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Performance Characteristics in Draft Tube - A Review 

Arpit Pawar*

Journal of Advanced Mechanical Sciences. 2022 Aug 29; 1(3): 88- 92

ABSTRACT


            The draft tube elbow was modelled using the fundamental geometry of GAMM Francis turbine. Its purpose was to design a draft tube with improved hydrodynamic performance This was accomplished by integrating unfasten resource and commercialized technologies to optimize and update the shape and CFD grid, and analyzing pressure retrieval and mechanical power wounded next to draft tube intend through Computational Fluid Dynamics (CFD). A technique was used to evaluate the functioning of an elbow draft tube. According to CFD, an 18.8° inclined angle has been the best way in blocking the production of physically powerful swirl stream and resulting in reducing the amplitude of pressure fluctuation. The blade passing frequency dominates the draft tube entrance, influencing local pressure recovery; however, the low-frequency core instability quickly diffuses and taps it. 

Keywords:

Processing vortex rope, Solidity, Draft tube, CFD, Francis Turbine.

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