Experimental investigation of a Kaplan draft tube – Part II: Off-design conditions

Off-design conditions of hydropower turbines are becoming more frequent with the deregulation of electricity markets and the introduction of renewable energy resources. Originally, turbines were not built to operate under such conditions. It is evident that there is a need to develop turbines that can operate under off-design conditions while attaining high efficiency. This may be achieved with computational fluid dynamics (CFD). However, the complexity of Kaplan turbine flows is challenging to treat using CFD. Therefore, detailed experimental investigations are necessary to validate and develop CFD.

[1]  Urban Andersson,et al.  An experimental study of the flow in a sharp-heel Kaplan draft tube , 2009 .

[2]  James Chen-yuan Wu,et al.  Unsteady viscous flow , 1975 .

[3]  W. Glas,et al.  Smoothing and statistical evaluation of laser Doppler velocimetry data of turbulent flows in rotating and reciprocating machinery , 2000 .

[4]  Michel Cervantes,et al.  Effects of boundary conditions and unsteadiness on draft tube flow , 2003 .

[5]  Michel Cervantes,et al.  Phase resolved velocity measurements in a Kaplan draft tube model , 2011 .

[6]  C Deschênes,et al.  Experimental Investigation of Runner Outlet Flow in Axial Turbine with LDV and Stereoscopic PIV , 2008 .

[7]  Magnus Lövgren.  Time dependent pressure phenomena in hydropower applications , 2006 .

[8]  Michel Cervantes,et al.  Experimental investigation of a Kaplan draft tube – Part I: Best efficiency point , 2012 .

[9]  K. Graichen,et al.  Fourier averaging: a phase-averaging method for periodic flow , 2000 .

[10]  Yasutoshi Senoo,et al.  Swirl Flow in Conical Diffusers , 1977 .

[11]  Thomas Vekve,et al.  An experimental investigation of draft tube flow , 2004 .

[12]  Håkan Nilsson,et al.  Large Eddy Simulation of Turbulent Swirling Flow Through a Sudden Expansion , 2006 .

[13]  F. Avellan,et al.  Analysis of the Cavitating Draft Tube Vortex in a Francis Turbine Using Particle Image Velocimetry Measurements in Two-Phase Flow , 2008 .

[14]  D. Telionis.  Unsteady Viscous Flows , 1981 .

[15]  T. O’Doherty,et al.  Vortex breakdown: a review , 2001 .