Modification of pump as turbine as a soft pressure reduction systems (SPRS) for utilization in municipal water network

Document Type : Research Paper


Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran


Pressure Reducing Valves (PRV) are being used for decreasing the existing extra pressure in the water distribution network. however, they dissipate a considerable amount of energy. Therefore, the idea of application of Soft Pressure Reducing Systems (SPRS) is proposed, where a PRV is replaced by a hydropower station. The heart of An SPRS is the turbo-generator. One of the advantages of this type of hydropower plants is the opportunity of application of reverse pumps as the turbine. The performance of PATs is very susceptible to the flow amount and geometrical parameters. Therefore, the performance optimization of PATs is essential. In this research study, the performance of a PAT is investigated using computational fluid dynamics and four geometrical modifications are applied in order to improve its performance. The investigated geometrical parameters are volute type and diameter, beveling the impeller blade tip, deviation of the blade inlet angle. Results indicated that the utilization of radial volutes would be suitable when the flow is less than its BEP value most of the time and tangential volutes are suitable for the opposite situation. Decreasing the diameter would increase both the produced power and the efficiency but its influence is more significant for flows less than BEP. moreover, the results indicate that at a forward deviation equal to 5 degrees, the optimum performance of the turbine will be achieved.


[1] Ghaebi H., Bahadorinejad M., Saidi M.H., Energy Efficiency in a Building Complex through Seasonal Storage of Thermal Energy in a Confined Aquifer,The Journal of Energy Equipment and Systems, 5(4): 341-348(2017).
[2] Shahgholian  G., Analysis and Simulation of Dynamic Performance for DFIG-Based Wind Farm Connected to a Distribution System. The Journal of Energy Equipment and Systems 6(2):117-130(2018).
[3] Derakhshan S., Moghimi M., Motawej H., Development of a Mathematical Model to Design an Offshore Wind and Wave Hybrid Energy System. The Journal of Energy Equipment and Systems 6(2):181-200 (2018).
[4] Ødegård H.L., Eidsvik J. & Fleten S,E., Value of Information Analysis of Snow Measurements for the Scheduling of Hydropower Production. The Journal of Energy Systems (2017).
[5] Aasgård, E.K., Naversen, C.Ø., Fodstad, M. et al. : Optimizing day-ahead bid curves in hydropower production. The Journal of Energy Systems (2017).
[6] Alais J.C., Carpentier P., De Lara M., Multi-Usage Hydropower Single Dam Management: Chance-Constrained Optimization and Stochastic Viability. The Journal of Energy Systems (2017) 8: 7.
[7] Weidong S., Ling Z., Weigang Bing L., Tao P. L., Numerical Prediction and Performance Experimental in a Deep-well Centrifugal Pump with Different Impeller Outlet Width. Chinese Journal of Mechanical Engineering, 26:46-52 (2013).
[8] Yi T., Shouqi Y., Jianrui L., Fan Z., Jianping T., Influence of Blade Thickness on Transient Flow Characteristics of Centrifugal Slurry Pump with Semi-open Impeller, Chinese Journal of Mechanical Engineering, 29: 1209-1217 (2016).
[9] Yuilang Z., Yi L., Baoling C., Zuchao Z., Huashu D., Numerical Simulation and Analysis of Solid-liquid Two-phase Flow in Centrifugal Pump, Chinese Journal of Mechanical Engineering, 26:53-60 (2013).
[10] Chapallaz J.M., Eichenberger P., Fischer G., Manual on Pumps used as Turbines, Vieweg Braunschweig, Germany (1992).
[11] Singh P., Optimization of the Internal Hydraulic and of System Design in umps as Turbines with Field Implementation and Evaluation, Ph.D. thesis, University of Karlsruhe, Karlsruhe (2005).
[12] Derakhshan S., Nourbakhsh A., Theoretical, Numerical and Experimental Investigation of Centrifugal Pumps in Reverse Operation, Experimental Thermal and Fluid Science, 32, 1620-1627 (2008).
[13] Derakhshan S., Nourbakhsh A., Mohammadi B., Efficiency Improvement of Centrifugal Reverse Pumps, Journal of Fluids Engineering, 131:1620-1627 (2009). doi:10.1115/1.3059700.
[14] Singh P., Nestmann F., Experimental Optimization of a Free Vortex Propeller Runner for Microhydro Application, Experimental Thermal and Fluid Science, 33:991-1002 (2009).
[15] Yang S., Kong F., Chen B., Research on Pump Volute Design Method Using CFD, International Journal of Rotating Machinery, 124 (2011).
[16] Nautiyal H., Varun Kumar A., Yadav S., Experimental Investigation of Centrifugal Pump Working as Turbine for Small Hydropower Systems, Energy Science and technology, 1:79-86 (2011).doi:10.1088/1755-1315/16/1/012064.
[17] Fecarotta O., Carravetta A., Ramos H. M., CFD and Comparisons for a Pump as Turbine Mesh Reliability and Performance Concerns, International Journal of Energy and Environment, 2:39-48 (2011).
[18] Dribssa E., Nigussie T., Tsegaye B., Performance Analysis of Centrifugal Pump Operating as Turbine for Identified Micro/Pico Hydro Site of Ethiopia, International Journal of Engineering Research and general Science, 3:6-19 (2015).
[19] Guang Li,  W., Effects of Viscosity on Turbine Mode Performance and Flow of a Low Specific Speed Centrifugal Pump, Applied Mathematical Modelling, 40, 904-926 (2016).
[20] Jafarzadeh B., Hajari A. , Alishahi M.M., Akbari M.H., The Flow Simulation of a Low Specific Speed High Speed Centrifugal Pump, Forschung Imingenieurwesen, 74:123-133 (2010).
[21] Guo P., Luo X., Lu J. , Zheng X., Numerical Investigation on Impeller-Volute Interaction in the Centrifugal Pump with Radial GAP and Tongue Profile Variation, In Fluid Machinery and Fluid Mechanics, Beijing, China (2009).
[22] Zhou P.J. , Wang F.J. , Yang M., Internal Flow Numerical Simulation of Double-Suction Centrifugal Pump Using DES Model, IOP Conference Series: Earth and Environmental Science, Beijing, China (2012).
[23] Rodrigues A., Williams A.A., Singh P., Nestmann F., LAI E., Hydraulic Analysis of a Pump as Turbine with CFD and Experimental Data, IMechE seminar, Computational Fluid Dynamics for Fluid Machinery, London, UK (2003).