Theoretical Approach to the Performance Analysis of a Low-Specific Speed Pump as Turbine Based on Hydraulic Losses
Main Article Content
Abstract
This paper focuses on building a theoretical method, based on the calculation of hydraulic losses to predict the energy performance of a Low-specific speed Pump as Turbine (PaT) quickly and accurately that supported for the PaT’s impeller design. The Euler equation is built with the analysis of hydraulic loss calculation and flow phenomena passing on the machine. The trust of this approach is validated by comparing with the available experimental data. The results show that the theoretical energy curves of the PaT are in a good agreement with the tendency of the experimental results in both pump and turbine modes in vicinity of design point. Thereby, we estimated the head loss distributions in the flow system of PaT, including: the total of the head loss, the impeller loss, the disk friction and spiral casing losses. From these results, to improve and harmonize the efficiency of reversible impeller in both pump and turbine modes, the designer is recommended to decrease the diameter D₂ and increase the impeller widths b₁, b₂ for improvement.
Keywords
Pump as turbine, reversible impeller, hydraulic losses, turbomachine, storage hydropower
Article Details
References
[1] S. V. Jain and R. N. Patel, Investigations on pump running in turbine mode: A review of the state-of-the-art, Renewable and Sustainable Energy Reviews, vol. 30, pp. 850-852, 2013.
[2] S. Derakhshan and A. Nourbakhsh, Experimental study of characteristic curves of centrifugal pumps working as turbines in different specific speeds, Experimental thermal and fluid science, vol. 32, pp. 801-806, 2008.
[3] S. V. Jain and R. N. Patel, Investigations on pump running in turbine mode: A review of the state-of-the-art, Renewable and Sustainable Energy Reviews, vol. 30, pp. 850-852, 2013.
[4] S. Derakhshan and A. Nourbakhsh, Experimental study of characteristic curves of centrifugal pumps working as turbines in different specific speeds, Experimental thermal and fluid science, vol. 32, pp. 801-806, 2008.
[5] H. Bing, L. Tan, and L. Lu, Prediction method of impeller performance and analysis of loss mechanism for mixed-flow pump, Science China Technological Sciences, vol. 55, no. 7, pp. 1989-1994, 2012.
[6] F. J. Gülich, Pump hydraulics and physical concepts, in Centrifugal Pumps, Second edition, Springer Heidelberg Dordrecht London New York, ISBN 978-3-642-12823-3, 2010, pp. 100-140.
[7] J. M. Chapallaz, Manual on Pumps Used as Turbines, Germany: Lengericher Handelsdruckerei, Lengerich, ISBN 3-528-02069-5, 1992.
[8] S.-S. Yang, F.-Y. Kong, W.-M. Jiang, and W.-M. Jiang, Effects of impeller trimming influencing pump as turbine, Computers & Fluids, vol. 67, pp. 72-78, 2012.
[9] G. Shi, X. Liu, J. Yang, S. Miao, and J. Li, Theoretical research of hydraulic turbine performance based on slip factor within centripetal impeller, Advances in Mechanical Engineering, pp. 1-12, 2015.
[10] B. Djebedjian, Theoretical model to predict the performance of centrifugal pump equipped with splitter blades, MEJ, vol. 34, no. 2, pp. 50-70, 2009.
[11] I. Pădurean, Study of hydraulic losses in the francis turbines, The 6th international conference on hydraulic machinery and hydrodynamics, Timișoara, 2004.
[12] S. Rawal and T. J. Kshirsagar, Numerical simulation on a pump operating in a turbine model, in Proceedings of the twenty-third international pump users symposium, India, 2007.
[13] P. Singh, Optimization of internal hydraulics and system design for pump as turbine with field implementation and evaluation, PhD Thesis, Germany, 2005.
[2] S. Derakhshan and A. Nourbakhsh, Experimental study of characteristic curves of centrifugal pumps working as turbines in different specific speeds, Experimental thermal and fluid science, vol. 32, pp. 801-806, 2008.
[3] S. V. Jain and R. N. Patel, Investigations on pump running in turbine mode: A review of the state-of-the-art, Renewable and Sustainable Energy Reviews, vol. 30, pp. 850-852, 2013.
[4] S. Derakhshan and A. Nourbakhsh, Experimental study of characteristic curves of centrifugal pumps working as turbines in different specific speeds, Experimental thermal and fluid science, vol. 32, pp. 801-806, 2008.
[5] H. Bing, L. Tan, and L. Lu, Prediction method of impeller performance and analysis of loss mechanism for mixed-flow pump, Science China Technological Sciences, vol. 55, no. 7, pp. 1989-1994, 2012.
[6] F. J. Gülich, Pump hydraulics and physical concepts, in Centrifugal Pumps, Second edition, Springer Heidelberg Dordrecht London New York, ISBN 978-3-642-12823-3, 2010, pp. 100-140.
[7] J. M. Chapallaz, Manual on Pumps Used as Turbines, Germany: Lengericher Handelsdruckerei, Lengerich, ISBN 3-528-02069-5, 1992.
[8] S.-S. Yang, F.-Y. Kong, W.-M. Jiang, and W.-M. Jiang, Effects of impeller trimming influencing pump as turbine, Computers & Fluids, vol. 67, pp. 72-78, 2012.
[9] G. Shi, X. Liu, J. Yang, S. Miao, and J. Li, Theoretical research of hydraulic turbine performance based on slip factor within centripetal impeller, Advances in Mechanical Engineering, pp. 1-12, 2015.
[10] B. Djebedjian, Theoretical model to predict the performance of centrifugal pump equipped with splitter blades, MEJ, vol. 34, no. 2, pp. 50-70, 2009.
[11] I. Pădurean, Study of hydraulic losses in the francis turbines, The 6th international conference on hydraulic machinery and hydrodynamics, Timișoara, 2004.
[12] S. Rawal and T. J. Kshirsagar, Numerical simulation on a pump operating in a turbine model, in Proceedings of the twenty-third international pump users symposium, India, 2007.
[13] P. Singh, Optimization of internal hydraulics and system design for pump as turbine with field implementation and evaluation, PhD Thesis, Germany, 2005.