Numerical Study on the Flow Characteristics of Low Head Small Hydraulic Turbine

Abstract:

A small hydraulic turbine more still remains to improve the mechanical performance because it does not come fully similarity as compared with the large-scale hydraulic turbine. Many studies on the small hydraulic turbine focused on the increase of performance. In this study, the characteristics of axial propeller turbine which is appropriate equipment for low head conditions and high flow rates were numerically investigated using the commercial code, ANSYS CFX. A parametric study was carried out with two different geometrical parameters, such as blade number and tip clearance between casing and blade. Results showed that the hydraulic loss was increased and the efficiency of small hydraulic turbine was decreased because of increasing tip clearances, which lead to the increase of absolute velocity at the exit of the runner blade.

• Periodical: Advanced Materials Research (Volumes 732-733)
• Pages: 436-442
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.732-733.436
• Online since: August 2013
• Authors: Sun Seok Byeon, Jin Hyo Boo, Chong Yun Park, Sung Soo Kim, Youn Jea Kim*
• Keywords: Blade Number, Free Vortex Theory, Head, Propeller Hydro Turbine, Shaft Power

References

[1] Alexander, K. V., Giddens E. P., Fuller A. M., 2008, Optimum penstocks for low head microhydro schemes, J. of Renewable Energy, Vol. 33, pp.1379-1391.

DOI: 10.1016/j.renene.2007.01.009

[2] Alexander, K.V. Giddens, E. P., Fuller, A.M., 2009, Axial-flow turbines for low head micro hydro systems. J. of Renewable Energy, Vol. 34, pp.35-47

DOI: 10.1016/j.renene.2008.03.017

[3] Singh, P. and Nestmann, F., 2011, Experimental investigation of the influence of blade height and blade number on the performance of low head axial flow turbines, J. of Renewable Energy, Vol. 36, pp.272-281.

DOI: 10.1016/j.renene.2010.06.033

[4] Singh, P. and Nestmann, F., 2010, Exit blade geometry and part-load performance of small axial flow propeller turbine: An experimental investigation, J. of Renewable Energy, Vol. 34, pp.798-811.

DOI: 10.1016/j.expthermflusci.2010.01.009

[5] Singh, P. and Nestmann, F., 2009, Experimental optimization of a free vortex propeller runner for micro hydro application, J. of Renewable Energy, Vol. 33, pp.991-1002.

DOI: 10.1016/j.expthermflusci.2009.04.007

[6] Ferro, L. M. C., Gato, L. M. C., and Falcao, A. F. O., 2011, Design of the rotor blades of a mini hydraulic bulb-turbine, Renewable Energy, Vol. 36, pp.2395-2403.

DOI: 10.1016/j.renene.2011.01.037

[7] Ramos, H. M., Simăo M., and Kenov, K. N., 2011, Low-head energy conversion: A conceptual design and laboratory investigation of a microtubular hydro propeller, International Scholarly Research Network ISRN Mechanical Engineering, ID: 846206.

DOI: 10.5402/2012/846206

[8] Dixon, S. L., 2005, Fluid Mechanics, Thermodynamics of Turbomachinery, Elsevier, Oxford, UK, Chapters 2, 6 and 9.

[9] Gorla, R. S. R. and Khan, A. A., 2003, Turbomachinery Design and Theory, Marcel Dekker, New York, Chapters 1 and 3.

[10] Wilcox, D. C., 1986, Multiscale model for turbulent flows, AIAA 24th Aerospace Sciences Meeting, American Institute of Aeronautics and Astronautics, pp.1598-1605.

DOI: 10.2514/6.1986-29

[11] Menter, F. R., 1994, Two-equation eddy-viscosity turbulence models for engineering applications, AIAA J., Vol. 32(8), pp.1598-1605.

DOI: 10.2514/3.12149

[12] ANSYS CFX ver.13 User's Guide, 2011, ANSYS Inc.