Abstract
When measuring turbine prototype flow, a number of modes with different flow rates and cavitating vortex rope settings have been measured. The turbulent flow in the draft tube of diameter 240 mm reaches the Reynolds number of 105. The vortex and highly swirling flow is developed in the draft tube. The usage of kHz-order frame rates was necessary to resolve the velocity field. The investigated area in the mixing vessel was examined by the stereoscopic time-resolved PIV technique. Further mode evaluation allows comparison of cross-sectional velocities in the vector map. The Proper orthogonal decomposition analysis was applied on 3D vector maps, those including u, v, w velocity compounds. In the selected regimes – operating points with volume flow rate 97 l/sec and 114 l/sec, the greatest risk of transition to cavitation mode was identified, so they were studied in detail.
Highlights
The vortex and highly swirling flow is developed in the draft tube
The Proper orthogonal decomposition analysis was applied on 3D vector maps, those including u, v, w velocity compounds
In the selected regimes – operating points with volume flow rate 97 l/sec and 114 l/sec, the greatest risk of transition to cavitation mode was identified, so they were studied in detail
Summary
The development of energy storage re-sources is a response to weather fluctuations and growth of green power plants (solar and wind power). There raises an urgent need for energy storage and its use depending on the immediate increase. It is very closely connected with ensuring the safety and stability of the distribution system. The most effective functions are assured by pumped-storage hydroelectric power plants (PVE). The usage of conventional reverse turbines in off-optimal modes brings an unstable closed flow causing the vibration pulsation of the turbocharger. It forces the limitation of the working scope
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
