Emilia SABĂU, Mihai-Andrei DRAGOMIR, Adrian POPESCU, Brînduşa-Aniela RUSU


The design and shape of the draft tube are factors that directly influence energy recovery. A draft tube with an elbow shape for low heads of water flow was studied. The aim was to identify the significance of the draft tube design according to the performance of the Francis turbine. A dimensional calculation was carried out for this purpose, followed by a finite element simulation using Flow Simulation software to verify the velocity of the water flowing through the draft tube. The results of this simulation lead to the fact that the draft tube design is a factor that affect the pressure and velocity at the draft tube’s inlet and outlet.

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