Comparison between hydraulic and structural based anti-vortex methods at intakes

. Surface vortices are the main reason of flow instability and entraining air and debris into the intakes. Using structural based anti-vortex facilities is a common method for dissipating vortices over the intakes. In the present experimental study, performance of a new hydraulic based anti-vortex method is compared with available structural based anti-vortex methods over the horizontal intakes. In the new approach dynamically high-risk surface vortices are eliminated by imposing a hydraulic jet at the formed vortex zone over the intake. The injected jet acts as a point source of external momentum in order to change the hydrodynamic condition of the formed vortex flow. Results show that the investigated hydraulic based anti-vortex device is more flexible and more hydraulically efficient than the structural based anti-vortex methods, especially when the intake Froude number is higher than 1.3.