Research Article
Numerical Simulation and Computational Flow Characterization
Analyses of Centrifugal Pump Operating as Turbine
Du Jianguo,
1
Guanghui Chang,
1
Daniel Adu ,
1,2
Ransford Darko,
3
Muhammad A. S. Khan,
1
and Eric O. Antwi
4
1
School of Management Science & Eng., Jiangsu University, Zhenjiang 212013, China
2
Faculty of Engineering, Accra Technical University, Barnes Road, Accra, Ghana
3
Department of Agricultural Engineering, University of Cape Coast PMB 233, Cape Coast, Ghana
4
Department of Energy and Environmental Engineering, University of Energy and Natural Resources Sunyani, Sunyani, Ghana
Correspondence should be addressed to Daniel Adu; adudaniel39@yahoo.com
Received 29 April 2021; Revised 14 July 2021; Accepted 13 August 2021; Published 21 August 2021
Academic Editor: Xiaoqing Bai
Copyright © 2021 Du Jianguo et al. is is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Using a pump in reverse mode as a hydraulic turbine remains an alternative for hydropower generation in meeting energy needs,
especially for the provision of electricity to remote and rural settlements. e primary challenge with small hydroelectric systems is
attributed to the high price of smaller size hydraulic turbines. A specific commercial pump model, with a flow rate of 12.5 m
3
/h,
head 32 m, pressure side diameter of 50 mm, impeller out, and inlet diameters of 160 mm and 6 mm, respectively, was chosen for
this research. is research aimed to investigate a pump’s flow characteristics as a turbine to help select a suitable pump to be used
as a turbine for micro- or small hydropower construction. Numerical methodologies have been adopted to contribute to the
thoughtful knowledge of pressure and velocity distribution in the pump turbine performance. In this study, the unsteady flow
relations amongst the rotating impeller and stationary volute of the centrifugal pump made up four blades and four splitters.
Intermittent simulation results of pressure and velocity flow characteristics were studied considering diverse impeller suction
angles. e study was conducted by considering a wide range of rotational speeds starting from 750 rpm to 3250 rpm. From the
results, it was found that PAT operation was improved when operated at low speeds compared to high-speed operation. us,
speeds between 1500 rpm and 2000 rpm were suitable for PAT performance. is research helps to realize the unsteady flow
physiognomies, which provide information for future research on PAT. is study makes useful facts available which could be
helpful for the pump turbine development. Future studies should focus on cost analysis and emission generation in
energy generation.
1. Introduction
Centrifugal pumps are commonly used for domestic and
industrial applications such as water supply, energy gen-
eration, flood control, irrigation for agricultural purposes,
and transportation of liquid-solid mixtures. Designs of
hydropower plants are based on its ability to function at all-
out efficiency matching with acceptable speed. Hydroturbine
performance rests on its speed; therefore, it is manufactured
to function at the greatest attainable efficiency in a specific
rapidity. e role head is to provide speed since the speed
rests on its head. e ability of the head variation can affect
the performance of the turbine. erefore, it is essential for
the adjustment of rotational speed to result in a possible all-
out efficiency [1, 2]. PAT A can, in general, take care of
higher flow rates, which sequentially could implicate higher
output energy ranges [3]. Nevertheless, since pump pro-
ducers have not made available pump performance curves in
turbine mode, it is usually not easy to select an appropriate
pump turbine to run suitably at specific operating condi-
tions, which has become a significant challenge [4]. Several
investigational and theoretical research studies were carried
out on the performance of pumps running in reverse [5]. e
easiest way is the pump model-based prediction since the
Hindawi
Complexity
Volume 2021, Article ID 9695452, 9 pages
https://doi.org/10.1155/2021/9695452