چكيده به لاتين
Abstract:
Stilling basins are among the dissipater structures where constructed at downstream of high dams. In this study, effect of inlet flow type into the stilling basin on the hydrodynamic parameters of flow as well as velocity and pressure distributions, pressure fluctuations, vorticities, turbulence intensities and hydrodynamic loads was investigated. To do so, two practical and usual cases include at downstream of a bottom outlet and downstream of a chute spillway were examined and analyzed. To verify the numerical simulations, a scaled physical model was employed. To simulate turbulence phenomenon and free surface, LES and VOF models were used. Results showed that forming hydraulic jumps in the stilling basin caused pressure fluctuations with different distributions along the bottom of basin. Due to difference between strength and place of forming jump in stilling basin model downstream of chute spillway and downstream of bottom outlet, at the first 25% of the stilling basin length, the pressure fluctuations were on average 42.6% more, respectively. Moreover, at final 75% of the stilling basin length due to jet deal to mid-section, pressure fluctuations were 47.3% more, too. The total coefficient of pressure fluctuations in middle of basin’ length in bottom outlet model is 46% greater than the spillway stilling basin, and at the first 25% of the stilling basin length the spillway stilling basin 40% more than the other model. Therefore in the bottom outlet model at final 75% of the stilling basin length needs the thicker slab than the other model and at the first 25% of the stilling basin length the spillway stilling basin needs the thicker slab.
Keywords: Stilling Basin-Pressure Fluctuation- FLOW-3D-Spillway- Bottom Outlet
