Author(s): G. Christodoulou; T. Papathanassiadis
Linked Author(s): George Christodoulou
Keywords: Vortex drop; Physical model; Spiral flow; Energy dissipators; Stormwater drainage; Drop manholes
Abstract: An experimental study of a vortex drop structure in the Athens area was carried out on a physical model at a scale 1: 10. The incoming flow was supercritical, the design discharge 15 m3/s and the elevation difference between the inlet and the bottom outlet about 35 m. The preliminary design of the spiral intake, the dropshaft and the bottom chamber followed Hager (1999). Experimental measurements included the water elevation along the outer wall of the spiral, pressure distributions on the outer wall of the spiral and along the dropshaft and water levels in the bottom chamber. It was found that the max water elevation expression on the spiral given in the literature agreed well with the measured values, considering the different roughness of the model. The diameter of the dropshaft proved adequate, whereas the bottom chamber dimensions could be made appreciably smaller than originally suggested.
Year: 2005