Energy Dissipation due to Compound Stilling Basin

It’s much common for the outgoing flow from the separated stilling basin to laterally diffuse and then form a large-scale reverse flow due to suddenly expanding flow section outside the stilling basin. Aimed at this problem, this paper proposes to remove the conventional splitter wall to form a compound stilling basin. Based on a RNG k-ε turbulent model, numerical simulation is conducted to investigate the corresponding influence upon the downstream flow field. Compared to the separated stilling basin, the running inflow inside the compound stilling basin would greatly diffuse and then transform into a three dimensional hydraulic jump with high energy dissipation due to an enlarged inflow section by the removed splitter wall, especially for the condition of bottom outlet running alone. The average velocity and average pressure inside the compound stilling basin in bottom outlet running alone condition decrease by 35%~49%, 7%~24%, respectively. Moreover, the maximum turbulent kinetic energy and average velocity among the outgoing flow decrease by 70%, 30%, respectively. The velocity gradients among the outgoing flow decreases as low as zero with the phenomenon of oblique movements outside the stilling basin been eliminated.