Hydro Nepal: Journal of Water, Energy and Environment, 2012
Draft tube is an important component of the hydraulic reaction turbine and affects the overall pe... more Draft tube is an important component of the hydraulic reaction turbine and affects the overall performance of turbine to a large extent. The flow inside the draft tube is complex because of the whirling flow coming out of runner and its diffusion along the draft tube. The kinetic energy coming out of runner is recovered in draft tube and part of recovery meets the losses. In the present work, the computational fluid dynamics (CFD) has been used for flow simulation in complete mixed flow Francis turbine for performance analysis for energy recovery, losses and flow pattern in an elbow draft tube used in Francis turbine at different operating conditions. The overall performance of the turbine at some typical operating regimes is validated with the experimental results and found to be in close comparison.DOI: http://dx.doi.org/10.3126/hn.v10i0.7103 Hydro Nepal Vol.10 January 2012 48-52
Hydro Nepal: Journal of Water, Energy and Environment, 2011
The testing of physical turbine models is costly, time consuming and subject to limitations of la... more The testing of physical turbine models is costly, time consuming and subject to limitations of laboratory setup to meet International Electro technical Commission (IEC) standards. Computational fluid dynamics (CFD) has emerged as a powerful tool for funding numerical solutions of wide range of flow equations whose analytical solutions are not feasible. CFD also minimizes the requirement of model testing. The present work deals with simulation of 3D flow in mixed flow (Francis) turbine passage; i.e., stay vane, guide vane, runner and draft tube using ANSYS CFX 10 software for study of flow pattern within turbine space and computation of various losses and efficiency at different operating regimes. The computed values and variation of performance parameters are found to bear close comparison with experimental results.Key words: Hydraulic turbine; Performance; Computational fluid dynamics; Efficiency; LossesDOI: 10.3126/hn.v7i0.4239Hydro Nepal Journal of Water, Energy and EnvironmentVo...
The reaction turbines have application in very wide range hydro power projects. The turbines are ... more The reaction turbines have application in very wide range hydro power projects. The turbines are the most important components of any hydro power plant. Its cost varies 15-35% of the total cost of hydropower project. Thus the cost effective design of the turbine is of utmost importance. It is very crucial to understand the flow behavior of the turbine under various operating conditions. The model testing of turbines give overall performance of turbines based on global parameters. This approach is very costly and time consuming. But the detailed analysis of the performance of turbine is important under off-design and overloading conditions. Now-a-days computational fluid dynamics compliments experimental and theoretical approach by providing an alternate cost effective means of simulating real flow as it is much cheaper than experimental testing. In the present paper, the numerical flow simulation in reaction turbines ie, the axial and mixed flow turbines has been carried out to stud...
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