In this study, flow characteristics such as flowrate, water surfaces, crest pressures on the ogee-spillway, and vertical distributions of velocity and pressure in consideration of model scale and surface roughness effects are investigated in detail by using the commercial CFD model, FLOW-3D, which is widely verified and used in the field of spillway flow analysis. Numerical errors in the discharge flowrate, water surfaces, and crest pressures due to the surface roughness are insignificant if we just use a general roughnessheight of construction materials, and the scale effects of the model are in an acceptable error range if the length scale ratio is less than 100 or 200. The roughness and scale effects are more severe belowhm, where the maximum velocity occurs in perpendicular coordinate to the weir crest. The velocity of the prototype is larger than that of the scaled model below but the phenomena are contrary abov ehm. Maximum velocity at any section slightly decreases as the surface roughness and the length scale ratio increase. The vertical location where maximum velocity occurs is located on a lower position as the upstream water head increases and the location almost linearly increases with the distance from the front of the spillway.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Analysis of flow structure over ogee-spillway in consideration of scale and roughness effects by using CFD model


    Additional title:

    KSCE J Civ Eng


    Contributors:

    Published in:

    Publication date :

    2005-03-01


    Size :

    9 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English






    Effect of low tailwater during drought on scour conditions downstream of an ogee spillway

    Hong, Seung Ho / Kim, S. J. / Sturm, Terry W. et al. | HENRY – Federal Waterways Engineering and Research Institute (BAW) | 2010

    Free access


    An application of the Ogee tip

    Vogel, J. M. | NTRS | 1975