher for bed material with greater resistance to erosion than with lower resistance to erosion. The meandering characteristics were also investigated using the concept of buckling employed in solid mechanics and the concept of siphoning of fluid mechanics. The buckling of flow, attributable to the flow nonuniformity across the channel cross-section, was found to follow the same pattern as did meandering observed experimentally. The processes of expansion of meanders and cut-off can be explained using the concept of siphoning. The results of expanding meander planforms observed in four experimental tests supported the viability of these concepts.

  • PDF